This presentation discusses the past, present, and future of cardiac biomarkers for diagnosing acute cardiac events like myocardial infarction. It reviews earlier biomarkers like CK-MB and LDH and the current gold standards of cardiac troponins. Emerging biomarkers discussed include H-FABP, GPBB, ST2, and microRNAs, which may allow for earlier diagnosis. The goals of using multiple biomarkers are to determine the presence, type, and severity of cardiac tissue damage. Overall, biomarkers have progressed from being used retrospectively to becoming a diagnostic standard and influencing treatment decisions.
Cardiac biomarkers have evolved over last 20 years. From enzymes like CPK,SGOT,LDH, the focus shifted to CPKMB mass & currently to high sensitive Troponins. Similarly the definition of AMI also evolved and included these markers in guidelines. Natriuretic peptides (BNP & Nt-proBNP) are good markers for heart failure. however, ACS in renal failure continues to have diagnostic challenges.
This document discusses various biomarkers for coronary artery disease and myocardial infarction. It begins by outlining existing diagnostic and prognostic biomarkers, and then describes several new biomarkers under investigation. These include biomarkers of biomechanical stress like BNP, biomarkers of neurohormonal activation like copeptin, and biomarkers of plaque instability like CRP. The document also discusses newer technologies like metabolomics and genetic biomarkers. Throughout, it provides details on each biomarker and their clinical significance.
cardiac bio markers are important diagnostic and prognostic tool in acute coronary syndrome. several new emerging bio markers are coming with more sensitivity and specificity.
Ultra high sensitivity troponins can detect troponin in healthy individuals and allow for earlier diagnosis of myocardial infarction. However, they have reduced specificity and may lead to overdiagnosis. Using troponins along with risk stratification tools like the TIMI score and serial measurements can help manage this. Studies show accelerated diagnostic pathways using high sensitivity troponins and risk scores safely reduce length of stays and admissions for approximately 40% of low-risk suspected acute coronary syndrome patients. Ongoing issues include safely managing intermediate-risk patients and addressing reduced specificity.
The document discusses strategies for early treatment of acute myocardial infarction. It provides evidence that pre-hospital thrombolytic therapy can significantly reduce mortality rates compared to in-hospital thrombolytic therapy by reducing treatment delays. Studies show administering thrombolysis within 30-60 minutes of symptoms onset can save 11-60 lives per 1000 patients. Combined strategies using both pre-hospital thrombolysis and immediate angioplasty have demonstrated high rates of coronary reperfusion and good long-term outcomes.
Primary PCI is the preferred treatment for STEMI, achieving success rates of around 90% compared to 50% for thrombolysis. While thrombolysis has mortality rates of 7-10% in trials and 10-17% in registries, primary PCI has lower mortality rates of 5% in trials and 5-9% in registries. The PRAGUE studies showed lower combined endpoints of death, re-infarction and stroke for primary PCI compared to thrombolysis. Guidelines now recommend primary PCI as the default reperfusion strategy for STEMI when it can be performed in a timely manner.
Cardiac biomarkers have evolved over last 20 years. From enzymes like CPK,SGOT,LDH, the focus shifted to CPKMB mass & currently to high sensitive Troponins. Similarly the definition of AMI also evolved and included these markers in guidelines. Natriuretic peptides (BNP & Nt-proBNP) are good markers for heart failure. however, ACS in renal failure continues to have diagnostic challenges.
This document discusses various biomarkers for coronary artery disease and myocardial infarction. It begins by outlining existing diagnostic and prognostic biomarkers, and then describes several new biomarkers under investigation. These include biomarkers of biomechanical stress like BNP, biomarkers of neurohormonal activation like copeptin, and biomarkers of plaque instability like CRP. The document also discusses newer technologies like metabolomics and genetic biomarkers. Throughout, it provides details on each biomarker and their clinical significance.
cardiac bio markers are important diagnostic and prognostic tool in acute coronary syndrome. several new emerging bio markers are coming with more sensitivity and specificity.
Ultra high sensitivity troponins can detect troponin in healthy individuals and allow for earlier diagnosis of myocardial infarction. However, they have reduced specificity and may lead to overdiagnosis. Using troponins along with risk stratification tools like the TIMI score and serial measurements can help manage this. Studies show accelerated diagnostic pathways using high sensitivity troponins and risk scores safely reduce length of stays and admissions for approximately 40% of low-risk suspected acute coronary syndrome patients. Ongoing issues include safely managing intermediate-risk patients and addressing reduced specificity.
The document discusses strategies for early treatment of acute myocardial infarction. It provides evidence that pre-hospital thrombolytic therapy can significantly reduce mortality rates compared to in-hospital thrombolytic therapy by reducing treatment delays. Studies show administering thrombolysis within 30-60 minutes of symptoms onset can save 11-60 lives per 1000 patients. Combined strategies using both pre-hospital thrombolysis and immediate angioplasty have demonstrated high rates of coronary reperfusion and good long-term outcomes.
Primary PCI is the preferred treatment for STEMI, achieving success rates of around 90% compared to 50% for thrombolysis. While thrombolysis has mortality rates of 7-10% in trials and 10-17% in registries, primary PCI has lower mortality rates of 5% in trials and 5-9% in registries. The PRAGUE studies showed lower combined endpoints of death, re-infarction and stroke for primary PCI compared to thrombolysis. Guidelines now recommend primary PCI as the default reperfusion strategy for STEMI when it can be performed in a timely manner.
Cardiac biomarkers are proteins released when heart muscle is damaged and can help diagnose and manage cardiovascular diseases. Commonly used biomarkers include cardiac troponins and natriuretic peptides. Troponins indicate heart muscle injury while natriuretic peptides reflect heart failure. High sensitivity troponin assays can detect very low levels and aid early diagnosis of heart attacks. Emerging biomarkers of inflammation like interleukin-6 may also provide prognostic information. Biomarkers are detected at different times after injury and combining their measurements over time can improve the assessment of patients with suspected cardiovascular issues.
Primary PCI involves performing urgent angioplasty and potentially stenting of the culprit artery in STEMI patients, with the goal of reopening the blocked vessel within 90 minutes of first medical contact. It is the preferred reperfusion strategy when it can be performed promptly by an experienced team. Factors such as patient age, time to treatment, comorbidities, and initial flow in the artery help determine whether primary PCI or thrombolysis is most appropriate. Optimal anticoagulation and antiplatelet regimens along with adjunctive therapies like manual thrombectomy can improve outcomes of primary PCI.
The CAPRIE study found that clopidogrel therapy resulted in a relative risk reduction of 8.7% compared to aspirin therapy for preventing cardiovascular events in patients with atherosclerosis, with fewer gastrointestinal hemorrhages. The CURE trial found that in patients with acute coronary syndrome receiving aspirin, pretreatment with clopidogrel followed by long-term therapy reduced major cardiovascular events compared to placebo. The CLASSICS trial found that clopidogrel had superior safety and tolerability to ticlopidine for antiplatelet therapy after coronary stenting, with comparable efficacy.
STEMI Late Presentation - Management and practical approachSatyam Rajvanshi
1) Late presenters of STEMI (over 12 hours) make up a significant portion of STEMI patients worldwide and in India.
2) Evidence suggests that while reperfusion therapy is not beneficial for late presenters, PCI may still allow for myocardial salvage even in occluded arteries up to 72 hours from symptom onset.
3) Guidelines vary in their recommendations for revascularization of late presenters but a practical approach is to consider early revascularization for stable patients within 72 hours while stress testing those presenting after 72 hours.
The document discusses various biomarkers used in the diagnosis and management of heart failure. It states that natriuretic peptides like BNP and NT-proBNP are the most widely used biomarkers for heart failure as they are accurate for establishing diagnosis, determining severity, and predicting prognosis. It describes the release and function of these peptides. It also mentions other biomarkers like cardiac troponins, inflammatory markers, neurohormonal factors, and matrix proteins that provide additional information on myocardial injury, inflammation, neurohormonal activation, and remodeling in heart failure. A multimarker approach may help better classify and risk stratify heart failure.
Acute Coronary Syndrome (ACS) refers to a spectrum of clinical presentations caused by acute coronary athero-thrombosis that obstruct myocardial blood flow. This includes ST-segment elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), and unstable angina. NSTEMI is diagnosed with elevated cardiac biomarkers and detected ischemia on electrocardiograms or stress tests. Treatment involves antithrombotic and anti-ischemic drugs to reduce ischemia and prevent clots. In some cases, coronary angiography and revascularization by percutaneous coronary intervention may be recommended.
Coronary bifurcation lesions are challenging to treat percutaneously and account for approximately 15% of PCIs. Interventions on bifurcations have lower success rates and higher complication rates than other lesions. The optimal strategy for treating bifurcations, whether provisional stenting of the main vessel with treatment of the side branch only if needed versus systematic two-stent techniques, is still debated. Several randomized trials have compared different approaches but longer-term data is still needed. Dedicated bifurcation stents may improve outcomes but need low profiles, ease of use, and cost effectiveness.
