This study identified 9 independent predictors of low cardiac output syndrome after coronary artery bypass surgery:
1) Left ventricular ejection fraction less than 20%
2) Repeat operation
3) Emergency operation
4) Female gender
5) Diabetes
6) Age older than 70 years
7) Left main coronary artery stenosis
8) Recent myocardial infarction
9) Triple-vessel disease
The overall prevalence of low cardiac output syndrome was 9.1% and the operative mortality rate was higher for patients who developed it compared to those who did not.
This document discusses the management of hypertrophic cardiomyopathy (HCM). It covers the natural history of HCM, risk stratification including the role of implantable cardioverter defibrillators, pharmacological treatments, and invasive treatments such as alcohol septal ablation and surgical myectomy. Key points discussed include the use of beta blockers as first-line pharmacological therapy, guidelines for ICD implantation, the technique and outcomes of alcohol septal ablation versus surgical myectomy, and recommendations for experienced centers to perform these invasive procedures.
- Implantable cardioverter defibrillators (ICDs) are recommended for patients with hypertrophic cardiomyopathy (HCM) who have survived sudden cardiac arrest, have spontaneous sustained ventricular tachycardia, or meet certain high-risk criteria.
- Risk stratification should be performed at initial evaluation and periodically to determine ICD need based on factors like family history of sudden cardiac death and abnormal blood pressure response.
- For left ventricular outflow tract obstruction, beta blockers and calcium channel blockers are first-line medical therapies while septal myectomy or alcohol septal ablation are invasive options that provide long-term reduction in outflow gradient.
This document reviews the management of hypertensive emergencies associated with aortic dissection and thoracic aortic aneurysms. It discusses that immediate control of blood pressure is critical for these conditions to prevent further damage. For aortic dissections, surgery is usually recommended for Type A dissections while medical therapy is preferred for Type B dissections. The goals of treatment are to relieve symptoms, reduce complications, and prevent rupture. Several antihypertensive drugs are discussed for rapidly lowering blood pressure in hypertensive emergencies associated with these aortic conditions. Outcomes have improved but morbidity and mortality remain high, posing a significant treatment challenge.
This article summarizes the results of a study on 53 patients who underwent alcohol septal ablation for hypertrophic obstructive cardiomyopathy over 8 years of follow up. Significant reductions in left ventricular outflow tract gradients and septal thickness were observed at 6 months follow up. Symptoms improved in the majority of patients. Ten percent of patients required pacemaker implantation. There was 92% survival rate at 8 years. The study demonstrates that alcohol septal ablation is an effective and safe nonsurgical option for treating hypertrophic obstructive cardiomyopathy that provides long-term relief of symptoms.
This document discusses fractional flow reserve (FFR), a technique used during coronary catheterization to measure pressure differences across a coronary stenosis and determine if it is causing myocardial ischemia. An FFR value below 0.75 is considered functionally significant while a value above 0.80 rules out ischemia. FFR is useful for evaluating single-vessel disease, left main stenosis, tandem lesions, diffuse disease, grafts, and ostial lesions. Limitations include inability to assess plaque morphology.
This document discusses the management of hypertrophic cardiomyopathy (HCM). It covers the natural history of HCM, risk stratification including the role of implantable cardioverter defibrillators, pharmacological treatments, and invasive treatments such as alcohol septal ablation and surgical myectomy. Key points discussed include the use of beta blockers as first-line pharmacological therapy, guidelines for ICD implantation, the technique and outcomes of alcohol septal ablation versus surgical myectomy, and recommendations for experienced centers to perform these invasive procedures.
- Implantable cardioverter defibrillators (ICDs) are recommended for patients with hypertrophic cardiomyopathy (HCM) who have survived sudden cardiac arrest, have spontaneous sustained ventricular tachycardia, or meet certain high-risk criteria.
- Risk stratification should be performed at initial evaluation and periodically to determine ICD need based on factors like family history of sudden cardiac death and abnormal blood pressure response.
- For left ventricular outflow tract obstruction, beta blockers and calcium channel blockers are first-line medical therapies while septal myectomy or alcohol septal ablation are invasive options that provide long-term reduction in outflow gradient.
This document reviews the management of hypertensive emergencies associated with aortic dissection and thoracic aortic aneurysms. It discusses that immediate control of blood pressure is critical for these conditions to prevent further damage. For aortic dissections, surgery is usually recommended for Type A dissections while medical therapy is preferred for Type B dissections. The goals of treatment are to relieve symptoms, reduce complications, and prevent rupture. Several antihypertensive drugs are discussed for rapidly lowering blood pressure in hypertensive emergencies associated with these aortic conditions. Outcomes have improved but morbidity and mortality remain high, posing a significant treatment challenge.
This article summarizes the results of a study on 53 patients who underwent alcohol septal ablation for hypertrophic obstructive cardiomyopathy over 8 years of follow up. Significant reductions in left ventricular outflow tract gradients and septal thickness were observed at 6 months follow up. Symptoms improved in the majority of patients. Ten percent of patients required pacemaker implantation. There was 92% survival rate at 8 years. The study demonstrates that alcohol septal ablation is an effective and safe nonsurgical option for treating hypertrophic obstructive cardiomyopathy that provides long-term relief of symptoms.
This document discusses fractional flow reserve (FFR), a technique used during coronary catheterization to measure pressure differences across a coronary stenosis and determine if it is causing myocardial ischemia. An FFR value below 0.75 is considered functionally significant while a value above 0.80 rules out ischemia. FFR is useful for evaluating single-vessel disease, left main stenosis, tandem lesions, diffuse disease, grafts, and ostial lesions. Limitations include inability to assess plaque morphology.
Non cardiac surgery in cardiac patients moTamer Taha
This document discusses guidelines for evaluating and managing cardiac risk in patients undergoing non-cardiac surgery. It outlines factors that increase surgical risk like prolonged stress and changes in thrombotic factors. Complication rates are reported to be 7-11% with 0.8-1.5% mortality depending on precautions. Up to 42% of complications are cardiac related. It provides recommendations on pre-operative testing and risk stratification using indices. Risk reduction strategies discussed include use of beta-blockers, statins, and revascularization. Perioperative management of antiplatelets and anticoagulants is also covered.
This document provides an overview of mechanical circulatory support devices. It discusses the evolution of such devices and their terminology. Temporary devices discussed include intra-aortic balloon pumps and Impella pumps. Long-term devices discussed include pulsatile flow devices like HeartMate I as well as continuous flow devices like HeartMate II, HeartWare HVAD, and HeartMate 3. Clinical trials are summarized that evaluated these devices as bridges to transplant or destination therapy. Biventricular support devices like the total artificial heart are also covered. The document concludes with recommendations from organizations on the use of these devices.
This 12-year retrospective study from a single center evaluated the efficacy and safety of octreotide for the treatment of post-cardiac surgery chylothorax in children. The study found that octreotide resulted in complete resolution of chylothorax in 62% of patients and partial resolution in 34% of patients. Adverse effects were minor and transient. The authors concluded that octreotide is a promising therapeutic option for post-cardiac surgery chylothorax in children based on its efficacy and safety profile.
2017 ESC guidelines for the management of acuteIqbal Dar
The document summarizes key messages from the 2017 ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation. It discusses 14 main points, including the epidemiology of STEMI, the importance of equal treatment for women and men, ECG diagnosis criteria, reperfusion strategy selection, the role of cardiac networks and protocols, antithrombotic therapy, imaging, special patient subsets, and quality indicators for auditing and improving STEMI care. The guidelines emphasize timely reperfusion therapy, coordination across emergency services and hospitals, and evidence-based treatments tailored to individual patient characteristics and circumstances.
This document discusses coronary artery perforation during percutaneous coronary intervention (PCI). Some key points:
- Coronary perforation can occur during or after PCI and is defined as extravasation of contrast or blood from the coronary artery. Proximal or mid vessel perforations are more severe while distal perforations often have a benign course.
- Perforations are classified based on their severity. Treatment depends on the severity and location of the perforation. Conservative measures often suffice for minor perforations while techniques like prolonged balloon inflation or stenting may be needed for more severe perforations to stop bleeding.
- Factors like the use of atherectomy or laser devices, complex lesions, small vessels, and guide
This study compared measurements of cardiac index and stroke volume obtained from impedance cardiography (ICG) to those obtained from thermodilution pulmonary artery catheterization (TD PAC) in 20 post-operative cardiac surgery patients over 8 hours. The correlation between ICG and TD PAC was significant for cardiac index but not stroke volume. When adjusted for fluid balance, the correlation was only significant for patients receiving small volumes of fluid. The study concludes ICG is unlikely to be valuable for hemodynamic monitoring in this patient population.
No-reflow occurs when there is a lack of reperfusion to the myocardium after successful coronary recanalization and is defined as inadequate perfusion without angiographic evidence of vessel obstruction. It occurs in 0.6-3.2% of PCI cases and is associated with increased risk of LV dysfunction, remodeling, arrhythmias, heart failure and cardiac rupture. Diagnosis is typically done using myocardial contrast echocardiography or cardiac MRI. Treatment focuses on improving perfusion and includes vasodilators like adenosine, antithrombotics, mechanical strategies like thrombectomy, and preventing no-reflow through measures like pre-conditioning.
Application of MCS for the Treatment of Advanced Heart Failurefaminteractive
This document contains the slides from a presentation on Mechanical Circulatory Support (MCS) for advanced heart failure. It discusses the growing problem of heart failure, current treatment options and their limitations, and the role that MCS can play through strategies like Bridge to Transplant and Destination Therapy. It highlights improvements in continuous-flow LVADs like the HeartMate II that have increased survival for bridge to transplant patients. However, it notes that heart transplantation will never meet demand due to limited organ availability, and MCS provides an important alternative for patients who are not transplant candidates.
Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/ARVC) is a genetic heart condition characterized by structural abnormalities and fatty infiltration of the right ventricle, leading to ventricular arrhythmias and sudden cardiac death. It is a common cause of sudden cardiac death in young athletes. Clinical features include palpitations, syncope, chest pain, and dyspnea. Diagnosis relies on a combination of ECG findings, echocardiogram abnormalities of the right ventricle, and genetic testing.
No reflow Phenomenon Dr Hafeesh Fazulu - Pushpagiri - Jan 2021Hafeesh Fazulu
No-reflow phenomenon refers to the inability to perfuse the myocardium after opening a previously occluded coronary artery. It results from endothelial damage, platelet and fibrin embolization, vasospasm, and tissue edema overwhelming the coronary microcirculation. Risk factors include thrombus presence, cardiogenic shock, increased reperfusion time, and hyperglycemia. Diagnosis involves contrast staining in the coronary artery and residual chest pain after angioplasty. Treatment aims to prevent no-reflow through optimal blood sugar control, statin use, anticoagulation, and intracoronary nitrates. Pharmacological therapies like adenosine, statins, and calcium inhibitors may also help. Measurement of treatment outcome can be
No reflow and slow flow phenomenon during pcirahul arora
This document discusses strategies and prevention of slow flow and no-reflow phenomenon during percutaneous coronary intervention (PCI). It defines no-reflow as inadequate myocardial perfusion through a coronary artery without mechanical obstruction. No-reflow occurs in 8-11% of primary PCIs and is associated with worse clinical outcomes. The pathophysiology involves distal embolization, ischemic injury, reperfusion injury, and individual patient susceptibility. Preventing no-reflow requires reducing thrombus burden, ischemia time, reperfusion injury through anti-inflammatory drugs, and addressing risk factors like diabetes.
Important Clinical Trials In Cardiology - An Overview 2016-17Amit Verma
A randomized clinical trial compared outcomes of 885 patients with STEMI and multivessel disease who underwent primary PCI of an infarct artery and were then randomly assigned to either complete revascularization of additional arteries guided by FFR (fractional flow reserve) or no further intervention. The primary composite outcome of death, MI, revascularization or stroke occurred in 8% of those who received complete revascularization versus 21% of those who received PCI only of the infarct artery. Complete revascularization significantly reduced risk of future cardiovascular events.
