A cardiac stress test assesses a heart's response to stress and can help diagnose coronary artery disease. Dr. Arun Vasireddy's seminar discussed the types and indications for stress testing, including exercise tests and pharmacological tests. Stress tests evaluate coronary blood flow, cardiac function, and the development of ischemia through changes in EKG readings, imaging, and symptoms. Interpreting stress test results involves analyzing changes in heart rate, blood pressure, perfusion imaging, wall motion, and other metrics during rest and stress conditions. Stress echocardiography and myocardial perfusion imaging are important non-invasive tests to evaluate cardiac function and identify ischemic areas of the heart muscle.
coronary artery bypass graft surgery CABGSunil kumar
coronary artery bypass graft surgery, explanation of CABG on-pump and off-pump procedures, physiotherapy management after surgery. indications of CABG. description of the procedure, investigations before surgery, per operative and post operative management
Cardiac Rehabilitation has been defined as:
Coordinated, multifaceted interventions designed to optimize a cardiac patient’s physical, psychological, and social functioning so that they may, by their own efforts, resume and maintain as normal a place as possible in the community
Exercise tolerance testing (also known as exercise testing or exercise stress testing) is used routinely in evaluating patients who present with chest pain, in patients who have chest pain on exertion, and in patients with known ischaemic heart disease.
The 6-minute walk test (6MWT) is an easy to perform and practical test that has been used in the assessment of patients with a variety of cardiopulmonary diseases including pulmonary arterial hypertension (PAH). It simply measures the distance that a patient can walk on a flat, hard surface in a period of 6 minutes.
Introduction to exercise electrocardiographyJavidsultandar
Exercise electrocardiography is a Non- invasive tool to evaluate the cardio vascular system's response to exercise under carefully controlled conditions.
Exercise is the body’s most common physiologic stress- most practical test of cardiac perfusion and function.
During exercise body increases its metabolic rate to greater than 20 times that of rest; cardiac out put as much as six fold. (depends on age,sex,type of exercise,size etc)
Evaluation of functional capacity, heart rate changes, burden of ectopy, and dynamic electrocardiographic changes during and after exercise have emerged as powerful prognostic indicators
coronary artery bypass graft surgery CABGSunil kumar
coronary artery bypass graft surgery, explanation of CABG on-pump and off-pump procedures, physiotherapy management after surgery. indications of CABG. description of the procedure, investigations before surgery, per operative and post operative management
Cardiac Rehabilitation has been defined as:
Coordinated, multifaceted interventions designed to optimize a cardiac patient’s physical, psychological, and social functioning so that they may, by their own efforts, resume and maintain as normal a place as possible in the community
Exercise tolerance testing (also known as exercise testing or exercise stress testing) is used routinely in evaluating patients who present with chest pain, in patients who have chest pain on exertion, and in patients with known ischaemic heart disease.
The 6-minute walk test (6MWT) is an easy to perform and practical test that has been used in the assessment of patients with a variety of cardiopulmonary diseases including pulmonary arterial hypertension (PAH). It simply measures the distance that a patient can walk on a flat, hard surface in a period of 6 minutes.
Introduction to exercise electrocardiographyJavidsultandar
Exercise electrocardiography is a Non- invasive tool to evaluate the cardio vascular system's response to exercise under carefully controlled conditions.
Exercise is the body’s most common physiologic stress- most practical test of cardiac perfusion and function.
During exercise body increases its metabolic rate to greater than 20 times that of rest; cardiac out put as much as six fold. (depends on age,sex,type of exercise,size etc)
Evaluation of functional capacity, heart rate changes, burden of ectopy, and dynamic electrocardiographic changes during and after exercise have emerged as powerful prognostic indicators
International Journal of Pharmaceutical Science Invention (IJPSI)inventionjournals
International Journal of Pharmaceutical Science Invention (IJPSI) is an international journal intended for professionals and researchers in all fields of Pahrmaceutical Science. IJPSI publishes research articles and reviews within the whole field Pharmacy and Pharmaceutical Science, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online
a clinical syndrome that results from inadequate tissue perfusion.
Hypovolemic shock - Blood or fluid loss, both leading to a decreased circulating blood volume, diastolic filling pressure, and volume.
Cardiogenic shock - due to cardiac pump failure related to loss of myocardial contractility/functional myocardium or structural/mechanical failure of the cardiac anatomy and characterized by elevations of diastolic filling pressures and volumes
Extra-cardiac/obstructive shock - due to obstruction to flow in the cardiovascular circuit and characterized by either impairment of diastolic filling or excessive afterload
Distributive shock - caused by loss of vasomotor control resulting in arteriolar/venular dilatation leading to a decrease in preload, with decreased, normal, or elevated cardiac output, depending on the presence of myocardial depression.
The primary treatment goals for patients with hepatitis B (HBV) infection are to prevent progression of the disease, particularly to cirrhosis, liver failure, and hepatocellular carcinoma (HCC).
Risk factors for progression of chronic HBV include the following :
Persistently elevated levels of HBV DNA and, in some patients, alanine aminotransferase (ALT), as well as the presence of core and precore mutations seen most commonly in HBV genotype C and D infections
Male sex
Older age
Family history of HCC
Alcohol use
Elevated alpha-fetoprotein (AFP)
Coinfection with hepatitis D (delta) virus (HDV), hepatitis C virus (HCV), or human immunodeficiency virus (HIV)
A synergistic approach of suppressing viral load and boosting the patient’s immune response with immunotherapeutic interventions is needed for the best prognosis. The prevention of HCC often includes the use of antiviral treatment using pegylated interferon (PEG-IFN) or nucleos(t)ide analogues.