This document summarizes recent evidence on medical treatments, percutaneous coronary intervention (PCI), and coronary artery bypass grafting (CABG) for stable coronary artery disease. Key findings include:
1) Large clinical trials found no significant difference in outcomes between PCI and optimal medical therapy for stable CAD patients.
2) CABG was shown to reduce mortality, myocardial infarction, and repeat revascularization compared to medical therapy or PCI for multi-vessel disease.
3) For left main coronary artery disease, CABG may be preferable to PCI for patients with high anatomical complexity scores.
4) Ongoing trials like ISCHEMIA are further evaluating optimal revascularization strategies for stable CAD patients with ischemia.
Management strategy in HF with ARNI - Recent updates Praveen Nagula
- The document discusses management strategies for heart failure with reduced ejection fraction (HFrEF), including recent updates.
- It summarizes key differences between Indian and Western HF patients, noting that Indians develop HF at a younger age and with lower ejection fractions. Prognosis is also worse for Indian patients compared to those in the West.
- Core therapies for HFrEF are discussed, including a paradigm shift with the approval of sacubitril-valsartan which has been shown to reduce cardiovascular death compared to ACE inhibitors or ARBs alone in clinical trials.
Pci or throm or pi in stemi best strategy(apicon 09022019)-finalDr.Vinod Sharma
- Primary angioplasty, thrombolysis, and pharmaco-invasive therapy are strategies for reperfusion in STEMI patients.
- The optimal strategy depends on factors like time since symptom onset, mortality risk from STEMI, availability of a skilled PCI laboratory, and time required for transport.
- Minimizing total ischemic time is critical as myocardial necrosis increases significantly past 40 minutes from occlusion. Every 30 minute delay in reperfusion increases 1-year mortality by 8%.
Mechanical thrombectomy is a minimally invasive procedure to remove blood clots from large brain vessels. It involves inserting a catheter through a small groin incision and using stent-like devices to remove clots causing acute ischemic strokes from large artery occlusion. It can benefit patients who are not candidates for or failed intravenous thrombolysis, especially if performed within 24 hours of symptom onset. Recovery depends on patient factors but may take weeks, with potential for improved outcomes over intravenous thrombolysis alone.
The TREAT trial compared ticagrelor to clopidogrel in patients who received fibrinolytic therapy for ST-elevation myocardial infarction (STEMI). The trial aimed to evaluate the safety of ticagrelor in this setting given concerns about bleeding risk. The primary safety outcome was major bleeding at 30 days, with major efficacy outcomes including death from cardiovascular causes, myocardial infarction or stroke. The trial found ticagrelor to be non-inferior to clopidogrel for major bleeding at 30 days. Rates of other bleeding outcomes and major cardiovascular events were also similar between the two treatments.
Fibrinolytic treatment of acute myocardial infarction by tenecteplasedesktoppc
Tenecteplase is a fibrin-specific thrombolytic agent used to treat ST-elevation myocardial infarction. It is a modified form of tissue plasminogen activator (tPA) developed to have a longer half-life than other tPAs. Tenecteplase works by activating fibrin-bound plasminogen to plasmin, specifically dissolving blood clots containing fibrin. It is administered as a single intravenous bolus within 10 minutes of diagnosis of a STEMI. Guidelines recommend tenecteplase or other fibrin-specific agents for reperfusion when primary PCI is not available within 120 minutes.
Troponin elevation does not always indicate acute coronary syndrome. Troponins exist in structural and cytosolic forms in cardiac myocytes and are released upon cell injury. While elevated troponins often signal heart attacks, they can also occur due to other cardiac and non-cardiac conditions involving myocardial stress or damage, such as heart failure, pulmonary embolism, sepsis, renal failure, and strenuous exercise. The degree of troponin increase and presence of dynamic changes provide clues to determining the underlying cause of cardiac injury.
This document discusses antiplatelet therapy for acute coronary syndromes. It provides information on dual antiplatelet therapy using aspirin and P2Y12 inhibitors like clopidogrel, prasugrel, and ticagrelor. It summarizes trials comparing these drugs and outlines treatment strategies and duration of dual antiplatelet therapy based on a patient's risk level. Factors influencing response to clopidogrel and the potential additional mechanisms of action of ticagrelor are also reviewed.
Ventricular tachycardia are difficult to understand. it is classified in to two types. 1. VT in structurally normal heart, 2. VT in heart with structural diseases. I have tried to simplify the VT in structurally normal heart, which may be helpful to many students and learners.
Cardiac biomarkers provide information about heart damage and heart failure. Commonly used cardiac biomarkers include creatine kinase-MB (CK-MB), myoglobin, cardiac troponins, and natriuretic peptides.
CK-MB and myoglobin levels begin to rise earlier than cardiac troponins after a heart attack, but they are less specific to the heart. Cardiac troponins are now the gold standard biomarkers for detecting myocardial injury since they remain elevated for longer and are highly specific to the heart.
Natriuretic peptides indicate heart failure and volume overload of the heart. Together, cardiac biomarkers can provide information about myocardial injury, ischemia, heart failure, and prognosis when clinical assessment is inconclusive
Cardiac biomarkers are indicators used to objectively measure and evaluate normal biological processes, responses to treatment, and pathogenic processes in the heart. They have numerous advantages over traditional diagnostic tests as they are standardized, sensitive, specific, reproducible, and easy to interpret. This document discusses several cardiac biomarkers including C-reactive protein, soluble CD40 ligand, homocysteine, pregnancy-associated plasma protein A, lipoprotein-associated phospholipase A2, ischemia modified albumin, heart-type fatty acid binding protein, cardiac troponins, and creatine kinase. It provides details on what each biomarker indicates, their clinical uses, limitations, normal ranges, and timing of elevation following cardiac events.
Cardiac biomarkers are proteins released when heart muscle is damaged and can help diagnose and manage cardiovascular diseases. Commonly used biomarkers include cardiac troponins and natriuretic peptides. Troponins indicate heart muscle injury while natriuretic peptides reflect heart failure. High sensitivity troponin assays can detect very low levels and aid early diagnosis of heart attacks. Emerging biomarkers of inflammation like interleukin-6 may also provide prognostic information. Biomarkers are detected at different times after injury and combining their measurements over time can improve the assessment of patients with suspected cardiovascular issues.
Primary PCI involves performing urgent angioplasty and potentially stenting of the culprit artery in STEMI patients, with the goal of reopening the blocked vessel within 90 minutes of first medical contact. It is the preferred reperfusion strategy when it can be performed promptly by an experienced team. Factors such as patient age, time to treatment, comorbidities, and initial flow in the artery help determine whether primary PCI or thrombolysis is most appropriate. Optimal anticoagulation and antiplatelet regimens along with adjunctive therapies like manual thrombectomy can improve outcomes of primary PCI.
The CAPRIE study found that clopidogrel therapy resulted in a relative risk reduction of 8.7% compared to aspirin therapy for preventing cardiovascular events in patients with atherosclerosis, with fewer gastrointestinal hemorrhages. The CURE trial found that in patients with acute coronary syndrome receiving aspirin, pretreatment with clopidogrel followed by long-term therapy reduced major cardiovascular events compared to placebo. The CLASSICS trial found that clopidogrel had superior safety and tolerability to ticlopidine for antiplatelet therapy after coronary stenting, with comparable efficacy.
STEMI Late Presentation - Management and practical approachSatyam Rajvanshi
1) Late presenters of STEMI (over 12 hours) make up a significant portion of STEMI patients worldwide and in India.
2) Evidence suggests that while reperfusion therapy is not beneficial for late presenters, PCI may still allow for myocardial salvage even in occluded arteries up to 72 hours from symptom onset.
3) Guidelines vary in their recommendations for revascularization of late presenters but a practical approach is to consider early revascularization for stable patients within 72 hours while stress testing those presenting after 72 hours.
The document discusses various biomarkers used in the diagnosis and management of heart failure. It states that natriuretic peptides like BNP and NT-proBNP are the most widely used biomarkers for heart failure as they are accurate for establishing diagnosis, determining severity, and predicting prognosis. It describes the release and function of these peptides. It also mentions other biomarkers like cardiac troponins, inflammatory markers, neurohormonal factors, and matrix proteins that provide additional information on myocardial injury, inflammation, neurohormonal activation, and remodeling in heart failure. A multimarker approach may help better classify and risk stratify heart failure.
Acute Coronary Syndrome (ACS) refers to a spectrum of clinical presentations caused by acute coronary athero-thrombosis that obstruct myocardial blood flow. This includes ST-segment elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), and unstable angina. NSTEMI is diagnosed with elevated cardiac biomarkers and detected ischemia on electrocardiograms or stress tests. Treatment involves antithrombotic and anti-ischemic drugs to reduce ischemia and prevent clots. In some cases, coronary angiography and revascularization by percutaneous coronary intervention may be recommended.