Perioperative myocardial infarction is a common cause of morbidity and mortality in patients undergoing noncardiac surgery. It can occur through acute coronary syndrome or prolonged myocardial ischemia in patients with stable coronary artery disease. Diagnosis is difficult as symptoms often do not present in anesthetized patients. Risk is determined by patient clinical factors, exercise capacity, and surgery risk. Management may include beta blockers, statins, aspirin, and evaluating need for revascularization based on standard criteria.
Rate vs rhythm control, what is new in esc 2020salah_atta
The document discusses rate and rhythm control strategies for atrial fibrillation (AF) management. It recommends that a target heart rate of under 80 beats per minute at rest and under 110 beats per minute is sufficient for rate control of AF. While some antiarrhythmic drugs can help with rate control, amiodarone should generally only be used for rhythm control. Catheter ablation and pacemakers are options for non-pharmacological rate control. The document also discusses catheter ablation as a first-line therapy for AF according to recent clinical trials, and lifestyle modifications that can help reduce AF recurrence after ablation.
Austin Spine is an open access, peer reviewed, scholarly journal dedicated to publish articles covering all areas of Spine.
The journal aims to promote latest information and provide a forum for doctors, researchers, physicians, and healthcare professionals to find most recent advances in the areas of Spine. Austin Spine accepts research articles, reviews, mini reviews, case reports and rapid communication covering all aspects of Spine.
Austin Spine strongly supports the scientific up gradation and fortification in related scientific research community by enhancing access to peer reviewed scientific literary works. Austin Publishing Group also brings universally peer reviewed journals under one roof thereby promoting knowledge sharing.
This document discusses the no-reflow phenomenon, which occurs when restoration of coronary artery patency after procedures like primary percutaneous coronary intervention (PCI) does not translate to improved tissue perfusion. No-reflow occurs in 30% of patients after reperfusion for acute myocardial infarction and is associated with worse outcomes. It is caused by microvascular obstruction from distal embolization, ischemic injury, reperfusion injury, and individual patient susceptibility. Methods to diagnose no-reflow include angiography, coronary Doppler, cardiac MRI, and myocardial contrast echocardiography. Prevention strategies target reducing ischemic time, microvascular spasm, and distal embolization through early reperfusion, pharmacological agents, and ischemic conditioning techniques.
Aortic Dissection with Hemopericardium and Thrombosed Left Common Iliac Arter...Vinod Namana
#aortic dissection #tamponade #hemopericardium #pericardial effusion #leg ischemia #type a dissection #shock #cardiogenic shock.
An aortic dissection is an uncommon serious condition, which usually presents with chest pain or upper back pain. Symptoms of aortic dissection may mimic those of other diseases, often leading to delay in diagnosis. We report an unusual case of aortic dissection with hemopericardium and thrombosed left common iliac artery presenting as acute limb ischemia. Maintaining a high index of clinical suspicion for aortic pathology could possibly lead to identification and timely management of a greater number of patients who have atypical presentations. This would be especially true for patients who have catastrophic presentations with unexplained symptoms.
This document provides an overview of vascular laboratory assessments for peripheral arterial disease (PAD). It discusses the importance of noninvasive tests like ankle-brachial pressure index (ABPI) in evaluating PAD and outlines the history, indications, modalities, and clinical applications of various physiologic tests. These include segmental limb pressure monitoring, exercise testing, reactive hyperemia testing, toe-brachial indexing, and plethysmography for evaluating the severity and location of PAD.
The ENVISAGE-TAVI trial compared edoxaban to warfarin for stroke prevention in patients with atrial fibrillation following transcatheter aortic valve replacement (TAVR). The trial randomized 1426 patients 1:1 to edoxaban 60 mg daily or dose-adjusted warfarin. The primary endpoint was a composite of death, myocardial infarction, ischemic stroke, systemic embolism, valve thrombosis or major bleeding (net adverse clinical events). Edoxaban was found to be noninferior to warfarin for the primary endpoint with a hazard ratio of 0.82 (95% CI 0.65-1.04). Rates of major bleeding were also similar between the groups. The
Background: Myocarditis is a relatively common inflammatory disease that affects the myocardium. Infectious disease accounts for most of the cases either because of a direct viral infection or post-viral immune-mediated reaction. Cardiovascular magnetic resonance (CMR) has become an established non-invasive diagnosis tool for acute myocarditis. A recent large single centre study with patients with biopsy-proven viral myocarditis undergoing CMR scans found a high rate of mortality. The aim of this study was to assess the rate of clinical events in our population of patients with diagnosed myocarditis by CMR scan.
Methods: Patients who consulted to the emergency department with diagnosis of myocarditis by CMR were retrospectively included in the study from January 2008 to May 2012. A CMR protocol was used in all patients, and were followed up to assess the rate of the composite endpoint of all-cause death, congestive heart failure, sudden cardiac death, hospitalization for cardiac cause, recurrent myocarditis or need of radiofrequency ablation or implantable cardiac defibrillator (ICD). A descriptive statistical analysis was performed.
Results: Thirty-two patients with myocarditis were included in the study. The mean age was 42.6±21.2 years and 81.2% were male. In a mean follow up of 30.4±17.8 months, the rate of the composite endpoint of all-cause death, congestive heart failure, sudden cardiac death, hospitalization for cardiac cause, recurrent myocarditis or need of radiofrequency ablation or ICD was 15.6% (n=5). Two patients had heart failure (one of them underwent heart transplant), one patient needed ICD because of ventricular tachycardia and two other patients were re-hospitalized, for recurrent chest pain and for recurrent myocarditis respectively.
Conclusions: In our series of acute myocarditis diagnosed by CMR we found a low rate of cardiovascular events without mortality. These findings might oppose data from recently published myocarditis trials.
Non cardiac surgery in cardiac patients moTamer Taha
This document discusses guidelines for evaluating and managing cardiac risk in patients undergoing non-cardiac surgery. It outlines factors that increase surgical risk like prolonged stress and changes in thrombotic factors. Complication rates are reported to be 7-11% with 0.8-1.5% mortality depending on precautions. Up to 42% of complications are cardiac related. It provides recommendations on pre-operative testing and risk stratification using indices. Risk reduction strategies discussed include use of beta-blockers, statins, and revascularization. Perioperative management of antiplatelets and anticoagulants is also covered.
This document provides an overview of mechanical circulatory support devices. It discusses the evolution of such devices and their terminology. Temporary devices discussed include intra-aortic balloon pumps and Impella pumps. Long-term devices discussed include pulsatile flow devices like HeartMate I as well as continuous flow devices like HeartMate II, HeartWare HVAD, and HeartMate 3. Clinical trials are summarized that evaluated these devices as bridges to transplant or destination therapy. Biventricular support devices like the total artificial heart are also covered. The document concludes with recommendations from organizations on the use of these devices.
This 12-year retrospective study from a single center evaluated the efficacy and safety of octreotide for the treatment of post-cardiac surgery chylothorax in children. The study found that octreotide resulted in complete resolution of chylothorax in 62% of patients and partial resolution in 34% of patients. Adverse effects were minor and transient. The authors concluded that octreotide is a promising therapeutic option for post-cardiac surgery chylothorax in children based on its efficacy and safety profile.
2017 ESC guidelines for the management of acuteIqbal Dar
The document summarizes key messages from the 2017 ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation. It discusses 14 main points, including the epidemiology of STEMI, the importance of equal treatment for women and men, ECG diagnosis criteria, reperfusion strategy selection, the role of cardiac networks and protocols, antithrombotic therapy, imaging, special patient subsets, and quality indicators for auditing and improving STEMI care. The guidelines emphasize timely reperfusion therapy, coordination across emergency services and hospitals, and evidence-based treatments tailored to individual patient characteristics and circumstances.
This document discusses coronary artery perforation during percutaneous coronary intervention (PCI). Some key points:
- Coronary perforation can occur during or after PCI and is defined as extravasation of contrast or blood from the coronary artery. Proximal or mid vessel perforations are more severe while distal perforations often have a benign course.
- Perforations are classified based on their severity. Treatment depends on the severity and location of the perforation. Conservative measures often suffice for minor perforations while techniques like prolonged balloon inflation or stenting may be needed for more severe perforations to stop bleeding.
- Factors like the use of atherectomy or laser devices, complex lesions, small vessels, and guide
This study compared measurements of cardiac index and stroke volume obtained from impedance cardiography (ICG) to those obtained from thermodilution pulmonary artery catheterization (TD PAC) in 20 post-operative cardiac surgery patients over 8 hours. The correlation between ICG and TD PAC was significant for cardiac index but not stroke volume. When adjusted for fluid balance, the correlation was only significant for patients receiving small volumes of fluid. The study concludes ICG is unlikely to be valuable for hemodynamic monitoring in this patient population.
No-reflow occurs when there is a lack of reperfusion to the myocardium after successful coronary recanalization and is defined as inadequate perfusion without angiographic evidence of vessel obstruction. It occurs in 0.6-3.2% of PCI cases and is associated with increased risk of LV dysfunction, remodeling, arrhythmias, heart failure and cardiac rupture. Diagnosis is typically done using myocardial contrast echocardiography or cardiac MRI. Treatment focuses on improving perfusion and includes vasodilators like adenosine, antithrombotics, mechanical strategies like thrombectomy, and preventing no-reflow through measures like pre-conditioning.
Application of MCS for the Treatment of Advanced Heart Failurefaminteractive
This document contains the slides from a presentation on Mechanical Circulatory Support (MCS) for advanced heart failure. It discusses the growing problem of heart failure, current treatment options and their limitations, and the role that MCS can play through strategies like Bridge to Transplant and Destination Therapy. It highlights improvements in continuous-flow LVADs like the HeartMate II that have increased survival for bridge to transplant patients. However, it notes that heart transplantation will never meet demand due to limited organ availability, and MCS provides an important alternative for patients who are not transplant candidates.
Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/ARVC) is a genetic heart condition characterized by structural abnormalities and fatty infiltration of the right ventricle, leading to ventricular arrhythmias and sudden cardiac death. It is a common cause of sudden cardiac death in young athletes. Clinical features include palpitations, syncope, chest pain, and dyspnea. Diagnosis relies on a combination of ECG findings, echocardiogram abnormalities of the right ventricle, and genetic testing.
No reflow Phenomenon Dr Hafeesh Fazulu - Pushpagiri - Jan 2021Hafeesh Fazulu
No-reflow phenomenon refers to the inability to perfuse the myocardium after opening a previously occluded coronary artery. It results from endothelial damage, platelet and fibrin embolization, vasospasm, and tissue edema overwhelming the coronary microcirculation. Risk factors include thrombus presence, cardiogenic shock, increased reperfusion time, and hyperglycemia. Diagnosis involves contrast staining in the coronary artery and residual chest pain after angioplasty. Treatment aims to prevent no-reflow through optimal blood sugar control, statin use, anticoagulation, and intracoronary nitrates. Pharmacological therapies like adenosine, statins, and calcium inhibitors may also help. Measurement of treatment outcome can be
No reflow and slow flow phenomenon during pcirahul arora
This document discusses strategies and prevention of slow flow and no-reflow phenomenon during percutaneous coronary intervention (PCI). It defines no-reflow as inadequate myocardial perfusion through a coronary artery without mechanical obstruction. No-reflow occurs in 8-11% of primary PCIs and is associated with worse clinical outcomes. The pathophysiology involves distal embolization, ischemic injury, reperfusion injury, and individual patient susceptibility. Preventing no-reflow requires reducing thrombus burden, ischemia time, reperfusion injury through anti-inflammatory drugs, and addressing risk factors like diabetes.
Important Clinical Trials In Cardiology - An Overview 2016-17Amit Verma
A randomized clinical trial compared outcomes of 885 patients with STEMI and multivessel disease who underwent primary PCI of an infarct artery and were then randomly assigned to either complete revascularization of additional arteries guided by FFR (fractional flow reserve) or no further intervention. The primary composite outcome of death, MI, revascularization or stroke occurred in 8% of those who received complete revascularization versus 21% of those who received PCI only of the infarct artery. Complete revascularization significantly reduced risk of future cardiovascular events.