Coronary bifurcation lesions are challenging to treat percutaneously and account for approximately 15% of PCIs. Interventions on bifurcations have lower success rates and higher complication rates than other lesions. The optimal strategy for treating bifurcations, whether provisional stenting of the main vessel with treatment of the side branch only if needed versus systematic two-stent techniques, is still debated. Several randomized trials have compared different approaches but longer-term data is still needed. Dedicated bifurcation stents may improve outcomes but need low profiles, ease of use, and cost effectiveness.
This document summarizes recent evidence on medical treatments, percutaneous coronary intervention (PCI), and coronary artery bypass grafting (CABG) for stable coronary artery disease. Key findings include:
1) Large clinical trials found no significant difference in outcomes between PCI and optimal medical therapy for stable CAD patients.
2) CABG was shown to reduce mortality, myocardial infarction, and repeat revascularization compared to medical therapy or PCI for multi-vessel disease.
3) For left main coronary artery disease, CABG may be preferable to PCI for patients with high anatomical complexity scores.
4) Ongoing trials like ISCHEMIA are further evaluating optimal revascularization strategies for stable CAD patients with ischemia.
Management strategy in HF with ARNI - Recent updates Praveen Nagula
- The document discusses management strategies for heart failure with reduced ejection fraction (HFrEF), including recent updates.
- It summarizes key differences between Indian and Western HF patients, noting that Indians develop HF at a younger age and with lower ejection fractions. Prognosis is also worse for Indian patients compared to those in the West.
- Core therapies for HFrEF are discussed, including a paradigm shift with the approval of sacubitril-valsartan which has been shown to reduce cardiovascular death compared to ACE inhibitors or ARBs alone in clinical trials.
Pci or throm or pi in stemi best strategy(apicon 09022019)-finalDr.Vinod Sharma
- Primary angioplasty, thrombolysis, and pharmaco-invasive therapy are strategies for reperfusion in STEMI patients.
- The optimal strategy depends on factors like time since symptom onset, mortality risk from STEMI, availability of a skilled PCI laboratory, and time required for transport.
- Minimizing total ischemic time is critical as myocardial necrosis increases significantly past 40 minutes from occlusion. Every 30 minute delay in reperfusion increases 1-year mortality by 8%.
Mechanical thrombectomy is a minimally invasive procedure to remove blood clots from large brain vessels. It involves inserting a catheter through a small groin incision and using stent-like devices to remove clots causing acute ischemic strokes from large artery occlusion. It can benefit patients who are not candidates for or failed intravenous thrombolysis, especially if performed within 24 hours of symptom onset. Recovery depends on patient factors but may take weeks, with potential for improved outcomes over intravenous thrombolysis alone.
The TREAT trial compared ticagrelor to clopidogrel in patients who received fibrinolytic therapy for ST-elevation myocardial infarction (STEMI). The trial aimed to evaluate the safety of ticagrelor in this setting given concerns about bleeding risk. The primary safety outcome was major bleeding at 30 days, with major efficacy outcomes including death from cardiovascular causes, myocardial infarction or stroke. The trial found ticagrelor to be non-inferior to clopidogrel for major bleeding at 30 days. Rates of other bleeding outcomes and major cardiovascular events were also similar between the two treatments.
Fibrinolytic treatment of acute myocardial infarction by tenecteplasedesktoppc
Tenecteplase is a fibrin-specific thrombolytic agent used to treat ST-elevation myocardial infarction. It is a modified form of tissue plasminogen activator (tPA) developed to have a longer half-life than other tPAs. Tenecteplase works by activating fibrin-bound plasminogen to plasmin, specifically dissolving blood clots containing fibrin. It is administered as a single intravenous bolus within 10 minutes of diagnosis of a STEMI. Guidelines recommend tenecteplase or other fibrin-specific agents for reperfusion when primary PCI is not available within 120 minutes.
Troponin elevation does not always indicate acute coronary syndrome. Troponins exist in structural and cytosolic forms in cardiac myocytes and are released upon cell injury. While elevated troponins often signal heart attacks, they can also occur due to other cardiac and non-cardiac conditions involving myocardial stress or damage, such as heart failure, pulmonary embolism, sepsis, renal failure, and strenuous exercise. The degree of troponin increase and presence of dynamic changes provide clues to determining the underlying cause of cardiac injury.
This document discusses antiplatelet therapy for acute coronary syndromes. It provides information on dual antiplatelet therapy using aspirin and P2Y12 inhibitors like clopidogrel, prasugrel, and ticagrelor. It summarizes trials comparing these drugs and outlines treatment strategies and duration of dual antiplatelet therapy based on a patient's risk level. Factors influencing response to clopidogrel and the potential additional mechanisms of action of ticagrelor are also reviewed.
Ventricular tachycardia are difficult to understand. it is classified in to two types. 1. VT in structurally normal heart, 2. VT in heart with structural diseases. I have tried to simplify the VT in structurally normal heart, which may be helpful to many students and learners.
Cardiac biomarkers provide information about heart damage and heart failure. Commonly used cardiac biomarkers include creatine kinase-MB (CK-MB), myoglobin, cardiac troponins, and natriuretic peptides.
CK-MB and myoglobin levels begin to rise earlier than cardiac troponins after a heart attack, but they are less specific to the heart. Cardiac troponins are now the gold standard biomarkers for detecting myocardial injury since they remain elevated for longer and are highly specific to the heart.
Natriuretic peptides indicate heart failure and volume overload of the heart. Together, cardiac biomarkers can provide information about myocardial injury, ischemia, heart failure, and prognosis when clinical assessment is inconclusive
Cardiac biomarkers are indicators used to objectively measure and evaluate normal biological processes, responses to treatment, and pathogenic processes in the heart. They have numerous advantages over traditional diagnostic tests as they are standardized, sensitive, specific, reproducible, and easy to interpret. This document discusses several cardiac biomarkers including C-reactive protein, soluble CD40 ligand, homocysteine, pregnancy-associated plasma protein A, lipoprotein-associated phospholipase A2, ischemia modified albumin, heart-type fatty acid binding protein, cardiac troponins, and creatine kinase. It provides details on what each biomarker indicates, their clinical uses, limitations, normal ranges, and timing of elevation following cardiac events.
This document discusses cardiac biomarkers used in the diagnosis and management of heart disease. It begins by introducing the members of a committee on cardiac biomarkers and providing definitions. It then discusses various biomarkers including creatine kinase-MB, myoglobin, cardiac troponins, B-type natriuretic peptide, and others. For each biomarker, it outlines their characteristics such as time of release, specificity, and clinical applications. It concludes by discussing the use of biomarkers in veterinary medicine to differentiate cardiac from non-cardiac causes of dyspnea.
This document discusses various diagnostic tests used in electrocardiography. It describes the placement of the 12 precordial leads on the chest and the 3 limb leads used in ECG. It also discusses Holter monitoring, stress testing, echocardiography including M-mode, 2D and Doppler echocardiography. Laboratory investigations discussed include cardiac markers like CK-MB, troponins and LDH along with serum lipids. Invasive hemodynamic monitoring techniques are also summarized including central venous pressure monitoring, intra-arterial blood pressure monitoring and pulmonary artery catheterization.
The things nobody told you about troponinRick Body
My talk at #RCEM15 in Manchester. What is a high sensitivity troponin assay? How can they help us? Can we use point of care troponins in our practice? Pointers for practice for those working in Emergency Medicine.
How much does it cost to launch and commercialize a companion diagnostic test?Diaceutics Group
We ask four senior executives to come up with a value on how much it would cost to launch and commercialize a novel diagnostic test. View the infographic to see what they came up with.
We defined low end as a follow on diagnostic product where a similar test exists in the market and a high end test which is a new biomarker (needing to establish novel clinical utility), or a new platform likely to be in oncology, a chronic disease like rheumatoid arthritis or a range of infectious markers requiring panel performance.
Source http://www.diaceutics.com/mystery-solved-what-cost-develop-and-launch-diagnostic#sthash.ryk5zoEa.dpuf
Louise Cullen and Rick Body fuel a contentious debate on the clinical significance of the high sensitivity troponin assay. Will your patients benefit from that extra digit ?
Cardiac biomarkers such as BNP and NT-proBNP are useful for diagnosing and monitoring heart failure. The document discusses several studies that found BNP-guided treatment of heart failure reduced mortality rates compared to symptom-guided treatment. Measurement of BNP levels can aid clinical decision making in both acute and ambulatory heart failure patients. While useful, biomarkers have limitations and should be interpreted in the clinical context of each patient.
Acs – new biomarkers & role of newer anticoagulantsArindam Pande
This document discusses biomarkers for acute coronary syndrome (ACS) and the role of newer anticoagulants. It summarizes that no single biomarker exists for ACS and that a multimarker approach is better. It describes several traditional and newer biomarkers for various pathophysiological aspects of ACS including inflammation, plaque rupture, ischemia, and myocardial injury. It also notes that while anticoagulation therapy for ACS has increased in efficacy over time, it has also increased bleeding risks. Newer anticoagulants may provide an opportunity to further reduce thrombotic risks while maintaining an acceptable bleeding profile.
This document summarizes guidelines for cardiac investigation and management of heart failure. It addresses:
- When to assess for coronary artery disease in heart failure patients
- Indications for endomyocardial biopsy and BNP testing
- Use of echocardiography and stress testing to evaluate patients
- Screening for rare diseases and comorbidities
- Use of cardiac resynchronization therapy and implantable cardioverter-defibrillators in heart failure
The document provides guidance on the appropriate use of diagnostic tests and treatments based on a patient's symptoms, ejection fraction, QRS duration, and response to medical therapy.
Louise Cullen and Rick Body fuel a contentious debate on the clinical significance of the high sensitivity troponin assay. Will your patients benefit from that extra digit ?
hFABP (heart-type fatty acid-binding protein) is an early marker of myocardial injury that can be detected in the blood within 3 hours of the onset of a heart attack. Due to its small size, hFABP leaks quickly from damaged heart cells into the bloodstream. hFABP is more specific to cardiac muscle than other early markers like myoglobin and can allow for earlier diagnosis and treatment compared to later markers like cardiac troponins. While hFABP testing has high sensitivity, false positives can occur due to skeletal muscle damage or renal failure, so clinical evaluation is also important in diagnosis.
1) The document discusses indications and complications of blood and blood product transfusions in intensive care units. It reviews evidence from clinical trials on appropriate transfusion thresholds for red blood cells, plasma, and platelets.
2) A landmark trial found a restrictive red blood cell transfusion strategy (maintaining hemoglobin between 7-9 g/dL) was as safe as a liberal strategy (10-12 g/dL) in critically ill patients, except in certain subgroups.
3) Evidence does not show consistent benefits of prophylactic or therapeutic plasma transfusion across many clinical settings and indications. Platelet transfusion is indicated at thresholds of 10-50 x 103 platelets/mL depending on bleeding risk.
This document provides information on various cardiac markers and enzymes used to detect acute myocardial infarction (AMI). It discusses creatine kinase (CK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), myoglobin, cardiac troponins, and other enzymes. It describes the tissue distribution, isoenzymes, levels in AMI, and clinical uses of CK, LDH, and cardiac troponins. It also summarizes information on other enzymes involved in AMI detection such as phosphatases, aminotransferases, and amylase.
Recent advances in the role of Cardiac bio-markers for clinical practicesubramaniam sethupathy
This document discusses various cardiac biomarkers used in the diagnosis and management of acute coronary syndrome (ACS) and myocardial infarction (MI). It provides information on biomarkers such as creatine kinase (CK), CK-MB isoenzyme, cardiac troponins, myoglobin, and others. It describes the timing of elevation, specificity, and clinical utility of each biomarker as well as situations where they may be falsely elevated or chronically elevated in conditions like heart failure or renal disease. Newer emerging biomarkers are also mentioned.
Cardiac Biomarker past, today and future by Dr. Anurag YadavDr Anurag Yadav
Cardiac biomarkers provide information about cardiac conditions by detecting substances released when the heart muscle is damaged. Over time, newer biomarkers like cardiac troponins (cTnT and cTnI) and myoglobin have improved on older markers like CK-MB for diagnosing myocardial infarction. Biomarkers are classified based on whether they indicate injury, ischemia, stress, inflammation, or prognosis. Their levels rise and fall at different rates, allowing physicians to determine the timing and extent of cardiac events. Beyond diagnostics, certain biomarkers like CRP, homocysteine, and miRNAs may directly influence cardiovascular risk and pathogenesis.
This document discusses cardiac markers that can indicate myocardial infarction (MI). It outlines several markers including troponin, creatine kinase-MB (CK-MB), myoglobin, and lactate dehydrogenase that rise at different time points after an MI. Troponin levels rise within 3 hours and remain elevated for up to 7 days, while myoglobin levels increase within 1 hour and return to normal within 24-36 hours. The document also describes methods of detecting these markers and future detection methods involving electrochemical immunosensors and implantable magnetic relaxation sensors.
This document provides an overview of myocardial infarction (MI), including its definition, types, risk factors, symptoms, diagnostic tests, treatments, and prognosis. Some key points:
- MI occurs when an area of heart muscle is permanently damaged due to prolonged lack of oxygen supply from a blockage in one of the coronary arteries.
- Risk factors include age, sex, family history, stress, obesity, smoking, diabetes, hypertension, high cholesterol, and physical inactivity.
- Symptoms can include chest pain or discomfort, shortness of breath, fatigue, sweating, and nausea. Diagnostic tests include ECG, cardiac enzymes, angiography, echocardiogram, CT scan, and nuclear stress test.
This document discusses cardiac biomarkers, specifically cardiac troponins. It begins by defining biomarkers and different types of biomarkers such as surrogate endpoints and clinical endpoints. It then discusses the history of cardiac biomarkers, including the discovery and use of CK, CK-MB, myoglobin, and troponins. Troponins T and I are now the preferred biomarkers for detecting myocardial injury as they are highly specific and their elevation persists for longer than other markers. High-sensitivity troponin assays can detect even lower levels of troponin and allow for more rapid diagnosis of myocardial infarction. Interpretation of troponin levels is more complex in patients with chronic kidney disease or after procedures like CABG.
This document summarizes research combining targeted inhibition of both BCR-ABL1 and STAT3 to induce synthetic lethality in therapy-resistant chronic myeloid leukemia (CML). The researchers discovered BP-5-087, a potent and selective inhibitor of the STAT3 SH2 domain that reduces STAT3 phosphorylation and activity. Computational modeling, biochemical assays, and testing on patient samples demonstrate that BP-5-087 directly binds STAT3. BP-5-087 restored sensitivity to tyrosine kinase inhibitors in imatinib-resistant CML progenitor cells and leukemic stem cells by inhibiting STAT3, which is activated in BCR-ABL1 kinase-independent resistance. These findings suggest dual inhibition of BCR-
High-Risk Multiple Myeloma: Distinguishing Early Failures from Sustained Controluams
This study analyzed patients with high-risk multiple myeloma to distinguish between early failures (EF) and sustained control (SC). EF was characterized by higher risk scores on the 70-gene model, lower deletion of the TP53 gene, and expression of genes associated with worse outcome like TP53INP1. In contrast, SC had overexpression of TP53INP1 linked to better survival. Further analysis of 14 genes found TP53INP1 was particularly important, with overexpression associated with SC through induction of apoptosis. Drugs like melphalan and bortezemib were also found to rapidly induce TP53INP1 in patients with low baseline levels.
1. The study aims to identify genomic and proteomic risk and protective factors for coronary heart disease by analyzing gene and protein expression profiles in blood cells from patients with and without heart disease and associated risk factors.
2. Blood samples will be collected from five patient groups and mRNA will be isolated from monocytes and neutrophils for analysis using DNA microarrays and suppression subtractive hybridization.
3. Differentially expressed genes will be confirmed with real-time PCR and protein expression analyzed using in situ hybridization and immunochemistry to help identify new diagnostic and therapeutic targets for coronary heart disease.
508 search for genomic and proteomic risk factors and protective factors asso...SHAPE Society
1. This study aims to identify genomic and proteomic risk factors and protective factors associated with coronary heart disease by analyzing gene and protein expression profiles in blood cells from patients with and without heart disease.
2. The study will recruit patients aged 18-80 categorized into five groups based on having heart disease and traditional risk factors. Gene expression in monocytes and neutrophils will be analyzed using microarray technology and real-time PCR.
3. Differentially expressed genes will be identified by comparing expression profiles between patient groups to uncover new diagnostic markers and therapeutic targets for coronary heart disease.
Acute myeloid leukemia is a cancer of the myeloid line of blood cells, characterized by increased numbers of immature myeloid cells in the bone marrow. Dysregulated cell differentiation, uncontrolled growth, and inhibited apoptosis contribute to disease progression. Managing AML in India is challenging, as the median age of patients is 40 years. AML results from mutations that activate proliferation and survival signaling pathways like JAK-STAT, Ras-Raf-MEK-ERK, PI3K-Akt-mTOR, and inhibit apoptosis. Novel therapeutic approaches target deregulated pathways like CREB and anti-apoptotic proteins to overcome treatment resistance.
This document provides an overview of chronic myeloid leukemia (CML), including:
- CML is characterized by the Philadelphia chromosome and BCR-ABL1 fusion gene. It has three phases: chronic, accelerated, and blast.