Perioperative myocardial infarction is a common cause of morbidity and mortality in patients undergoing noncardiac surgery. It can occur through acute coronary syndrome or prolonged myocardial ischemia in patients with stable coronary artery disease. Diagnosis is difficult as symptoms often do not present in anesthetized patients. Risk is determined by patient clinical factors, exercise capacity, and surgery risk. Management may include beta blockers, statins, aspirin, and evaluating need for revascularization based on standard criteria.
Rate vs rhythm control, what is new in esc 2020salah_atta
The document discusses rate and rhythm control strategies for atrial fibrillation (AF) management. It recommends that a target heart rate of under 80 beats per minute at rest and under 110 beats per minute is sufficient for rate control of AF. While some antiarrhythmic drugs can help with rate control, amiodarone should generally only be used for rhythm control. Catheter ablation and pacemakers are options for non-pharmacological rate control. The document also discusses catheter ablation as a first-line therapy for AF according to recent clinical trials, and lifestyle modifications that can help reduce AF recurrence after ablation.
Austin Spine is an open access, peer reviewed, scholarly journal dedicated to publish articles covering all areas of Spine.
The journal aims to promote latest information and provide a forum for doctors, researchers, physicians, and healthcare professionals to find most recent advances in the areas of Spine. Austin Spine accepts research articles, reviews, mini reviews, case reports and rapid communication covering all aspects of Spine.
Austin Spine strongly supports the scientific up gradation and fortification in related scientific research community by enhancing access to peer reviewed scientific literary works. Austin Publishing Group also brings universally peer reviewed journals under one roof thereby promoting knowledge sharing.
This document discusses the no-reflow phenomenon, which occurs when restoration of coronary artery patency after procedures like primary percutaneous coronary intervention (PCI) does not translate to improved tissue perfusion. No-reflow occurs in 30% of patients after reperfusion for acute myocardial infarction and is associated with worse outcomes. It is caused by microvascular obstruction from distal embolization, ischemic injury, reperfusion injury, and individual patient susceptibility. Methods to diagnose no-reflow include angiography, coronary Doppler, cardiac MRI, and myocardial contrast echocardiography. Prevention strategies target reducing ischemic time, microvascular spasm, and distal embolization through early reperfusion, pharmacological agents, and ischemic conditioning techniques.
Aortic Dissection with Hemopericardium and Thrombosed Left Common Iliac Arter...Vinod Namana
#aortic dissection #tamponade #hemopericardium #pericardial effusion #leg ischemia #type a dissection #shock #cardiogenic shock.
An aortic dissection is an uncommon serious condition, which usually presents with chest pain or upper back pain. Symptoms of aortic dissection may mimic those of other diseases, often leading to delay in diagnosis. We report an unusual case of aortic dissection with hemopericardium and thrombosed left common iliac artery presenting as acute limb ischemia. Maintaining a high index of clinical suspicion for aortic pathology could possibly lead to identification and timely management of a greater number of patients who have atypical presentations. This would be especially true for patients who have catastrophic presentations with unexplained symptoms.
This document provides an overview of vascular laboratory assessments for peripheral arterial disease (PAD). It discusses the importance of noninvasive tests like ankle-brachial pressure index (ABPI) in evaluating PAD and outlines the history, indications, modalities, and clinical applications of various physiologic tests. These include segmental limb pressure monitoring, exercise testing, reactive hyperemia testing, toe-brachial indexing, and plethysmography for evaluating the severity and location of PAD.
The ENVISAGE-TAVI trial compared edoxaban to warfarin for stroke prevention in patients with atrial fibrillation following transcatheter aortic valve replacement (TAVR). The trial randomized 1426 patients 1:1 to edoxaban 60 mg daily or dose-adjusted warfarin. The primary endpoint was a composite of death, myocardial infarction, ischemic stroke, systemic embolism, valve thrombosis or major bleeding (net adverse clinical events). Edoxaban was found to be noninferior to warfarin for the primary endpoint with a hazard ratio of 0.82 (95% CI 0.65-1.04). Rates of major bleeding were also similar between the groups. The
Background: Myocarditis is a relatively common inflammatory disease that affects the myocardium. Infectious disease accounts for most of the cases either because of a direct viral infection or post-viral immune-mediated reaction. Cardiovascular magnetic resonance (CMR) has become an established non-invasive diagnosis tool for acute myocarditis. A recent large single centre study with patients with biopsy-proven viral myocarditis undergoing CMR scans found a high rate of mortality. The aim of this study was to assess the rate of clinical events in our population of patients with diagnosed myocarditis by CMR scan.
Methods: Patients who consulted to the emergency department with diagnosis of myocarditis by CMR were retrospectively included in the study from January 2008 to May 2012. A CMR protocol was used in all patients, and were followed up to assess the rate of the composite endpoint of all-cause death, congestive heart failure, sudden cardiac death, hospitalization for cardiac cause, recurrent myocarditis or need of radiofrequency ablation or implantable cardiac defibrillator (ICD). A descriptive statistical analysis was performed.
Results: Thirty-two patients with myocarditis were included in the study. The mean age was 42.6±21.2 years and 81.2% were male. In a mean follow up of 30.4±17.8 months, the rate of the composite endpoint of all-cause death, congestive heart failure, sudden cardiac death, hospitalization for cardiac cause, recurrent myocarditis or need of radiofrequency ablation or ICD was 15.6% (n=5). Two patients had heart failure (one of them underwent heart transplant), one patient needed ICD because of ventricular tachycardia and two other patients were re-hospitalized, for recurrent chest pain and for recurrent myocarditis respectively.
Conclusions: In our series of acute myocarditis diagnosed by CMR we found a low rate of cardiovascular events without mortality. These findings might oppose data from recently published myocarditis trials.
R. Loch Macdonald, M.D., Ph.D.
Community Neurosciences Institute
Fresno, California, USA
Angiographic vasospasm and more accurately, delayed cerebral ischemia, continue to contribute to morbidity and mortality in patients with aneurysmal subarachnoid hemorrhage (SAH). It is known that angiographic vasospasm is common after SAH, occurring in two-thirds of patients. Cerebral infarctions that developed days after the SAH have been attributed to angiographic vasospasm, occuring in about a third of patients, although this has always been controversial. Angiographic vasospasm theoretically can only damage the brain by restricting blood flow but there is no easy, accurate, widely available method to measure cerebral blood flow and this is not the measurement we need. Blood flow depends on metabolic demand so what we need to know to determine if angiographic vasospasm is causing ischemia is oxygen extraction fraction in the brain tissue supplied the the spastic artery. Without this measurement, the attribution of ischemia to vasospasm is subjective. Since angiographic vasospasm is essentially the only detectable delayed phenomenon after SAH, we focus on it and apply tremendous resources to preventing or reversing the vasospasm. Undoubtedly angiographic vasospasm can cause cerebral infarctions, but it has to be severe and flow limiting. But SAH is a complex disease. There are many other causes for cerebral infarctions after SAH, the most common being due to the aneurysm repair procedure. And a given degree of vasospasm may cause infarction in a volume-depleted patient with poor collateral blood supply but not in a patient without these things. There also are hypodense brain lesions after SAH that are due to intracerebral hemorrhages. There can be hypodensities in the brain directly under usually thick SAH where the brain dies. This observation in particular supports a role for cortical spreading depolarizations/ischemia as a cause of infarction after SAH. Other macromolecular processes that are hypothesized to cause brain damage after SAH include microthromboembolism, changes in the microcirculation, delayed brain cell apoptosis and capillary transit time heterogeneity. Determining the importance of these things is hindered by the lack of an easy way to detect them in patients. It is also known that poor grade patients, who presumably have more early brain injury and ischemia than good grade patients, are more prone to delayed cerebral ischemia, suggesting increased sensitivity to secondary insults of the already injured brain. We also assume delayed neurological deterioration when attributed to vasospasm or delayed cerebral ischemia, is purely due to ischemia. While knowledge about what happens pathophysiologically after SAH is increasing, management of delayed cerebral ischemia still focuses on detecting angiographic vasospasm and then augmenting the blood pressure to improve cerebral blood flow or dilating the spastic arteries with balloons or drugs.
Combined carotid and coronary disease the strategy should beuvcd
1. Combined carotid and coronary artery disease presents challenges in determining the optimal treatment strategy. Performing carotid endarterectomy and coronary artery bypass grafting simultaneously or in stages both carry risks.
2. Factors such as the severity of stenosis in the carotid and coronary arteries, and a patient's surgical risk profile must be considered. High grade stenosis in both territories typically warrants staged procedures to avoid complications.
3. Preventing embolic sources, maintaining adequate cerebral perfusion and temperature, and using monitoring techniques can help reduce risks of central nervous system injuries during combined or staged carotid and cardiac surgeries. Close evaluation of individual patient characteristics is important for surgical planning.
1) The study examined predictors of ischemia and outcomes in 169 Egyptian patients with diabetes referred for nuclear perfusion imaging over 2 years of follow up.
2) Significant relationships were found between higher summed stress scores and outcomes of sudden cardiac death, myocardial infarction, and heart failure. Higher summed rest scores also significantly predicted several adverse outcomes.
3) Degree of typical chest pain, transient left ventricular dilation, lung uptake on imaging, and extent of ischemia (summed difference score) were independent predictors of myocardial infarction. Transient left ventricular dilation was the strongest predictor of sudden cardiac death.
PVCs are common, occurring in 40-75% of the general population on Holter monitoring. While traditionally thought to be benign without structural heart disease, they represent an increased risk of sudden death in patients with conditions like ischemic heart disease. The frequency and complexity of PVCs is associated with increased mortality in these patients. Implantable cardioverter defibrillators are indicated for those with nonsustained ventricular tachycardia due to prior myocardial infarction and left ventricular ejection fraction ≤40% who are inducible for sustained ventricular arrhythmias on electrophysiological study. However, for patients with congestive heart failure, PVCs do not provide significant prognostic value beyond clinical variables. The concept of PVC-induced
Carotid revascularization in cad patientsDIPAK PATADE
Carotid artery disease is common in patients with coronary artery disease undergoing coronary artery bypass grafting (CABG). The incidence of perioperative stroke after CABG is around 1.6-3.1%, with risks increased by factors like aortic atherosclerosis, atrial fibrillation, prior stroke, and carotid stenosis. Strokes are often embolic and occur during or soon after surgery. Asymptomatic carotid stenosis alone may not increase stroke risks significantly, but bilateral or recently symptomatic stenosis does. Careful screening and management of atherosclerotic risk factors can help reduce perioperative stroke risks in patients with coexisting carotid and coronary artery disease.
This study aimed to determine if preoperative hematological parameters and risk factors could predict in-hospital mortality for patients undergoing surgery to repair Type A aortic dissection. The study reviewed data from 78 patients who underwent deep hypothermic circulatory arrest surgery. Only preoperative creatinine levels were higher in patients who died. Total circulatory arrest time and cross-clamp time during surgery were found to be factors affecting mortality, with times over 44.5 minutes and 71 minutes respectively predicting higher risk of death. The study concluded that hematological biomarkers alone may be insufficient for estimating mortality risk, and intraoperative factors like longer circulatory arrest and clamp times impact outcomes for Type A aortic dissection surgery.