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The Past, Present, and Future of Cardiac Biomarkers
1. The Past, Present, and
Future of Cardiac
Biomarkers
Presented By: Curtis Beebe, B.S., Medical Laboratory Science Intern
Heritage University
2. OBJECTIVES
AT THE END OF THIS PRESENTATION THE LEARNER WILL BE ABLE TO:
1. EXPLAIN WHETHER TESTING FOR CARDIAC BIOMARKERS IS WARRANTED OR NOT
BASED ON CLINICAL SYMPTOMS USING TWO JUSTIFIABLE REASONS.
2. NAME ONE UNIQUE ADVANTAGE OR DISADVANTAGE FOR FIVE OF THE CARDIAC
BIOMARKERS PRESENTED WITH 80% ACCURACY.
3. PREDICT WHETHER RESULTS WILL BE INCREASED OR DECREASED FOR FIVE OF THE
CARDIAC BIOMARKERS THAT WERE PRESENTED BASED ON CLINICAL SYMPTOMS.
4. WHAT IS A BIOMARKER?
BIOLOGICAL MOLECULE THAT IS MEASURABLE
CELLS
PROTEINS
GENES
HORMONES
MANY ARE CLINICALLY USEFUL AND THEY ENCOMPASS A MYRIAD OF DIFFERENT
BIOLOGICAL PROCESSES
5. WHY DO THE VALUES CHANGE IN CELL DAMAGE?
ANAEROBIC RESPIRATION
INHIBITION OF MEMBRANE TRANSPORT
ELECTROLYTE IMBALANCE
LYSOSOMAL ENZYMES
MEMBRANE INTEGRITY
6. WHAT CAN CARDIAC BIOMARKERS REVEAL?
CONGESTIVE HEART FAILURE
(CHF)
A CONDITION IN WHICH THE
HEART IS UNABLE TO PROVIDE
SUFFICIENT BLOOD FLOW TO THE
BODY
ACUTE CORONARY SYNDROME
(ACS)
ENCOMPASSES CONDITIONS IN
WHICH THE HEART CAN NOT
FUNCTION PROPERLY OR DIES
7. WHY DO THEY MATTER?
RISK ASSESSMENT/PREVENTION
DIAGNOSIS
THERAPY
PROGNOSIS
ABOUT 1/3 OF DEATHS IN THE WORLD ARE DUE TO CARDIOVASCULAR
DISEASE, OF WHICH A GREAT PROPORTION IS CORONARY ARTERY DISEASE
15% DIRECTLY DUE TO AMI
8. WHAT TRAITS ARE NEEDED?
HIGH SENSITIVITY
HIGH CONCENTRATION IN MYOCARDIUM AFTER
MYOCARDIAL INJURY
RAPID RELEASE FOR EARLY DIAGNOSIS
LONG HALF-LIFE IN BLOOD FOR LATE DIAGNOSIS
HIGH SPECIFICITY
ABSENT IN NON-MYOCARDIAL TISSUES
NOT DETECTABLE IN BLOOD OF NON-DISEASED
SUBJECTS
ANALYTICAL CHARACTERISTICS
MEASURABLE BY COST-EFFECTIVE ASSAY
SIMPLE TO PERFORM
RAPID TURNAROUND TIME
SUFFICIENT PRECISION AND TRUENESS
CLINICAL CHARACTERISTICS
ABILITY TO INFLUENCE THERAPY
ABILITY TO IMPROVE PATIENT OUTCOME
9. WHO DIAGNOSTIC CRITERIA FOR AMI
CURRENTLY IN THE 3RD GENERATION
REQUIRES RISING AND FALLING LEVELS OF CARDIAC TROPONINS
“MYOCARDIAL CELL DEATH DUE TO PROLONGED ISCHEMIA”
DIAGNOSIS TODAY REQUIRES A RISE AND/OR FALL OF BIOMARKER VALUES (PREFERABLY
TROPONIN) WITH ONE VALUE ABOVE THE 99TH PERCENTILE
THE RISE/FALL PATTERN DISTINGUISHES BETWEEN ACUTE AND CHRONIC DISORDERS
12. PATHOLOGICAL DEFINITION
CLASSIFIED AS ACUTE, HEALING, OR HEALED
ACUTE-PRESENCE OF PMNS
HEALING-PRESENCE OF MONONUCLEAR AND FIBROBLAST CELLS, NO PMNS
HEALED-SCAR TISSUE WITH NO CELLULAR PRESENCE
ACUTE STAGE TO HEALED STAGE TYPICALLY REQUIRES 5-6 WEEKS
13. QUESTION 1
TRUE OR FALSE: A RISE AND/OR FALL PATTERN
WITH AT LEAST ONE VALUE ABOVE THE 99TH
PERCENTILE UPPER REFERENCE LIMIT OF CARDIAC
TROPONINS IS DIAGNOSTIC FOR MI ACCORDING TO
THE WHO CRITERIA.
FALSE. THIS IS ONE REQUIREMENT, BUT THE WHO ALSO
REQUIRES ONE OF THE FOLLOWING FOR DIAGNOSIS:
1) SYMPTOMS OF ISCHEMIA
2) NEW OR PRESUMED NEW SIGNIFICANT CHANGES IN THE
ST-T WAVE SEGMENT
3) EVIDENCE OF THROMBUS VIA ANGIOGRAPHY
4) IMAGING EVIDENCE OF NEW LOSS OF VIABLE
MYOCARDIUM OR REGIONAL WALL MOTION ABNORMALITY
5) ST-T WAVE CHANGES CONSISTENT WITH MI
14. THE TASK AT HAND
DIFFERENT BIOMARKERS ARE ELEVATED IN DIFFERENT CLINICAL SITUATIONS
15. THERE’S A LONG HISTORY
ASPARTATE AMINOTRANSFERASE IN LATE 1950’S
CREATINE KINASE IN 1960’S
LACTATE DEHYDROGENASE LD1 IN 1970’S
CREATINE KINASE MB-FRACTION IN 1972
16. CREATINE KINASE (1960’S)
MYOCARDIUM CONTAINS A SPECIFIC AMOUNT
INCREASES WITHIN 4-8 HOURS AFTER MI
PEAKS AT 18-24 HOURS
BASELINE AFTER 48-72 HOURS
17. LACTATE DEHYDROGENASE LD1 (1970’S)
DETECTS CARDIAC DAMAGE LONG AFTER MI
APPEARS IN 4-6 HOURS, REMAINS ELEVATED FOR 4-14 DAYS
NOT SPECIFIC FOR CARDIAC MYOCYTES
INCREASED IN: LEUKEMIA, ANEMIA, MYOGLOBINURIA, MUSCULAR
DYSTROPHY, RENAL DISEASE, CARCINOMA
18. CK-MB (1970’s)
CAN DETECT REINFARCTION BETWEEN 3-10 DAYS OF FIRST EPISODE
SERUM LEVELS ARE BASELINE BY 72 HOURS
SENSITIVITY ONLY 50% AT 3 HOURS AND 80% AT 8 HOURS
LIMITED BY INCOMPLETE SPECIFICITY
STILL VALUED FOR REINFARCTION AND UAP
19. QUESTION 2
RELATIVE TO CK-MB, ONE OF THE MAIN
REASONS LACTATE DEHYDROGENASE WAS
USEFUL AS A CARDIAC BIOMARKER WAS:
A. THEY WERE DETECTABLE IN DIAGNOSTIC
CONCENTRATIONS SOONER
B. THEY REMAINED ELEVATED FOR AN EXTENDED
PERIOD OF TIME
C. THEY WERE HIGHLY SPECIFIC FOR CARDIAC
MYOCYTE DAMAGE
20. WHAT MARKERS ARE TESTED FOR TODAY
CARDIAC TROPONINS
BRAIN-TYPE NATRIURETIC PEPTIDE
NT-PROBNP
21. THE TROPONIN COMPLEX
TROPONIN COMPLEX CONSISTS OF CTNT, CTNI,
AND CTNC
ONLY CTNI AND CTNT ARE TESTED IN THE LAB
ENCODED BY DIFFERENT GENES
BOTH ARE PRESENT IN STRIATED CONTRACTILE
APPARATUS AND CYTOSOL
THE CYTOSOLIC CONCENTRATION OF EACH
ISOFORM DIFFERS
22. CARDIAC TROPONINS
CTNT AND CTNI
SERVE AS THE STANDARD FOR DIAGNOSIS OF MI
PER EUROPEAN SOCIETY OF CARDIOLOGY & AMERICAN COLLEGE OF CARDIOLOGY
DETECTABLE FOR A LONGER TIME
APPEAR 3-4 HOURS AFTER MI
PEAK 12-48 HOURS AFTER
ABNORMAL FOR 7-14 DAYS
INDICATE MYOCARDIAL NECROSIS
23. HS-TROPONIN
INCREASE IN FALSE-POSITIVES
TROPONINS STILL WON’T BE DETECTED IMMEDIATELY FOLLOWING ISCHEMIA
STILL EARLIER DETECTION OF MI COMPARED TO CURRENT METHODS
AS EARLY AS MYOGLOBIN CAN BE DETECTED
24. IS THERE ALWAYS A HEART PROBLEM WITH INCREASED CTN?
RENAL ISSUES
CHRONIC KIDNEY DISEASE (CKD)
AFFECTS 15% OF THE US
25. BNP
INCREASED IN CONGESTIVE HEART FAILURE
RELEASED DUE TO BIOMECHANICAL STRESS
BRAIN-TYPE NATRIURETIC PEPTIDE
<100 NG/L: HF IS HIGHLY UNLIKELY (NPV 90%)
>500 NG/L: HF IS HIGHLY LIKELY (PPV 90%)
26. NT-PROBNP
THE N-TERMINAL END OF THE INACTIVE PROHORMONE BNP
STUDIES HAVE SHOWN
<300 NG/L: HF HIGHLY UNLIKELY (NPV 99%)
>450 NG/L IN PATIENTS UNDER 50: HF IS HIGHLY LIKELY
>900 NG/L IN PATIENTS OVER 50: HF IS HIGHLY LIKELY
HIGH PROGNOSTIC VALUE
27. NT-PROBNP OR BNP?
BNP IS A SUPERIOR MARKER
BOTH HAVE DECREASED PERFORMANCE WITH INCREASING PATIENT AGE AND
SEX (MORESO WITH NT-PROBNP)
28. ACTIVITY
GET INTO GROUPS OF 2-3 PEOPLE
CHOOSE 3 OF THE FOLLOWING AND WRITE
DOWN AS MANY ADVANTAGES OR
DISADVANTAGES AS YOU CAN FOR EACH, THEN
WE’LL SHARE
1. LACTATE DEHYDROGENASE
2. CREATINE KINASE
3. CREATINE KINASE MB FRACTION
4. TROPONINS
5. BNP
6. NT-PROBNP
7. HIGH-SENSITIVITY TROPONIN TESTING
29. WHAT’S NEXT?
HEART-TYPE FATTY ACID BINDING PROTEIN (H-FABP)
GLYCOGEN PHOSPHORYLASE ISOENZYME BB (GPBB)
SUPPRESSION OF TUMORIGENICITY 2 (ST2)
MICRORNA
30. HEART-TYPE FATTY ACID BINDING PROTEIN
CYTOPLASMIC PROTEIN INVOLVED IN THE UPTAKE OF FATTY ACIDS INTO
MYOCARDIUM
PRESENT IN A VERY HIGH CONCENTRATION IN MYOCARDIUM (5 MG/G TISSUE)
RELEASED DURING ISCHEMIA
HAS PROGNOSTIC VALUE
ELEVATED WITHIN 2 HOURS, BASELINE 12-24 HOURS
31. GLYCOGEN PHOSPHORYLASE ISOENZYME BB
1 OF 3 ISOENZYMES AND PRODUCED IN THE BRAIN AND HEART
A STUDY OF 61 PATIENTS PRESENTING SYMPTOMS OF ACS, (37 MI, 24 UAP),
FOUND 90.1% OF PATIENTS HAD INCREASED GP-BB CONCENTRATIONS 1 HOUR
AFTER CHEST PAIN AND 100% AFTER 4-5 HOURS
AT 6 HOURS, 95.5%-100% SENSITIVITY, 94-96% SPECIFICITY
TROPONINS AT ≥3 HR: >95% SENSITIVITY, 100% SPECIFICITY
32.
33. SOLUBLE ST2: SUPPRESSION OF TUMORIGENICITY 2
A PROTEIN IN THE INTERLEUKIN FAMILY
BOTH BOUND AND SOLUBLE VERSIONS, SST2 AND ST2L
PROVIDES DATA REGARDING CHF, LIKE NT-PROBNP/BNP
PROGNOSTICALLY VALUABLE
34. WHAT IS MICRORNA?
RNA STRAND THAT IS
19-25 NUCLEOTIDES
LONG
RESPONSIBLE FOR GENE
REGULATION BY
INTERACTING WITH 3’-
UTR OF MESSENGER
RNA
FOUND IN EVERY CELL
BUT HAS ORGAN AND
CELL SPECIFIC
EXPRESSION PATTERNS
35. THE IMPORTANT ONES SO FAR
MIRNA-1: SPECIFIC FOR STEMI
MIRNA-21: FIBROBLASTS
MIRNA-28: ONLY IN CARDIOMYOCYTES
MIRNA-29: NECROSIS
MIRNA-126: REPAIR
MIRNA-133: MYOBLASTS
MIRNA-208: SPECIFIC FOR STEMI
36. WHAT WE LEARNED
ULTIMATELY THE GOAL IS TO USE MULTIPLE BIOMARKERS TO DETERMINE THE
PRESENCE, CAUSE, AND EXTENT OF DAMAGE TO CARDIAC TISSUE
LD, CK, AND CK-MB WERE USED AGES AGO BUT HAVE BEEN REPLACED BY
THE TROPONINS
TROPONINS ARE THE CURRENT STANDARD FOR DIAGNOSIS OF MYOCARDIAL
INFARCTION
GPBB, H-FABP, SST2, AND MIRNA HAVE THE POTENTIAL TO IMPROVE THE
DIAGNOSIS AND TREATMENT OF PATIENTS SUSPECTED OF AN ADVERSE
CARDIAC EVENT
38. REFERENCES
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present. Clinical Chemistry. 2004;50(11):2205–13. DOI: 10.1373/clinchem.2004.041749.
2. Dolci A, Panteghini M. The exciting story of cardiac biomarkers: from retrospective detection to gold diagnostic standard for acute myocardial
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5. Jaffe A, Babuin L, Apple F. Biomarkers in acute cardiac disease: the present and the future. Journal of the American College of Cardiology.
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6. Schulte C, Zeller T. Microrna-based diagnostics and therapy in cardiovascular disease-summing up the facts. Cardiovasc Diagn Ther. 2015 Feb;5(1):17–
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7. Viswanathan K, Kilcullen N, Morrell C, Thistlethwaite S, Sivananthan M, Hassan T, et al. Heart-type fatty acid-binding protein predicts long-term
mortality and re-infarction in consecutive patients with suspected acute coronary syndrome who are troponin-negative. J Am Coll Cardiol. 2010;55(23).
DOI: 10.1016/j.jacc.2009.12.062.
8. Thygesen K, Alpert JS. Universal definition of myocardial infarction. J Am Coll Cardiol [internet]. 2007; Available from:
http://content.onlinejacc.org/article.aspx?articleid=1138690
9. Ewald B, Ewald D, Thakkinstian A, Attia J. Meta‐analysis of b type natriuretic peptide and n‐terminal pro b natriuretic peptide in the diagnosis of
clinical heart failure and population screening for left ventricular systolic dysfunction. Intern Med J. 2008;38(2):101–13. DOI: 10.1111/j.1445-
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12. Shortt CR, Worster A, Hill SA, Kavsak PA. Comparison of hs-cTnI, hs-cTnT, hFABP and GPBB for identifying early adverse cardiac events in patients
presenting within six hours of chest pain-onset. Clin Chim Acta. 2013 Apr 4;419:39–41. DOI: 10.1016/j.cca.2013.01.008.
13. Lippi G, Mattiuzzi C, Comelli I, Cervellin G. Glycogen phosphorylase isoenzyme BB in the diagnosis of acute myocardial infarction: a meta-analysis.
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2010 Jul 4;119(2):87–95. DOI: 10.1042/CS20090645.
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society of cardiology (esc). Eur Heart J. 2012;33(20):2569–619. DOI: 10.1093/eurheartj/ehs215.
24. Peetz D, Post F, Schinzel H, Schweigert R, Schollmayer C, Steinbach K, et al. Glycogen phosphorylase bb in acute coronary syndromes. Clin
Chem Lab Med. 2005;43(12):1351–8. DOI: 10.1515/CCLM.2005.231.
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10.1007/s12265-013-9459-y.
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REFERENCES CONTINUED
41. QUIZ ANSWERS
1. False
2. BNP, NT-proBNP, sST2
3. D
4. 1-3 hours
5. Troponin-Increased
BNP-Normal
sST2-Normal
H-FABP-Increased
LD1-Increased
6. Yes because: dyspnea is a symptom of MI, NSTEMI may be present, R/O
any heart damage, could be UAP or any other acute coronary syndrome,
age.