This study evaluated the efficacy of intra-arterial nimodipine (IAN) treatment for cerebral vasospasm (CV) in 25 patients at a Danish hospital. IAN resulted in a positive angiographic response in 95.1% of treatment sessions. However, the immediate clinical improvement was only observed in 12% of patients. At discharge and three-month follow-up, 20% had a favorable outcome, 40% had a moderate to poor outcome, and 40% had died. Increased number of affected vessels, number of IAN procedures, and longer delay between symptomatic CV onset and IAN treatment predicted poorer clinical outcomes. While IAN was generally effective at reversing CV angiographically, it did not always translate to clinical
postgraduate education for cardiothoracic anaesthesia and intensive care doctors in cardiac operations on patients with unstable ischemic heart disease
This study evaluated D-dimer levels in 80 patients with chronic atrial fibrillation to determine if D-dimer could diagnose left atrial appendage thrombus. The patients underwent transesophageal echocardiography and were divided into two groups: those with thrombus and those without. All patients in the thrombus group had elevated D-dimer levels, while only 28.5% of patients without thrombus had elevated levels. After 3 months of anticoagulation therapy, D-dimer levels decreased significantly in the thrombus group and thrombus resolved in 77.8% of patients. The study concludes that D-dimer has 100% sensitivity and 71.4% specificity for diagnosing left
How should recently symptomatic patients be treated urgent cea or casuvcd
Recent symptomatic patients with carotid artery stenosis can be treated with either urgent carotid endarterectomy (CEA) or carotid artery stenting (CAS). While early studies found CEA to have better outcomes, more recent trials like CREST showed comparable rates of stroke and death between CEA and CAS. For recently symptomatic patients specifically, CEA may still be preferred to CAS due to concerns about stabilizing carotid plaque after stenting. Operator experience also impacts outcomes, so treatment should be individualized based on each patient's clinical situation.
This study investigated the effects of intracoronary nicorandil and tirofiban on no-reflow phenomenon and clinical outcomes in 438 patients with acute coronary syndrome undergoing percutaneous coronary intervention. Both nicorandil and tirofiban improved TIMI blood flow grades after PCI, with TIMI grade 3 flow in 85.2% and 81.4% of patients respectively. There was no significant difference in major adverse cardiac events between the two groups. The study concluded that intracoronary nicorandil can improve coronary perfusion in ACS patients, but its effect on long-term prognosis requires further research.
DANISH is a major breakthrough trial published in NEJM on 29/09/2016 regarding Defibrillator Implantation in Patients with Nonischemic Systolic Heart Failure. All content of this slide is Copy right of NEJM.
The recalibrated thoracic revised cardiac risk index (ThRCRI) aims to predict cardiac risk for patients undergoing lung resection. This study externally validates the ThRCRI in 2,621 patients who underwent lobectomy or pneumonectomy. Patients were grouped into four risk classes by the ThRCRI. The incidence of major cardiac complications increased from 0.9% in the lowest risk class to 18% in the highest risk class, demonstrating the ThRCRI's ability to stratify risk. Bootstrapping analysis supported the ThRCRI's reliability in predicting cardiac risk across different patient populations. The ThRCRI is a useful tool for identifying patients needing further cardiac testing before lung resection.
The document discusses endovascular treatment of aortic dissection. It begins with an introduction to aortic dissection, including definitions, classifications, epidemiology, clinical presentation, and natural history. It then discusses the diagnosis and imaging of aortic dissection. Medical and surgical management strategies are reviewed. Endovascular techniques for treating various types of aortic dissection are summarized. Key considerations for endovascular stent grafting as an alternative to open surgery are outlined.
Coronary artery perforation complicating percutaneous coronary interventionAbdulsalam Taha
This study summarizes the management of 24 patients who experienced coronary artery perforation as a complication of percutaneous coronary intervention (PCI) at a hospital in Iraq from 2009-2016. The majority of perforations involved the left anterior descending artery and were classified as Type II or III, requiring sealing with covered stents. Thirteen patients also required drainage of pericardial effusions. All perforations were immediately diagnosed and treated, with no patients requiring surgery or experiencing mortality. The low rate of coronary artery perforation complications in this study, primarily managed using covered stents, demonstrates the effectiveness of the approaches used at this hospital.
The introduction of more sensitive cardiac troponin assays and lower diagnostic thresholds led to a revision of guidelines classifying myocardial injury by cause. The third universal definition differentiated between myocardial infarction due to plaque rupture (type 1) and due to ischemia from other illnesses (type 2), and classified injury without ischemia as acute or chronic injury. Both injury and type 2 infarction are common, occurring in over a third of hospitalized patients, who have poor short and long-term outcomes.
This document provides an overview of ST-elevation myocardial infarction (STEMI) including its epidemiology, etiology, pathophysiology, risk factors, diagnosis, and current guideline-directed management. It begins with definitions of STEMI and acute coronary syndrome. Key points include that STEMI accounts for 30-40% of myocardial infarctions in the US with a mortality rate of 8.8-18.4%. Risk factors include age, gender, family history, hypertension, diabetes, hyperlipidemia, and tobacco use. Diagnosis is made through ECG showing ST elevations and elevated cardiac biomarkers. Current treatment involves prompt reperfusion therapy with either primary percutaneous coronary intervention or fibrinolytic therapy to restore blood flow to the
This study optimized prebiotic mixtures in soybean milk using mixture experiments. Thirteen soybean milk formulations with varying proportions of inulin, galacto-oligosaccharides, and isomalto-oligosaccharides were evaluated based on sensory properties and growth of probiotic bacteria. The growth of Bifidobacterium bifidum, Lactobacillus plantarum, and Lactobacillus acidophilus were used to determine the best prebiotic mixture. The optimized formulation containing 0.11 inulin, 0.62 galacto-oligosaccharides, and 0.27 isomalto-oligosaccharides stimulated the highest growth of all three probiotic strains without affecting sensory attributes.
This document summarizes key concepts regarding drug chirality and stereoisomers in anesthesia. It defines terms like enantiomers, stereoisomers, and the R/S naming system. It discusses how stereoisomers can have different receptor affinities and pharmacokinetic profiles. As an example, it examines the local anesthetics bupivacaine, levobupivacaine (S-bupivacaine), and ropivacaine. It describes how these drugs act on sodium channels and reviews clinical studies comparing their sensory/motor blocking effects.
Anesthetic Effects On The Fetus And NewbornAhmed Shalabi
Anesthetics are generally not teratogenic, though some animal studies found increased abnormalities with nitrous oxide exposure. Epidemiological studies in humans found no association between anesthetic exposure and birth defects. While anesthetics are not structural teratogens, some may cause behavioral changes in developing brains by interfering with receptor development. Epidural analgesia is associated with increased maternal fever during labor, which epidemiological evidence links to higher risks of cerebral palsy and other neurological injuries in infants. However, the mechanisms linking epidurals, fever, and injury remain unclear.
Protocol For Endovasc Repair Of Rupture A AAhmed Shalabi
1) The authors established a protocol for endovascular repair of ruptured abdominal aortic aneurysms (r-AAAs) to address limitations in coordinating patient care between the emergency department and operating room.
2) As part of the protocol, 5 patients underwent simulated emergencies to test the protocol, which involved alerting vascular surgery and preparing an endovascular-capable operating room.
3) Since implementing the protocol, 40 of 42 actual r-AAA patients underwent successful endovascular repair, with a mortality rate of 18% once the protocol was established to streamline patient care.
This review article discusses the use of ketamine as an induction agent for rapid sequence induction (RSI) of anesthesia in emergency patients who are hemodynamically compromised. The authors argue that ketamine represents a rational choice for RSI in such patients due to its favorable pharmacological properties that confer hemodynamic stability compared to other induction agents. Specifically, ketamine has a short time to reach effective brain concentrations, does not significantly lower blood pressure, and maintains cerebral perfusion pressure and intracranial pressure within normal limits when used for induction and maintained with general anesthesia. While ketamine has traditionally been contraindicated when brain injury is present, the authors claim any adverse effects on intracranial pressure or cerebral blood flow are mit
perioperative management Pacemaker Insertion In Congenital HeartAhmed Shalabi
This document describes the perioperative management of a 6-month-old boy undergoing permanent pacemaker implantation for congenital complete heart block. Key aspects of management included premedication with atropine and promethazine to prevent vagal stimulation, induction with ketamine to avoid negative chronotropic effects, and maintenance with non-depressant anesthetics like isoflurane. Intraoperative monitoring and defibrillator equipment were readily available due to the risk of arrhythmias. The pacemaker implantation procedure and postoperative course were uncomplicated with this careful anesthetic approach.
Anesthesia For Children With Congenital Heart Disease1Ahmed Shalabi
This document discusses children with congenital heart disease and provides information on:
1. The incidence of congenital heart disease is 7 to 10 per 1000 live births, with certain populations having higher rates.
2. Congenital heart disease can range from simple defects like atrial septal defects to complex conditions like hypoplastic left heart syndrome.
3. Proper preoperative evaluation is important for anesthetic planning and involves understanding the child's specific cardiac anatomy and physiology.
Anesthesia And Congenital Heart DiseaseAhmed Shalabi
This document summarizes adult congenital heart disease and considerations for anesthesia management. It discusses that:
1) Congenital heart diseases are increasingly common as more children with complex defects now survive into adulthood.
2) Adults with CHD can be categorized as those with complete repair, partial/palliative repair, or no operation.
3) Five factors influence perioperative risk - pulmonary hypertension, cyanosis, reoperation, arrhythmias, and ventricular dysfunction.
1) Begin resuscitation immediately for patients with sepsis-induced hypotension or elevated lactate, aiming to achieve specific hemodynamic and perfusion goals within the first 6 hours.
2) Rapidly identify an infection source and implement source control measures like drainage or debridement as soon as resuscitation allows.
3) Administer broad-spectrum antibiotics within 1 hour of recognizing sepsis or septic shock and reassess daily to optimize treatment.
This document provides the table of contents for the book "Perioperative Critical Care Cardiology 2nd edition". The book contains 16 chapters covering topics in perioperative critical care cardiology including sudden death in heart failure, etiology and pathophysiology of heart failure, cardiac protection for noncardiac surgery, hypertensive crises, heart failure and related conditions, circulatory failure monitoring, perioperative risk stratification, hemodynamic monitoring, electrocardiography of heart failure, management of acute heart failure, device therapies, updates on resuscitation, circulatory shock, prevention of cardiac dysfunction associated with surgery, management of hypertension, and advances in dilated cardiomyopathy. The table of contents lists the chapter titles and authors for
Adhd Medication Shortage Uk - trinexpharmacy.comreignlana06
The UK is currently facing a Adhd Medication Shortage Uk, which has left many patients and their families grappling with uncertainty and frustration. ADHD, or Attention Deficit Hyperactivity Disorder, is a chronic condition that requires consistent medication to manage effectively. This shortage has highlighted the critical role these medications play in the daily lives of those affected by ADHD. Contact : +1 (747) 209 – 3649 E-mail : sales@trinexpharmacy.com
Integrating Ayurveda into Parkinson’s Management: A Holistic ApproachAyurveda ForAll
Explore the benefits of combining Ayurveda with conventional Parkinson's treatments. Learn how a holistic approach can manage symptoms, enhance well-being, and balance body energies. Discover the steps to safely integrate Ayurvedic practices into your Parkinson’s care plan, including expert guidance on diet, herbal remedies, and lifestyle modifications.
TEST BANK For Basic and Clinical Pharmacology, 14th Edition by Bertram G. Kat...rightmanforbloodline
TEST BANK For Basic and Clinical Pharmacology, 14th Edition by Bertram G. Katzung, Verified Chapters 1 - 66, Complete Newest Version.
TEST BANK For Basic and Clinical Pharmacology, 14th Edition by Bertram G. Katzung, Verified Chapters 1 - 66, Complete Newest Version.
TEST BANK For Basic and Clinical Pharmacology, 14th Edition by Bertram G. Katzung, Verified Chapters 1 - 66, Complete Newest Version.
TEST BANK For Basic and Clinical Pharmacology, 14th Edition by Bertram G. Katzung, Verified Chapters 1 - 66, Complete Newest Version.
Local Advanced Lung Cancer: Artificial Intelligence, Synergetics, Complex Sys...Oleg Kshivets
Overall life span (LS) was 1671.7±1721.6 days and cumulative 5YS reached 62.4%, 10 years – 50.4%, 20 years – 44.6%. 94 LCP lived more than 5 years without cancer (LS=2958.6±1723.6 days), 22 – more than 10 years (LS=5571±1841.8 days). 67 LCP died because of LC (LS=471.9±344 days). AT significantly improved 5YS (68% vs. 53.7%) (P=0.028 by log-rank test). Cox modeling displayed that 5YS of LCP significantly depended on: N0-N12, T3-4, blood cell circuit, cell ratio factors (ratio between cancer cells-CC and blood cells subpopulations), LC cell dynamics, recalcification time, heparin tolerance, prothrombin index, protein, AT, procedure type (P=0.000-0.031). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and N0-12 (rank=1), thrombocytes/CC (rank=2), segmented neutrophils/CC (3), eosinophils/CC (4), erythrocytes/CC (5), healthy cells/CC (6), lymphocytes/CC (7), stick neutrophils/CC (8), leucocytes/CC (9), monocytes/CC (10). Correct prediction of 5YS was 100% by neural networks computing (error=0.000; area under ROC curve=1.0).
Osteoporosis - Definition , Evaluation and Management .pdfJim Jacob Roy
Osteoporosis is an increasing cause of morbidity among the elderly.
In this document , a brief outline of osteoporosis is given , including the risk factors of osteoporosis fractures , the indications for testing bone mineral density and the management of osteoporosis
These lecture slides, by Dr Sidra Arshad, offer a quick overview of the physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar lead (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
6. Describe the flow of current around the heart during the cardiac cycle
7. Discuss the placement and polarity of the leads of electrocardiograph
8. Describe the normal electrocardiograms recorded from the limb leads and explain the physiological basis of the different records that are obtained
9. Define mean electrical vector (axis) of the heart and give the normal range
10. Define the mean QRS vector
11. Describe the axes of leads (hexagonal reference system)
12. Comprehend the vectorial analysis of the normal ECG
13. Determine the mean electrical axis of the ventricular QRS and appreciate the mean axis deviation
14. Explain the concepts of current of injury, J point, and their significance
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. Chapter 3, Cardiology Explained, https://www.ncbi.nlm.nih.gov/books/NBK2214/
7. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Histololgy of Female Reproductive System.pptxAyeshaZaid1
Dive into an in-depth exploration of the histological structure of female reproductive system with this comprehensive lecture. Presented by Dr. Ayesha Irfan, Assistant Professor of Anatomy, this presentation covers the Gross anatomy and functional histology of the female reproductive organs. Ideal for students, educators, and anyone interested in medical science, this lecture provides clear explanations, detailed diagrams, and valuable insights into female reproductive system. Enhance your knowledge and understanding of this essential aspect of human biology.
Does Over-Masturbation Contribute to Chronic Prostatitis.pptxwalterHu5
In some case, your chronic prostatitis may be related to over-masturbation. Generally, natural medicine Diuretic and Anti-inflammatory Pill can help mee get a cure.
Cell Therapy Expansion and Challenges in Autoimmune DiseaseHealth Advances
There is increasing confidence that cell therapies will soon play a role in the treatment of autoimmune disorders, but the extent of this impact remains to be seen. Early readouts on autologous CAR-Ts in lupus are encouraging, but manufacturing and cost limitations are likely to restrict access to highly refractory patients. Allogeneic CAR-Ts have the potential to broaden access to earlier lines of treatment due to their inherent cost benefits, however they will need to demonstrate comparable or improved efficacy to established modalities.
In addition to infrastructure and capacity constraints, CAR-Ts face a very different risk-benefit dynamic in autoimmune compared to oncology, highlighting the need for tolerable therapies with low adverse event risk. CAR-NK and Treg-based therapies are also being developed in certain autoimmune disorders and may demonstrate favorable safety profiles. Several novel non-cell therapies such as bispecific antibodies, nanobodies, and RNAi drugs, may also offer future alternative competitive solutions with variable value propositions.
Widespread adoption of cell therapies will not only require strong efficacy and safety data, but also adapted pricing and access strategies. At oncology-based price points, CAR-Ts are unlikely to achieve broad market access in autoimmune disorders, with eligible patient populations that are potentially orders of magnitude greater than the number of currently addressable cancer patients. Developers have made strides towards reducing cell therapy COGS while improving manufacturing efficiency, but payors will inevitably restrict access until more sustainable pricing is achieved.
Despite these headwinds, industry leaders and investors remain confident that cell therapies are poised to address significant unmet need in patients suffering from autoimmune disorders. However, the extent of this impact on the treatment landscape remains to be seen, as the industry rapidly approaches an inflection point.
2. The Journal of Thoracic and
Cardiovascular Surgery Rao et al. 39
Volume 112, Number 1
may represent a failure of myocardial protection or Table I. Patient population
difficulty with bypass grafting and is often associated N %
with a higher mortality and prolonged hospital stay. N 4558
A recent randomized clinical trial done at the Sex
University of Toronto by The W a r m H e a r t Investi- Male 3673 81
gators showed no difference in operative mortality Female 885 19
or perioperative myocardial infarction (MI) be- Age (yr) 61.5 _+ 9.6
Timing
tween patients who received w a r m blood or cold Elective 2620 57
blood cardioplegic solution. 2 However, the occurrence Semielective 1130 25
of low cardiac output syndrome was significantly lower Urgent 657 14
in the warm group. Similarly, a large clinical trial that Emergency 151 4
evaluated acadesine as a myocardial protective agent Recent MI 692 15
LVEF
failed to show any difference in the prevalence of >60% 1530 34
perioperative infarction except in a subgroup of pa- 40%-60% 1926 42
tients with high-risk conditions. 3 Because of the low 20%-40% 956 21
rates of operative mortality and perioperative MI, <20% 146 3
studies aimed at developing improved strategies of NYHA class
I 76 2
myocardial protection are unlikely to show a benefit II 654 14
unless they include a large number of patients or limit III 1861 41
their focus to subgroups of patients at high risk. Both IV 1967 43
operative mortality and a new perioperative MI occur CAD
infrequently and these outcome measures are difficult ] vessel 308 7
2 vessel 1083 24
to use in a trial of alternate myocardial protective 3 vessel 3159 69
strategies even in patients at high risk. Left main CAD 808 18
Low cardiac output syndrome is a more frequent Repeat operation 335 7
event and may be modified by improved methods of Diabetes 1086 24
myocardial protection in high-risk subgroups. How- Hypertension 2337 51
PVD 591 13
ever, the syndrome must be carefully defined and its
pathophysiologic components may be better under- LVEF, Left ventricular ejection fraction; NYHA, New York Heart Asso-
ciation; CAD, coronary artery disease; PVD, Peripheral vascular disease.
stood by assessment of the predisposing risk factors.
To make comparisons between studies, the defini-
tion of low cardiac output syndrome must become artery stenoses, the mean arterial pressure was main-
standardized. This study presents the independent tained higher than 70 mm Hg in an attempt to improve
cerebral perfusion. Blood cardioplegic solutions were
preoperative risk factors for the development of low
delivered after oxygenated blood from the bypass circuit
cardiac output syndrome in 4558 consecutive pa- was mixed with a crystalloid solution in a 4:1 ratio. Blood
tients undergoing isolated coronary artery bypass cardioplegic solution was administered either in an ante-
grafting at The Toronto Hospital. grade fashion via the aortic root or in a retrograde fashion
via the coronary sinus.
In all patients, the heart was arrested with an aortic root
Methods
infusion of high potassium (27 mEq/L) blood cardioplegic
Patient population. Preoperative, perioperative, and solution. Cardioplegia was maintained with a low potas-
postoperative data were collected prospectively on all sium formulation (15 mEq/L). Proximal and distal anas-
patients undergoing isolated coronary artery bypass graft- tomoses were constructed during a single prolonged cross-
ing between July 1, 1990, and December 31, 1993, at The clamp period. 4 A left internal thoracic artery graft was
Toronto Hospital. The preoperative characteristics of the used in 3789 (83%) patients. Cardiac output was mea-
4558 consecutive patients are shown in Table I. sured with a thermodilution catheter placed percutane-
Operative technique. After median sternotomy and ously via the internal jugular vein into the pulmonary
heparinization, cardiopulmonary bypass was established artery. 5
with a single two-stage right atrial cannula and an ascend- Patients in whom weaning from cardiopulmonary by-
ing aortic cannula. During bypass, the hematocrit was pass was ditficult or in whom inadequate cardiac perfor-
maintained between 20% and 25%, pump flow rates mance developed in the intensive care unit had an in-
between 2.0 and 2.5 L/min per square meter, and mean traaortic balloon pump (Datascope Corporation, Paramus,
arterial pressures between 50 and 60 mm Hg by use of N.J.) inserted percutaneously via the common femoral ar-
sodium nitroprusside or phenylephrine hydrochloride as tery. Patients with less severe hemodynamic compromise
required. In elderly patients or in patients with carotid received inotropic medication.
3. The Journal of Thoracic and
40 Rao et al. Cardiovascular Surgery
July 1996
Study design. This study represents a retrospective t tests. Logistic models for each outcome variable were
analysis on data gathered in a prospective fashion and constructed with the use of methods described by Hosmer
included in a database registry. Multivariable analyses and Lemeshow. 9 Each prognostic variable was carefully
were used to determine the independent predictors of evaluated by the appropriate univariate test. Variables
outcomes. Comparisons of baseline, operative, and post- were selected for inclusion in a multivariable model if
operative data were made between patients in whom the their univariatep value was less than 0.25 or if the variable
outcome of interest occurred and patients in whom it did was of known clinical importance but failed, univariately,
not. to achieve the critical alpha level.
Definitions of variables. Appendix A gives a definition Models were fit and the best model for each outcome
of all preoperative variables. variable was determined by (1) an examination of the
Study outcomes. Low cardiac output syndrome was Wald statistic for each variable 9 and (2) a comparison of
diagnosed if the patient required an intraaortic balloon each estimated coefficient with the coefficient from the
pump either in the operating room or in the intensive care univariate model that contained only that variable. Coef-
unit because of hemodynamic compromise. Patients who ficients that changed markedly in magnitude indicated
had a balloon pump inserted preoperatively because of that one or more of the excluded variables were important
either ischemic chest pain or hemodynamic dysfunction in the adjustment of the effect of the remaining variables
were believed to have a postoperative low cardiac output in the model and an effort was made to refit the model. 7
syndrome if, in addition to the balloon pump, they also The next step in determining the best multivariable
required inotropic medication. Low cardiac output syn- model was to examine the goodness-of-fit statistic. Good-
drome was also diagnosed if the patient required inotropic ness of fit assessed the effectiveness of the model in
medication to maintain the systolic blood pressure greater describing the outcome variable. In addition, differences
than 90 mm Hg and the cardiac output greater than 2.2 between the observed data and the estimated values (the
L/rain per square meter for at least 30 minutes in the residual) for each covariate pattern were calculated by the
intensive care unit after correction of all electrolyte or Pearson or Hosmer-Lemeshow X2 statistic.9 The null
blood gas abnormalities and after adjusting the preload to hypothesis for goodness of fit claims that there are no
its optimal value. 6 Afterload reduction was also attempted significant differences between the predicted outcomes
when possible. Patients received either dopamine hydro- and the observed data. Therefore a probability greater
chloride, dobutamine hydrochloride, amrinone, or epi- than 0.05 indicates acceptance of the null hypothesis and
nephrine. We believe that prolonged treatment with ino- a valid model.
tropic medication may augment perioperative ischemic The final approach to determining the best model for
injury]' 8 Therefore inotropic medication was avoided each outcome variable was to examine the receiver oper-
when possible and was used only in patients who had mild ator characteristic (ROC) curve for each model. ROC
and transient hemodynamic compromise. An intraaortic curves are usually used to evaluate and compare an
balloon pump was inserted in patients who had moderate operator or diagnostic test with a "gold standard" and to
or severe hemodynamic compromise. Patients who re- explore the trade-offs between sensitivity and specificity
ceived less than 4 pg/kg of dopamine to increase renal for a test. a°' 11 Tests that discriminate well will crowd the
perfusion were not considered to have low cardiac output curve toward the upper left corner. The overall accuracy
syndrome. Patients who received vasoconstricting medica- of a test can be described as the area under the curve;
tion because of a high cardiac output (->2.5 L/rain per increasing the area under the curve corresponds to a
square meter) and low peripheral resistance were not better test because it optimizes the sensitivity and speci-
considered to have low cardiac output syndrome. ficity.x2, 13 When calculated in the BMDP LR program
Operative mortality and MI. Operative mortality was (BMDP Statistical Software Inc., Los Angeles, Calif.), n
defined as any death that occurred within 30 days of the ROC curve is independent of both the cut-point
operation or during the same hospital admission. A criteria (predicted probabilities) and the prevalence of the
perioperative MI was documented when a new Q wave outcomes. This independence allows comparison of the
was found on the postoperative electrocardiogram. An MI ROC area of different study populations where sensitivity
was also diagnosed if the postoperative electrocardiogram and specificity would be distorted by differences in the
had a new left bundle branch block, loss of R wave prevalence of the outcomes of interest. Therefore we used
progression, or new ST and T wave changes if accompa- these curves to provide an additional "diagnostic" tool to
nied by a rise in the level of the MB isoenzyme of creatine determine the optimum model for our binary outcome
kinase (CK-MB) greater than 50 U/L and if the CK- variables.