Editor's Notes
1. A physician sees a 30 year old patient whom, upon examination, explains that he has been experiencing chest tightness, dyspnea, and always seems to be tired, especially when walking up stairs. He also says he has had a cough that won’t seem to go away. Most of these symptoms started about two weeks ago and have progressed since, but he thought he simply had a cold that would resolve itself over time. The patient states he has never smoked and follows healthy eating habits.
Anaerobic respiration: lactic acid builds up in the cell due to oxygen deprivation, pH decreases
Inhibition of membrane transport: There’s simply not enough ATP production to support ATP-dependent membrane transport
Membrane integrity:
Lysosomal enzymes: the decreased pH causes the release of proteolytic enzymes which destroy intracellular structures and cause cleavage of membrane bound proteins.
This process causes the release of both cytosolic proteins and structurally bound proteins. Cytosolic proteins are released first and are dependent on the amount of circulation to the affected area. Bound proteins are released second and their values are independent of the circulation reaching affected cells.
Congestive heart failure: heart is unable to pump sufficiently to maintain sufficient blood flow for the body. A multitude of disease states are responsible. There are two types: left-side failure and right-side failure. Both can cause pleural effusion.
Acute coronary syndrome: myocardial infarction (NSTEMI/STEMI), hemodynamic stress, inflammation, vascular damage, acute atherosclerosis, and unstable angina pectoris3
Left-side is more common and includes more pulmonary related symptoms: labored breathing, cyanosis, “rales and crackles” when breathing, pulmonary edema, wheezing, dyspnea.
Right-side includes more vascular symptoms: edema, ascites and liver enlargement.
Acute myocardial infarction: necrosis of cardiac tissue due to a blockage of blood flow, perhaps embolism, plaque, etc.
Angina: an experience of chest pain due to the narrowing of the coronary arteries.
Stable Angina Pectoris: chest pain occurring regularly due to exercise, meals, etc., that is predictable. This is the type often associated with MI
Unstable Angina Pectoris: Chest pain that occurs but isn’t regular or predictable. It changes in pain level, intensity, frequency, etc. It can precede MI but, in patients diagnosed with this, there is often no elevation of any cardiac biomarkers.
NSTEMI: Non ST-T Wave Elevation Myocardial Infarction. No elevation in the ST-T wave of an ECG
Coronary Artery Disease (CHD): part of a group of diseases including Stable Angina, Unstable Angina, MI, and sudden coronary death as a group of diseases. Coronary Artery disease is the most common of the group. Basically, it’s atherosclerosis in a coronary artery. In 2011, it was the most common cause of death globally with over 7 million deaths, accounting for 12.8% of all worldwide deaths.23 Also, about 20% of individuals over 65 have CAD. Relative to MI, the arteries are damaged not blocked.
Can anyone tell me some sort of process where the heart muscle dies?
The most debilitating manifestation of coronary artery disease is MI. This sets the precedent for the importance of finding biomarkers that are detectible sooner after the initial event, are detectible longer, and that show specificity for the type, location, and cause of the damage. Currently, there aren’t any single biomarkers, or combinations thereof, that have achieved this feat. Yet as scientists, we push forward diligently (maybe assiduously; It’s a better word but they may not know), in the hopes that serendipity is on our side.
Risk Assessment:
What physiological reasons determine a biomarkers unique characteristics?4
Location in the cell. Cytosolic molecules are released immediately following cellular damage whereas structurally bound molecules are released later.
Molecular weight. Smaller molecules diffuse faster than larger molecules.
Half-life. Smaller molecules tend to be eliminated more rapidly than larger molecules.
Relationship to blood flow. The cytosolic molecules are heavily affected by the relative difference between blood flow in the necrotic region and non- necrotic region. This difference in blood flow does not affect structurally bound molecules.
Myocardial infarction is cell necrosis due to ischemia; where ischemia is defined as an imbalance between perfusion supply and demand.8,12 Following this imbalance are various symptoms including: combinations of chest, upper extremity, jaw, or epigastric discomfort with or without exertion.8 These symptoms last at least 20 minutes and are often accompanied by dyspnea (trouble breathing), syncope (fainting), diaphoresis (sweating), or nausea.8 The symptoms are also diffuse and can easily be misdiagnosed as some other disorder unrelated to ischemia. Myocardial infarction can also be present without any noticeable symptoms, only identified by EKG, biomarkers, or imaging techniques.8,12 Interpreting clinical symptoms in order determine the correct diagnosis therefore is incredibly difficult and the heart can continue to sustain damage while the physician determines the cause. Correct diagnosis requires rapid, specific, and sensitive testing.
According to WHO, the specific pathology of myocardial infarction is “myocardial cell death due to prolonged ischemia”.8 It’s important to understand that cell death is not immediate after ischemia occurs, but takes, at minimum, 20 minutes. Complete necrosis of affected affected tissue requires 2-4 hours depending on collateral circulation.
Retrieved from “Third universal definition of myocardial infarction.” (14)
Worldwide, about 3 million are diagnosed with NSTEMI each year and 4 million with STEMI
An ECG measures the electrical activity of the heart. The P, Q, R, and S-wave reflect depolarization of the heart which means an influx of calcium ions right before the myocytes contract, first the atria (P-wave), then the ventricles (QRS-wave). Electrical activity is generated by the sinoatrial node in the atria and the atrioventricular node in the ventricles. The T-wave represents repolarization of the ventricles. Repolarization is in the negative direction since it is the opposite of depolarization but the peak is positive because the direction of repolarization is in the opposite direction as depolarization. In the way that two negatives multiplied together is a positive number.
STEMI represents complete blockage of on or more coronary arteries and is the most damaging (all affected cells will die); NSTEMI is a milder form. This is important because non-ST-wave elevation won’t be diagnosed as MI right away (the ECG may look normal), leading to increased importance on biomarkers.
There may be more than one type present in a single patient. The definition includes only necrosis due to ischemia. Necrosis due to other causes is not termed MI.8
These definitions are incredibly important because not only determining the presence or absence of MI but also the stage, prognosis, and treatment need to be determined. Remember that the clinical timing may not always correspond to the pathological timing, (i.e., there may still be clinical signs when the heart is in the healing/healed phase).
False. This is one criteria but also required is one of the following: MI consistent symptoms, or imaging of MI, or evidence of thrombus, or ST-T wave changes consistent with MI.
This figure shows the characteristic disease process that eventually ends with myocardial necrosis and dysfunction.16 Today we have markers that are highly sensitive and highly specific for heart damage (e.g., the troponins and BNP). The disconcerting fact is that this process was underway long before the damage actually occurred.16 With UAP, the defining feature is no elevation in biomarkers.
GDF-15: Growth Differentiation Factor 15
ST2
Not specific for the heart. Is found in all muscle and an increase can easily be mistaken for cardiac damage when only skeletal damage occurred. Also, dilutions make the accuracy of the test much lower in the lab.(Per Darlene)
There are 5 isoenzymes. Normally they are in a specific order from highest to lowest concentration. The heart is rich in LD1 and LD2 whereas the liver is rich in LD3, LD4, LD5.4 LD2 is also found in serum and an increased ratio of LD1/LD2 represents heart damage. Peaks at 72 hours.
Each unit (gram) of myocardium releases a specific amount of CK into circulation and the amount is related to the extent of the damage.1 However, in contrast to total CK, MB was much more specific and sensitive for cardiac damage as 25% of CK in myocytes was MB and the rest MM. This cemented its place as a much more useful marker than total CK. Detection of re-infarction wasn’t practical with LD due to its long detection period. The more rapid detection (per test methods, which were electrophoresis and immunoinhibition4, allowed medical decisions to be made sooner, patients without MI could be discharged in 1 day versus the traditional 3, and treatment could begin sooner for those with confirmed MI.
There is only one CK-MB isoform within muscle but upon release into circulation modification occurs to create two, MB1 (the modified form) and MB2 (the tissue form).4 The differentiation of MB1/MB2 however, offers no advantage to total CKMB testing.4
The answer is B. They remained elevated for 4-14 days, in contrast to the 2-3 day elevation of CK-MB.3 However, the detection window was 4-8 hours, just like CK-MB. And LD is not highly specific for cardiac damage. This trait decreased its diagnostic role as a biomarker.
Picture is from reference 11.
The TnC, TnI, and TnT complex is located on the striated muscle contractile apparatus.16 Each is encoded by a separate gene and therefore is distinguishable from the others.16 Although most of the complex is bound to striated muscle there is also a small cytosolic pool for TnI (2.8-4.1%) and TnT (6-8%).1,16 This trait leads to differences in detection, both rapidity and duration, between the two isoforms.1,16 Rapid release of the cytosolic TnT pool occurs first following ischemia. Followed by the release of the entire complex from the myofibrils.16 The larger TnT cytosolic pool leads to biphasic release kinetics whereas the TnI release kinetics are monophasic due to its smaller cytosolic pool.16
At its most basal level, the myocardium contracts when calcium concentration increases, and relaxes when the calcium concentration falls. Contractile Process: TnI blocks myosin binding sites on the actin filament; a change in action potential opens calcium ion transporters and some calcium binds TnC; this releases the TnI from the myosin binding sites; myosin binds and generates force to contract the muscle filament. (Remember that TnT binds to tropomyosin in the actin filament to anchor the complex).