MB/CK ratio was greater than 5%. An antibody inhibition The internal validity of the model was assessed by use of
technique was used to measure the CK-MB level. The a bootstrap method in which the regression coefficients for
highest postoperative CK-MB value was recorded and the entire data set were correlated with the regression
expressed as a fraction of total CK if a perioperative coefficients of a test data set. The test data set was derived
ischemic event was suspected clinically. This definition of as a subpopulation of the entire data set.
perioperative MI requires electrocardiographic changes
and therefore may underestimate this outcome. Results
Statistical analysis. Statistical analysis was done with
the SAS program (SAS Institute, Cary, N.C.). Categorical T h e p r e o p e r a t i v e characteristics o f the e n t i r e
data were analyzed by a )~2 or Fisher's exact test where p a t i e n t p o p u l a t i o n a r e listed in T a b l e I. T h e overall
appropriate. Continuous data were analyzed by two-tailed m o r t a l i t y r a t e was 2.4% (n = 109). L o w c a r d i a c
4. The Journal of Thoracic and
Cardiovascular Surgery Rao et aL 41
Volume 112, Number 1
output syndrome developed in 412 patients (9.1%). Table II. Operative data
Table II compares the operative data for patients in P
whom low cardiac output syndrome developed with No LOS LOS Value
data for those patients in whom it did not. Patients No. of patients 4146 (91%) 412 (9%)
in whom low cardiac output syndrome developed Age (yr) 61.3 ± 9.6 63.6 ± 9.6 <0.001
were older (64 versus 61 years, p < 0.001) and had Diseased vessels
more extensive coronary artery disease (p < 0.001). 1 286 (7%) 22 (5%) 0.0012
2 1011 (24%) 72 (18%)
There were no significant differences in the number 3 2844 (69%) 315 (77%)
of bypass grafts constructed between the two groups. Grafts
Complete revascularization was accomplished in 1 72 (2%) 10 (2%) 0.660
4193 (92%) patients. The operative mortality rate in 2 482 (12%) 51 (12%)
patients in whom complete revascularization was 3 1440 (35%) 138 (33%)
4 1778 (43%) 177 (43%)
achieved was 2.3% compared with 3.9% in patients 5 374 (9%) 36 (9%)
in whom revascularization was not complete (p = Pump time (min) 85 ± 24 110 ± 39 <0.001
0.068). The prevalence of low cardiac output syn- Crossclamp time 60 ± 18 67 ± 27 <0.001
drome was 8.1% in patients in whom revasculariza- (rain)
tion was complete versus 14.6% in patients in whom Days of ventilator 1.1 _+ 2.5 2.9 ± 5.0 <0.001
support
it was not (p < 0.001). Days in ICU 2.2 -- 3.3 5.0 ± 6.3 <0.001
The left anterior descending artery (LAD) terri- Days in hospital 9.9 _+ 9.2 13.8 +- 12.4 <0.001
tory was revascularized in 99.6% of the patients with CK (units) 897 _+ 769 1429 -+ 1309 <0.001
LAD disease. Similarly, the territories of the cir- CK-MB (units) 41 + 37 83 + 102 <0.001
cumflex and right coronary arteries were revascular- Percent CK-MB 5.9 ± 9.9 6.7 ± 6.4 <0.001
Periop. MI 74 (1.8%) 59 (14.3%) <0.001
ized in 96.2% and 94.7% of the respective patients Stroke 47 (1.1%) 14 (3.4%) <0.001
with disease in those territories. Mortality 39 (0.9%) 70 (16.9%) <0.001
Patients in whom low cardiac output syndrome
LOS, Low cardiac output syndrome; ICU,, intensive care unit.
developed had longer cardiopulmonary bypass
times, longer aortic crossclamp times, a longer post-
operative intensive care unit stay, more days of (10%, OR 1.3). Table IV presents the regression
ventilatory support, a longer hospital stay, and a coefficients, their standard errors derived from the
higher postoperative CKMB level. Patients in whom logistic regression analysis, the ORs, the 95% con-
low cardiac output syndrome developed had a fidence intervals (95% CIs) for the ORs, the im-
higher mortality rate (17%) than patients in whom it provement X2 p value, and the goodness-of-fit p
did not develop (1%, p < 0.001). Patients in whom value for the nine independent predictors. The
low cardiac output syndrome developed were more predictive probability of the development of low
likely to have a perioperative MI (14.3% versus cardiac output syndrome can be calculated by the
1.8%,p < 0.001). formula P = e~/(1 - e*), where x is the sum of the
Predictors of low cardiac output syndrome. Figs. regression coefficients (see Appendix B). Fig. 3
1 and 2 and Table III illustrate the univariate results depicts the predicted probability of low cardiac
for the multivariable predictors of low cardiac out- output syndrome (abscissa) versus the logit score
put syndrome. Stepwise logistic regression analyses (ordinate) for several combinations of covariate
identified nine independent predictors of postoper- patterns for low cardiac output syndrome. This
ative low cardiac output syndrome (percentage in figure can be used to determine the probability of
whom low cardiac output syndrome developed in low cardiac output syndrome for an individual pa-
parentheses) and the factor-adjusted odds ratio tient.
(OR) associated with each predictor: (1) left ven- There were 133 patients (2.9%) who had a peri-
tricular ejection fraction less than 20% (27%, OR operative MI. The operative mortality rate was
5.7); (2) repeat operation (25%, OR 4.4); (3) emer- 21.8% in this group of patients compared with 1.8%
gency operation (27%, OR 3.7); (4) female gender in patients who did not have an infarct. Patients with
(16%, OR 2.5); (5) diabetes (13%, OR 1.6); (6) age low cardiac output syndrome had a significantly
older than 70 years (13%, OR 1.5); (7) left main higher prevalence of perioperative MI (14.3% ver-
coronary artery disease (12%, OR 1.4); (8) recent sus 1.8%, p < 0.001). Conversely, patients who had
MI (16%, OR 1.4); and (9) triple-vessel disease a perioperative MI had a 44% prevalence of low
5. The Journal of Thoracic and
42 R a o et al. Cardiovascular Surgery
July 1996
35 [ . P < 0.001
• LOS [] OM
[
30 I *
27 27
25
z 20
15 15
10 8
0
1 2 3 4 N Y 2 3
LV G R A D E REDO TIMING
20
*p< 0.001
• LOS [] OM +p< 0.05
16
15
+
13 13
12
10
7 +
5
0
M F N Y N Y N Y
GENDER DIABETES AGE>70 LEFT MAIN
Fig. 1. Univariate results of multivariable predictors of low cardiac output syndrome (LOS) and operative
mortality (OM). Left ventricular grade (LV GRADE) designated by 1, ejection fraction 60%; 2, ejection
fraction 40% to 59%; 3, ejection fraction 21% to 39%; or 4, ejection fraction 20%. Repeat operation
(REDO), that is, previous aorta-coronary bypass, noted as yes (Y) or no (N). Timing of operation
designated by 1, elective operation; 2, operation during same hospitalization as cardiac catheterization or
cardiac event (semielective); or 3, urgent operation within 72 hours of cardiac event. Gender noted as male
(M) or female (F). Diabetes; age younger than 70 years; and left main coronary artery disease (LEFT
MAIN), that is, significant (greater than 50%) stenosis of left main coronary artery, noted as yes or no.
6. The Journal of Thoracic and
Cardiovascular Surgery Rao et aL 43
Volume 112, Number 1
'° I , • LOS [ ] OM I .po.oo,
+p< 0.01
15 8 16
i 10 +
10 l0 I
8
5 + +
N Y N Y N Y
RECENT MI TRIPLE VESSEL DISEASE HYPERTENSION
Fig. 2. Univariate results of multivariable predictors of low cardiac output syndrome (LOS) and operative
mortality (OM). Recent MI, that is, MI within 30 days before operation; triple-vessel disease; and
hypertension noted as yes (Y) or no (N).
cardiac output syndrome compared with 8% in p < 0.001); in patients with diabetes (3.8% versus
patients who did not have an infarct. 2.0%, p = 0.001); in female patients (3.8% versus
Operative mortality. There were 109 operative 2.0%,p = 0.002); in patients with left main coronary
deaths in this population. Among patients in whom artery disease (3.6% versus 2.1%, p = 0.014); in
low cardiac output syndrome developed (n = 412) patients with hypertension (3.0% versus 1.8%, p =
there were 70 deaths (17%) compared with 39 0.006); in patients who had an MI less than 30 days
deaths (0.9%) in those in whom low cardiac output before operation (4.0% versus 2.1%,p = 0.002); in
syndrome did not develop (n = 4146). The mean patients with chronic obstructive pulmonary disease
postoperative length of stay for patients who died (3.4% versus 2.2%, p = 0.036); and in patients with
after the development of low cardiac output syn- New York Heart Association class IV disease (3.6%
drome was 7.4 _+ 11.3 days (median 3.5 days, range versus 1.3% in New York Heart Association class I,
0 to 53 days). The mean postoperative length of stay p = 0.002).
for patients who died without having the develop- The multivariable predictors of operative mortal-
ment of low cardiac output syndrome was 23.1 ___ ity were (1) left ventricular ejection fraction less
26.6 days (median 12.5 days, range 0 to 84 days). than 20% (OR 8.1); (2) repeat operation (OR 4.9);
The operative mortality rate was significantly (3) peripheral vascular disease (OR 2.8); (4) age
higher by univariate analysis in patients with a left older than 70 (OR 2.8); (5) emergency operation
ventricular ejection fraction less than 20% (10.9% (OR 2.7); (6) diabetes (OR 1.7); (7) female gender
versus 1.2% with left ventricular ejection fraction (OR 1.7); (8) left main coronary artery stenosis (OR
greater than 60%, p < 0.001); in patients undergo- 1.5); and (9) hypertension (OR 1.4). Table V pre-
ing repeat operation (7.5% versus 2.0%,p < 0.001); sents the regression coefficients, their standard er-
in patients with peripheral vascular disease (6.6% rors derived from the logistic regression analysis, the
versus 1.8%, p < 0.001); in patients older than age ORs, the 95% CIs for the ORs, the improvement X2
70 (5.0% versus 1.1% in patients younger than age p value, and the goodness-of-fit p value for the nine
50, p < 0.001); in patients undergoing emergency independent predictors. The 95% CIs for left main
operation (6.6% versus 1.7% in elective operation, coronary artery stenosis and hypertension both in-
7. The Journal of Thoracic and
44 Rao et al. Cardiovascular Surgery
July 1996
Table III. Univariate analysis for low cardiac output syndrome and operative mortality
LOS No LOS Mortality
P Value p Value
N % N % (LOS) N % (034)
No. of patients 412 9 4146 91
LVEF
>60% 87 6 1443 94 <0.001 19 1 <0.001
40%-60% 146 8 1780 92 44 2
20%-40% 139 15 817 85 30 3
<20% 40 27 106 73 16 11
Repeat operation 82 25 253 75 <0.001 25 8 <0.001
No Repeat 330 8 3893 92 84 2
Timing <0.001 <0.001
Elective 169 6 2451 94 45 2
Semielective 112 10 1018 90 35 3
Urgent 90 14 567 86 19 3
Emergency 41 27 110 73 10 7
Sex
Male 271 7 3402 93 <0.001 75 2 0.002
Female 141 16 744 84 34 4
Diabetes 137 13 949 87 <0.001 41 4 0.001
No diabetes 275 8 3197 92 68 2
Age
<70 283 8 3261 92 <0.001 58 2 <0.001
->70 129 13 885 87 51 5
Left main CAD
Y 94 12 714 88 0.005 29 4 0.014
N 318 9 3432 91 80 2
Recent MI
Y 112 16 580 84 <0.001 28 4 0.002
N 300 8 3566 92 81 2
Triple-vessel CAD
Y 315 10 2759 90 0.002 80 3 0.651
N 94 7 1391 93 29 2
Hypertension 230 10 2107 90 0.053 70 3 0.006
No hypertension 182 8 2039 92 39 2
LOS, Low cardiac output syndrome;OM, operative mortality; LVEF, left ventricular ejection fraction; Y, yes; N, no; recent MI, MI within 30 days before
operation; CAD, coronary artery disease.