Released from the cytosolic pool first due to necrosis, later released from the structural pool.5 Expressed almost exclusively from the heart as they are part of the contractile apparatus.14 They indicate myocardial necrosis but don’t reveal the underlying mechanism. Excellent specificity and sensitivity, some studies have found ****sensitivities as high as _____ and specificities as high as ______, better than all previous markers.16
Why don’t we test for both isoforms in the lab? Roche diagnostics holds a patent on the cTnT immunoassay test method so it comes down to cost.
A very important point regarding troponin is that it doesn’t discriminate between ischemic damage from non-ischemic damage. All raised troponin can provide is whether or not necrosis has occurred.4
One of the main disadvantages is that in part of the population, predominantly the elderly, have an elevated troponins due to chronic heart failure or chronic kidney disease. False-positives are always a problem with high sensitivity tests. With high-sensitivity testing it takes 2-4 hours to detect troponins after MI or some other event.6 Diagnosis of MI requires one value outside of the 99th percentile. Remember that the WHO requires the troponin rise/fall pattern as well as one other criteria to diagnose MI.
This is the biggest disadvantage to cTn.22 The troponins are also elevated in renal disease, especially End Stage Renal Disease. cTnT is more valuable in this respect, being elevated in 30-70% of patients with ESRD. cTnI is elevated in about 5% of the same patients.5 So depending on the patient cTn can be useful in diagnosing various disorders unrelated to MI. With cTnT being more useful in patients with renal disorders.
Introduced as a pro-peptide and then cleaved by the enzyme corin.5 BNP is secreted by the ventricles in response to increased cardiomyocyte stretching and ventricular pressure and it binds to receptors that cause a reduction in systemic vascular resistance, central venous pressure, and natriuresis (increase in sodium excretion will decrease the extracellular volume and pressure on the heart). Suggestive of CHF (heart can’t pump enough blood to supply the needs of the body), not necrosis.
Interestingly, some proBNP circulates regardless of cardiac damage and current tests likely detect this irrelevant amount. proBNP normal values are different depending on physiological variables (e.g., age, sex, comorbidities). Women and older individuals have higher normal values, obese have lower values. This increases the difficulty in determining if a cardiac event has actually occurred. Although when combined with cTns, the diagnostic and prognostic value can be synergistic. The caveat is values that fall in the middle ranges. proBNP can be elevated in other disorders as well including: right-sided heart failure, sepsis, volume overload, stroke, and left-ventricular hypertrophy.5
BNP is superior to NT-proBNP in the diagnosis of congestive heart failure.9 Although the age-related and sex related differences make the clinical value of BNP results more difficult to determine. In a meta-analysis regarding heart failure, BNP had a sensitivity of 85% and specificity of 84%.9
We’ll do this as a group for 5 minutes and then share answers with the rest of the group. I haven’t decided whether to use poster paper and then just have them bring up the sheets so I can present them. I think it’ll take too long to have each group explain what they wrote.
So one downside that occurs so far is the time between any cardiac event and the possibility of detecting troponins or other cardiac markers. A large amount of damage could occur in those first few hours. Also, differentiating Unstable Angina Pectoris from Non-Coronary Chest Pain can’t be done with troponin or any other current marker.6
ST2: is involved in the cardial remodeling pathway. It also helps in determining mortality and prognosis. It’s unrelated to the natriuretic peptides, and as such is able to offer additional information when coupled with the NPs.
Clinically useful in patients that are troponin negative (indicating something other than MI). Highly concentrated in the myocardium.12
Together with troponin it has a high prognostic value. Troponin negative people with increased H-FABP represent the moderate risk patients.
GPBB is an enzyme involved in cellular metabolism and dissociates from glycogen during ischemia, within the first hours of onset.12,22
For MI:
Myoglobin at 6 hours: 85-95% sensitivity22
CK-MB mass: 71.4%-91.3% sensitivity22
For UAP:
GPBB: large increase in 93.9% of patients22
Myoglobin: increased in 66.7%22
cTnT: 33.8%22
CK-MB: 55.0%22
So cTnT wasn’t very useful in diagnosing UAP but was able to determine patients who were negative for MI incredibly well.
The enzymes are GP-MM, GP-BB, and GP-LL (skeletal muscle, brain and heart, liver, respectively).22
Multiple studies have obtained similar results (e.g., reference 24).
Notice that a 3-4 fold increase in GPBB is present within 1 hour of the start of MI whereas troponin takes roughly 4-5 hours to be helpful. Also notice the lack of an increase in the early stages of MI and the continual relative increase in GPBB.
sST2 can be used in the prognosis of CHF (highly specific), similar to BNP and ANP, not for necrosis (MI).25
When used alongside NT-proBNP, more information regarding prognosis can be determined. High sST2/high NT-proBNP=worst prognosis; low sST2/high NT-proBNP=moderate; low sST2/NT-proBNP=worst prognosis; this means it provides information independent of NT-proBNP
It also provides prognostic information that is independent of traditional risk factors regarding a second cardiac event.
Not powerful enough to be used independently in the diagnosis of any disease states.
It has effects on apoptosis, inflammation, fibrosis, and remodeling. This is the reason it is useful in prognosis (i.e., it indicates state and healing process of the heart).
ST2 ligand is IL-33 which is able to inhibit hypoxia induced apoptosis, infarct volume, and fibrosis of affected tissue. IL-33 is activated by ST2L wherea sST2 acts as a decoy receptor and prevents activation.
miRNA is a short oligonucleotide that negatively (post-transcriptionally) regulates mRNA by promoting degradation or repression. Each miRNA has target sites on hundreds of genes.6 It’s estimated that over 60% of human genes are regulated by miRNA.6 Research shows that up and down regulation of cell/organ specific miRNA is altered in different fields of cardiac disease and polymorphisms in the miRNA regulation pathway are associated with certain disease states.6 Extraordinarily stable in circulating blood.6,19 Potential strategies for how to use them: construct molecules that mimic their function, construct anti-sense oligonucleotides that are extremely specific and will make targets dysfunctional, and overexpress miRNA of interest that is downregulated in specific disease processes.19
What if we could determine what kind of damage the heart endured, if heart cells are undergoing remodeling due to a cardiac event that was undetected, if tissue fibrosis is occurring, what cells were specifically damaged and what the surrounding tissue is doing about it? That’s all possible with miRNA. Unlike troponin, some miRNAs are able to enter the urine and could provide new means for cardiomyopathy detection.19
Importantly, in a study on 332 patients with suspected ACS, miRNAs were compared to hs-cTn. The researchers found that in all patients various miRNAs were upregulated, including those patients that had a negative hs-cTn.19
miRNA-1 Cells that underwent necrosis from a coronary occlusion increase expression of miR-1 (which is pro-apoptotic in cells under oxidative stress).6 Increased plasma concentration in patients with STEMI, but only a very slight increase in other cardiac dysfunction.22 This is the most abundant miRNA in the heart and is heart and muscle specific.23 In one study, there was a 60-fold increase of miRNA-1 in urine at 24 hours that returned to normal after 7 days. This was true for patients presenting with STEMI.19
miRNA-21 is upregulated shortly after ischemia but is down-regulated before cell death occurs; it’s also thought to be involved in fibroblast proliferation.6
miRNA-28 is only expressed in cardiomyocytes and released upon cell death, therefore is highly specific for cardiac events.6 The
miRNA-29 family is expressed in cells adjacent to necrotic cardiomyocytes.6
miRNA-126 is involved mainly with the reparative phase.6
miRNA-133 enhances myoblast differentiation and proliferation.6 Peak at 2h following MI.19
miRNA-208B expressed in the heart but undetectable in healthy individuals and individuals without MI. In one study, it was detected upon myocyte injury in 100% of patients within 4 hours. Troponin T was released as well, whereas Troponin I was unaffected.19 Specific for STEMI. Within 12 hours, the concentration increased 3000-fold.19 Although another study had similar findings, there wasn’t a statistical advantage over troponin T.19
miRNA changes occur with any type of cellular stress, although the specific miRNA differs for each. All that needs to be done is find the correct miRNA for the type of damage being considered.
miRNA also has the potential as a therapeutic target.
Ultimately, the goal is to use multiple biomarkers to characterize a cardiac disorder and therefore improve treatment. This can provide clinicians with the ability to tailor therapy or even prevent an adverse cardiac event from occurring in the first place.11
We also learned that the important qualities of a good indicator are: specificity, sensitivity, and analytical and clinical characteristics.