I
Table IV. Multivariable analysis for low cardiac output syndrome
Regression Improvement GOF
Variable coefficient SE OR 95% CI X2 p value p value
Constant -3,866 0.166
LVEF
40%-60% 0.1777 0.146 1.19 0.89-1.59
20%-40% 0.8614 0.153 2.37 1.75-3.19
<20% 1.7410 0.232 5.70 3.62-8.99 <0.001 0.031
Repeat operation 1.4770 0.151 4.38 3.26-5.89 <0.001 0.277
Timing of operation
Urgent 0.2451 0.128 1,28 0.99-1.64
Emergency 1.3120 0.237 3.72 2.34-5.91 <0.001 0.966
Female gender 0.9287 0.122 2.53 1.99-3.22 <0.001 0.825
Diabetes 0,4644 0.119 1.59 1.26-2.01 <0.001 0.983
AGE ->70 0.3691 0.122 1.45 1.14-1.84 0.001 0.990
Left main CAD 0,3500 0.133 1.42 1.09-1.84 0.011 0.993
Recent MI 0.3241 0.148 1.38 1.04-1.85 0.023 0.994
Triple-vessel disease 0.2841 0.130 1.33 1.03-1.71 0.026 0.996
SE, Standard error; GOF, goodness of fit; LVEF, left ventricular ejection fraction; CAD, coronary artery disease; Recent MI; MI within 30 days before
operation.
8. The Journal of Thoracic and
Cardiovascular Surgery Rao et al. 45
Volume 112, Number 1
%
90 [] 95% Confidence Interval
80
70
60
50-
40-
30-
20-
10-
0
-4
Logit Score
LVGRADE 1 2 2 12 1 1 2 33 1 3 32 332 3 3 42 4323 3 3 34 4 4 4
ACBREDO 0 0 0 00 0 0 0 00 0 0 01 001 1 1 110110 10 1101 0
SEX MM MMMM FMMM FM FMMFMM MMM F F M F M FMM FM F
TIMING E E S S E S S S SES S EESSS E S EUESUU SU USUU U
DIABETES 0 0 0 0 0 1 0 0 1 100111001 0 001011 1 1 110 0 1
A G E > 70 0 0 0 1 0 0 0 0 0 11 0001110 1 000100 1 1 01 I 0 1
L MAIN DISEASE 0 0 0 0 0 0 0 1 0 001001110 0 011000 1 0 0010 0
RECENTMI 0 0 0 01 0 0 ! 0 01 1 000000 1 000011 1 1 111 1 1
TVD 0 0 0 01 1 0 1 0 001 011011 0 011011 1 1 I101 1
Fig. 3. Predictive probability of low cardiac output syndrome after coronary artery bypass grafting. Left
ventricular grade (LV GRADE) scored from i to 4. Repeat aorta-coronary bypass (ACB REDO), diabetes,
age older than 70 years, left main coronary artery disease (L MAIN DISEASE), recent MI, and triple-vessel
disease (TVD) scored 0 for no, 1 for yes. M, Male; F, female; E, elective; S, semielective; U, urgent.
Table V. Multivariable analysis for operative mortality
Regression Improvement GOF
Variable coefficient SE OR 95% CI Xe p value p value
Constant -5.760 0.316
PVD 1.0330 0.215 2.81 1.84-4.28 <0.001 1.000
LVEF
40%-60% 0.4847 0.284 1.62 0.93-2.83
20%-40% 0.7036 0.306 2.02 1.11-3.68
<20% 2.0920 0.371 8.10 3.91-16.80 <0.001 0.448
Repeat operation 1.5810 0.251 4.86 2.97-7.95 <0.001 0.357
Age >-70 1.0250 0.208 2.79 1.85-4.19 <0.001 0.439
Female gender 0.5178 0.227 1.68 1.08-2.62 0.004 0.214
Diabetes 0.5560 0.212 1.74 1.15-2.64 0.009 0.637
Timing of operation
Urgent 0.1317 0.217 1.14 0.75-1.75
Emergency 0.9907 0.390 2.69 1.25-5.79 0.039 0.230
Left main CAD 0.4341 0.232 1.54 0.98-2.43 0.059 0.660
Hypertension 0.3542 0.212 1.43 0.94-2.16 0.091 0.682
SE, Standard error; GOF, goodness of fit; PVD, peripheral vascular disease; LVEF, left ventricular ejection fraction; CAD, coronary artery disease.
clude unity, which indicates that they are weak The area under the ROC curve for low cardiac
predictors of operative mortality. output syndrome is similar to that for operative
Fig. 4 illustrates the predicted operative mortality mortality (74% versus 76%), which indicates that
for all combinations of the nine independent pre- both models are similar in terms of their sensitiv-
dictors. Fig. 5 depicts the R O C curves for both low ity and specificity to detect their respective out-
cardiac output syndrome and operative mortality. comes.
9. The Journal of Thoracic and
46 Rao et aL Cardiovascular Surgery
July 1996
%
95% Confidence Interval
70
60
50
40
30
20
10
0
-6 -4 -2 0
Logit Score
PVD 00 0 0 000 10100000001100011101011 00111 1 1 1 1
LVGRADE 11 1 1 13 1 11113221322 1324412424'33 34344 2 3 3 4
ACB REDO 00 0 0 000 00000001000001001010001 10100 1 1 0 1
AGE > 70 00 0 0 000 00011110111 110000100010 1111 0 1 1 1 0
SEX MMM FMMMMMMMMMMMMMMFMMMMMFMFFMMMFMMFMF FM
DIABETES 00 0 0 101 01000001100010100000110 10010 1 0 1 0
TIMING ES E E SSE SEESEESEESE SSSSSESEUEES SSESU S S U U
L MAIN DISEASE 00 0 0 001 01110000010011001001111 11000 0 0 1 0
HYPERTENSION 00 1 0 001 010001100100011011011 11 01101 1 1 1 0
Fig. 4. Predictive probability of operative mortality after coronary artery bypass grafting. Peripheral
vascular disease (PVD), repeat aorto-coronary bypass (ACB REDO), age older than 70 years, diabetes, left
main coronary artery disease (L MAIN DISEASE), and hypertension scored 0 for no, 1 for yes. Left
ventricular grade (LV GRADE) scored from 1 to 4. M, Male; F, female; E, elective; S, semielective; U,
urgent.
Discussion sures impractical in modern studies of myocardial
An increasing number of patients with high-risk protection.
conditions are undergoing coronary artery bypass For example, to detect a 20% reduction in the
grafting. 1 The extension of cardiac operation to operative mortality rate from 2% to 1.6%, one
patients at higher risk is a result of improved would need to study 8504 patients to achieve a 5%
operative techniques and perioperative myocardial level of significance with a power of 80%. To detect
protection. Cardiologists and surgeons have ex- a 20% reduction in the prevalence of perioperative
tended the benefits of coronary artery bypass to MI from 3% to 2.4%, one would require 5618
patients at higher risk as the risks of operation have patients. A similar 20% decrease in the prevalence
decreased) 4 To continue to reduce perioperative of low cardiac output syndrome from 10% to 8%
morbidity and mortality, cardiac surgeons must de- would require 1577 patients to achieve a 5% level of
vise strategies to improve myocardial protection in significance. Patients in whom low cardiac output
patients at high risk. syndrome develop have a significantly higher prev-
Traditionally, the results of coronary artery by- alence of perioperative MI and a higher operative
pass have been evaluated by operative mortality and mortality. Thus the development of low cardiac
perioperative MI. 14-16Low cardiac output syndrome output syndrome represents either inadequate re-
is another clinical outcome that can be used to vascularization or inadequate myocardial protection
assess the efficacy of perioperative myocardial pro- and may act as a marker of intraoperative myocar-
tection. Two large randomized clinical trials failed dial injury. Our results indicate that the territory
to show any difference in perioperative mortality or supplied by the LAD was revascularized in more
MI between the treatment groups. 2' 3 The low rates than 99% of patients with disease in that distribu-
of operative mortality and the problems inherent in tion. Revascularization was incomplete in the terri-
uniformly defining and identifying perioperative in- tory of the right coronary artery in 5% of the
farction have made the use of these outcome mea- patients with right coronary artery disease. These
10. The Journal of Thoracic and
Cardiovascular Surgery Rao et al. 47
Volume 112, Number 1
Low Output Syndrome Operative Mortality
Sensitivity (%) Sensitivity (%)
100 100-
90 90
80 80
70 70
60 60
50 50
40 40
30 30
20 20
10 10
0 OT
0 20 40 60 80 100 0 20 40 60 80 100
100 - Specificity (%) I00 - Specificity (%)
Fig. 5. ROC curves of predictive models for low cardiac output syndrome (left) and operative mortality
(right).
patients likely represent a subpopulation with a Poor ventricular function. Poor left ventricular
previous inferior MI and an occluded coronary function continues to be the most important predic-
artery. Despite having preserved left ventricular tor of postoperative morbidity and mortality. Pa-
function, these patients were still at risk for the tients with poor ventricular function have a limited
development of postoperative low cardiac output margin for myocardial protection. 16 However, the
syndrome. dysfunctional myocardium may not be irreversibly
Diagnosis. A diagnosis of low cardiac output damaged and may be "stunned" or "hibernating."
syndrome required the active intervention of the Revascularization of the reversibly injured heart
cardiac surgeon, and at our institution this interven- may result in improved left ventricular performance.
tion represented a failure of our usual perioperative Cold injury or inhomogeneous cardioplegic delivery
strategy. Thus the diagnosis of low cardiac output may exacerbate perioperative ischemic injury and
syndrome was a reproducible clinical outcome. The result in inadequate early postoperative ventricular
Warm Heart Investigators established an indepen- function. 17 Prolonged reperfusion with a terminal
dent committee to evaluate postoperative low car- "hot shot" of cardioplegic solution may restore
diac output syndrome. 2 Their criteria for diagnosis function in patients with poor ventricular function, is
were similar to ours and again support the concept Warm cardioplegia may improve postoperative left
that this syndrome can be used as an objective ventricular function in patients with high-risk con-
measurement of perioperative myocardial injury. ditions, inasmuch as we have previously shown that
This study identified nine independent preopera- warm cardioplegia improves ventricular function in
tive predictors of low cardiac output syndrome after patients at low risk undergoing elective opera-
coronary artery bypass grafting (Figs. 1 and 2). The tions. 17 Unfortunately, some patients will continue
potential causes for inadequate postoperative car- to have poor ventricular function after operation
diac performance are not well established. and the role of myocardial protection in these
11. The Journal of Thoracic and
48 Rao et aL Cardiovascular Surgery
July 1996
patients may be to limit the extent of perioperative warm (37° C) cardioplegia and improved left ven-
injury. tricular function compared with cold (10 ° C) blood
Reoperation. Patients undergoing repeat opera- cardioplegia. 22
tions represent a challenge for intraoperative man- Female gender. The Coronary Artery Surgery
agement. Patients undergoing reoperation have Study investigators reported female gender to be
more diffuse disease and are at risk of having a associated with higher perioperative morbidity and
shower of emboli from their previous bypass grafts. mortality. 15 The authors postulated that this in-
The management of patent grafts is difficult. The creased morbidity was a result of the smaller size of
study by Lytle and associates 19 from the Cleveland the coronary vessels and the higher risk of graft
Clinic revealed that the operative mortality rate in thrombosis. A recent review from our institution 22a
patients undergoing repeat coronary artery bypass revealed that female patients had a higher preva-
was 4.3%. They found that patients with stenoses in lence of operative mortality and postoperative low
vein grafts to the LAD region had decreased sur- cardiac output syndrome. The predictors of opera-
vival. However, there were no in-hospital deaths tive mortality and postoperative low cardiac output
among patients with totally occluded vein grafts or syndrome were similar for both men and women.
patent internal thoracic artery grafts to the LAD Small body size was an independent risk factor for
region. The authors speculated that the retrograde postoperative morbidity. In patients of similar body
introduction of cardioplegic solution significantly size, female gender was an independent risk factor
lowered the operative mortality rate of repeat oper- for low cardiac output syndrome and operative
ation as a direct consequence of reducing athero- mortality.
sclerotic emboli from previous vein grafts. 19 Diabetes mellitns. Patients with diabetes may
Urgent operation. Patients who require urgent have more diffuse atherosclerotic disease, which
operation because of unstable angina may benefit may limit complete revascularization. In addition,
most from improved strategies of myocardial pro- patients with diabetes may have silent ischemia and
tection. Prolonged preoperative ischemia may de- be seen for operation after extensive MI or may
plete metabolic reserves. Substrate enhancement have diffuse coronary artery disease. Cardioplegic
with Krebs cycle intermediates 2°'21 may benefit protection may pose a problem in patients with
these patients. Rousou and associates 21 showed that diffuse coronary disease. Proximal coronary lesions
cardioplegic enhancement with Krebs cycle interme- may impair antegrade delivery of cardioplegic solu-
diates such as glutamate, malate, succinate, and tion and venovenous and thebesian shunting may
fumarate preserved high-energy phosphates during reduce the retrograde delivery of cardioplegic solu-
ischemic arrest but that this preservation did not tion. Homogeneous distribution of cardioplegic
extend to the reperfusion period. To date the effec- solution may improve intraoperative myocardial
tiveness of substrate-enhanced cardioplegia remains protection in these patients. A recent study by
controversial. The use of warm rather than cold Hayashida and associates 23 showed that a combina-
cardioplegia may help to resuscitate the ischemic tion of antegrade and retrograde cardioplegic solu-
myocardium. Cold cardioplegia reduces myocardial tion delivery may provide the best protection by
oxygen consumption and lactate production, but improving the distribution of cardioplegic solution.
delays the recovery of oxidative metabolism and Intermittent antegrade infusions after each period
ventricular function. Cold cardioplegia has the ad- of continuous retrograde cardioplegic solution de-
vantage of improved protection to areas that are livery resulted in the washout of accumulated lac-
difficult to perfuse because of coronary obstructions. tate. This finding suggested that the two directions
Warm cardioplegia may resuscitate the ischemic of cardioplegic solution delivery perfuse different
myocardium if it can be delivered uniformly and myocardial territories. Combining the two tech-
continuously. Discontinuation of normothermic niques may result in a more homogeneous distribu-
blood cardioplegic solution delivery to permit visu- tion of cardioplegic solution2
alization of the distal anastomosis may result in Advanced age. Elderly patients continue to be at
ischemic anaerobic metabolism. Perhaps the ideal high risk for postoperative complications (Fig. 2). At
cardioplegic temperature lies between the two ex- our institution an increasing proportion of patients
tremes. We have recently reported the use of "tep- older than age 70 are presenting for surgical treat-
id" (29 ° C) cardioplegia. 22 Tepid cardioplegia re- ment, but the prevalences of perioperative infarc-
duced lactate and acid production compared with tion and operative mortality have decreased during
12. The Journal of Thoracic and
Cardiovascular Surgery R a o et al. 49
Volume 112, Number 1
the past decade. 24 The elderly are at increased risk sonography to detect atherosclerotic plaques to
not only because of the obvious effects of aging but aid aortic cannulation has been advocated by
also because of the increased prevalence of comor- Barzilai and colleagues. 26
bid conditions in this population. Misare, Kruken- Models. Fig. 3 illustrates the predictive probabil-
kamp, and Levitsky25 showed an age-dependent ity of the development of low cardiac output syn-
sensitivity to myocardial ischemia in an ovine model. drome on the basis of data from our patient
These authors termed this phenomenon the senes- population. Fig. 4 illustrates the predictive prob-
cent myocardium. Thus, independent of other co- ability of operative mortality after aorta-coronary
morbid conditions, elderly patients may be at in- bypass.
creased risk for perioperative myocardial injury Greenland 27 concluded that both stratified (pop-
because of their senescent myocardium. ulations stratified on the basis of risk) and modeling
Left main coronary artery disease. The presence (predictive models derived from multivariable anal-
of left main coronary artery disease is no longer as yses) techniques to analyze populations have limita-
important a predictor of operative mortality as it tions based on the control of variable selection and
was previously.1 Although left main stenosis was the size and quality of data sets. Neither approach
selected as an independent predictor of operative can compensate for fundamental methodologic er-
mortality, the confidence interval for the OR in- rors such as misclassifications, selection bias, or lack
cludes one, which indicates that left main disease of statistical power to address the questions of
may not be a major predictor of operative mortality. interest. Greenland 27 therefore concluded that
However, in this study, left main coronary artery more effort should be put into correctly interpreting
disease was still an independent risk factor for the and intelligibly presenting modeling results to re-
development of low cardiac output syndrome. Im- flect these underlying errors. An evaluation of the
provements in myocardial protection may have com- ability of a model to correctly represent the under-
pensated for the increased risk in left main coronary lying data set is mandatory when presenting regres-
artery disease. The use of retrograde or combination sion analyses. The Pearson or Hosmer-Lemeshow
cardioplegic techniques may further reduce the im- statistics yield a measure of the goodness of fit for a
portance of left main disease on the outcome of low particular model and can be used to compare mod-
cardiac output syndrome. els derived from the same underlying data. The
Recent MI and triple-vessel disease. Patients goodness-of-fit p values for our final models of low
with an MI within 30 days of operation were at cardiac output syndrome and operative mortality
slightly higher risk for the development of low were greater than 0.99 and 0.65, respectively, and
cardiac output syndrome. Similarly, patients with suggested an excellent agreement between observed
triple-vessel disease were at higher risk for the and predicted values. The internal validity of our
development of low cardiac output syndrome. Al- models was evaluated with use of a bootstrap
though both of these risk factors were selected as method. The regression coefficients between the
independent risk factors for the development of low whole data set and the test data set correlated for
cardiac output syndrome, the confidence interval of both operative mortality (ra = 0.981,p < 0.001) and
their ORs approached one. Thus, although statisti- low cardiac output syndrome (r2 = 0.987,p < 0.001).
cally significant, these risk factors are weak predic- These results lend further support to the validity of
tors of low cardiac output syndrome. these models.
Hypertension and peripheral vascular disease. The ROC curves are another tool to evaluate the
Hypertension and peripheral vascular disease ability of a model to accurately represent the under-
were independent predictors of mortality but not lying data. The advantage of the ROC curve is that
of low cardiac output syndrome. These risk factors it is independent of the prevalence of the outcome
predispose patients to stroke and mortality may of interest and thus can be used to compare logistic
have been a result of noncardiac causes. There- models derived from different data sets with varying
fore these variables did not predict postoperative levels of incidence and prevalence. The areas under
low cardiac output syndrome. Strategies to mini- the ROC curve for the low cardiac output syndrome
mize the impact of these variables include im- and operative mortality models were 74% and 76%,
proved management of perioperative blood pres- respectively (Fig. 5). These figures can be used to
sure and minimal manipulation of the aorta compare our logistic models with other models
during operation. The use of intraoperative ultra- derived from a different patient population. The
13. The Journal of Thoracic and
50 Rao et al. Cardiovascular Surgery
July 1996
larger the area under the ROC curve, the more balloon counterpulsation during early reperfusion after isch-
accurate the model is in predicting outcomes in the emic arrest of the heart. J Thorac Cardiovasc Surg 1987;93:
597-608.
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lying data or a result of inaccuracies in a poorly fit ogy: the essentials. Baltimore: Williams & Wilkins, 1988.
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Berkeley: University of California Press, 1992.
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and patient populations. Thus differences in predic- moto F, Edward H, Bugyi H. Benefits of normothermic
tive variables between patient populations can once induction of blood cardioplegia in energy-depleted hearts,
again be ascribed to either true differences between with maintenance of arrest by multidose cold blood car-
the populations or to inaccuracies in poorly fit dioplegic infusions. J Thorac Cardiovasc Surg 1982;84:667-
77.
models. The use of such objective criteria will
13. Sackett DL, Haynes RB, Tugwell P. Clinical epidemiology: a
alleviate the problem of different multivariable basic science for clinical medicine. Boston: Little Brown,
equations arising from the same data set. 2s' 29 1985.
This study presents the independent predictors of 14. Teoh KH, Christakis GT, Weisel RD, et al. Increased risk of
low cardiac output syndrome in 4558 consecutive urgent revascularization. J Thorac Cardiovasc Surg 1987;93:
291-9.
patients who underwent isolated coronary artery
15. Fisher LD, Kennedy JW, Davis KB, et al. Association of sex,
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nition of low cardiac output syndrome is objective bypass in the Coronary Artery Surgery Study (CASS). J
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Weisel. We also acknowledge the assistance of Ms. Susan cardioplegia (hot shot). J Thorac Cardiovasc Surg 1986;91:
Dougherty in the preparation of this manuscript. 888-95.
19. Lytle BW, Loop FD, Taylor PC, et al. The effect of coronary
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Left ventricular grade. Ejection fraction greater than
Appendixes 60% (grade 1), ejection fraction between 40% and 60%
Appendix A: Definitions of perioperative variables (grade 2), ejection fraction between 20% and 40% (grade
3), ejection fraction less than 20% (grade 4), as assessed
Elderly. Patients older than age 70 years.
by a single-plane contrast ventriculogram or by echocar-
Diabetes. A preoperative diagnosis of diabetes mellitus
diography or nuclear ventriculography if a contrast ven-
treated with insulin, oral hypoglycemic agents, or diet.
Triple-vessel disease. Critical lesions (greater than 50% triculogram was not done.
luminal narrowing) affecting the territories supplied by Appendix B. To calculate the predicted probability of
the right, LAD, and left circumflex coronary arteries. low cardiac output syndrome or operative mortality for a
Left main coronary artery disease. Greater than 50% given patient, start with the constant and then add the
stenosis of the left main coronary artery. regression coefficients that describe the patient's charac-
Peripheral vascular disease. Known carotid, aortoiliac, or teristics for a coefficient total (x). Then use the formulap
femoropopliteal disease or cases in which the patient had = e*/(1 + e~). For example, from Table IV the predicted
a previous carotid endartectomy or peripheral vascular probability of low cardiac output syndrome for a 72-year-
operation. old male patient with a left ventricular ejection fraction of
Transient ischemic attacks. A preoperative history of 35% and left main coronary artery disease but no diabe-
transient ischemic attacks, reversible ischemic neurologic tes, no previous coronary artery bypass grafting, and no
deficits, or stroke. recent MI undergoing urgent operation would be x =
Normothermia. Systemic temperature higher than 35 ° C -3.866 + 0.3691 + 0.8614 + 0.350 + 0 + 0 + 0 + 0 +
during cardiopulmonary bypass. 0.2451 - 2.0404; p = e2°4°4/(1 + e 2'°4°4) = 0.115 (or
Timing. Elective, same hospitalization, urgent (within 11.5%).