HBV infection can be self-limited or chronic. No specific therapy is available for persons with acute hepatitis B; treatment is supportive.
Patients with acute hepatitis C virus (HCV) infection appear to have an excellent chance of responding to 6 months of standard therapy with interferon (IFN). Because spontaneous resolution is common, no definitive timing of therapy initiation can be recommended; however, waiting 2-4 months after the onset of illness seems reasonable.
Treatment for chronic HCV is based on guidelines from the Infectious Diseases Society of America (IDSA) and the American Associations for the Study of Liver Diseases (AASLD), in collaboration with the International Antiviral Society-USA (IAS-USA). These guidelines are constantly being updated. For more information, see HCV Guidance: Recommendations for Testing, Managing, and Treating Hepatitis C.
The guidelines propose that because all patients cannot receive treatment immediately upon the approval of new agents, priority should be given to those with the most urgent need.
The recommendations include the following :
Patients with advanced fibrosis, those with compensated cirrhosis, liver transplant recipients, and those with severe extraheptic hepatitis are to be given the highest priority for treatment
Based on available resources, patients at high risk for liver-related complications and severe extrahepatic hepatitis C complications should be given high priority for treatment
Treatment decisions should balance the anticipated reduction in transmission versus the likelihood of reinfection in patients whose risk of HCV transmission is high and in whom HCV treatment may result in a reduction in transmission (eg, men who have high-risk sex with men, active injection drug users, incarcerated persons, and those on hemodialysis)
Interstitial Lung Diseases [ILD] Approach to ManagementArun Vasireddy
Diffuse (interstitial) lung disease includes a wide variety of relatively uncommon conditions presenting with characteristic clusters of clinical features and marked by an immune response. There are over 200 specific diffuse lung diseases, many of unknown etiology. The combined incidence is 50 per 100,000, or 1 in 2000 people. Because these conditions cause aberrant lung function, morbidity and mortality due to lung injury and fibrosis are not uncommon. Both environmental and genetic factors are believed to contribute to the development of diffuse lung disease. Antigen processing and presentation are important in the development of the immune response seen in the disease, and it is thought that the likely candidate genes predisposing patients to this category of disease are those of the major histocompatibility complex. Genes that affect the immune, inflammatory, and fibrotic processes may also influence who develops the disease. If we can identify the genes that cause diseases characterized by lung injury and fibrosis, we can eventually develop genetic interventional approaches to treatment.
Amniotic Fluid Embolism [AFE] Approach to ManagementArun Vasireddy
Amniotic fluid embolism (AFE) is a life threatening obstetric emergency characterized by sudden cardiorespiratory collapse and disseminated intravascular coagulation.
Steiner and Luschbaugh first described AFE in 1941, after they found fetal debris in the pulmonary circulation of women who died during labor. Data from the National Amniotic Fluid Embolus Registry (USA) suggest that the process is more similar to anaphylaxis than to embolism, and the term anaphylactoid syndrome of pregnancy has been suggested because fetal tissue or amniotic fluid components are not universally found in women who present with signs and symptoms attributable to AFE.
The diagnosis of AFE has traditionally been made at autopsy when fetal squamous cells are found in the maternal pulmonary circulation; however, fetal squamous cells are commonly found in the circulation of laboring patients who do not develop the syndrome. The diagnosis is essentially one of exclusion based on clinical presentation. Other causes of hemodynamic instability should not be neglected.
Approach to Management of Upper Gastrointestinal (GI) BleedingArun Vasireddy
Upper gastrointestinal bleeding is gastrointestinal bleeding in the upper gastrointestinal tract, commonly defined as bleeding arising from the esophagus, stomach, or duodenum. Blood may be observed in vomit (hematemesis) or in altered form in the stool (melena). Depending on the severity of the blood loss, there may be symptoms of insufficient circulating blood volume and shock. As a result, upper gastrointestinal bleeding is considered a medical emergency and typically requires hospital care for urgent diagnosis and treatment. Upper gastrointestinal bleeding can be caused by peptic ulcers, gastric erosions, esophageal varices, and some rarer causes such as gastric cancer.
The initial assessment includes measurement of the blood pressure and heart rate, as well as blood tests to determine hemoglobin concentration. In significant bleeding, fluid replacement is often required, as well as blood transfusion, before the source of bleeding can be determined by endoscopy of the upper digestive tract with an esophagogastroduodenoscopy. Depending on the source, endoscopic therapy can be applied to reduce rebleeding risk. Specific medical treatments (such as proton pump inhibitors for peptic ulcer disease) or procedures (such as TIPS for variceal hemorrhage) may be used. Recurrent or refractory bleeding may lead to need for surgery, although this has become uncommon as a result of improved endoscopic and medical treatment.
Tachy Arrhythmias - Approach to ManagementArun Vasireddy
Tachyarrhythmias are disorders of heart rhythm which may present with a tachycardia i.e. a heart rate >100 bpm.
This article provides an overview of tachyarrhythmias in general and goes on to cover the most common tachyarrhythmias in more detail. The acute management of tachyarrhythmias, in an emergency setting, will be covered in the 'Acute' section of the fastbleep website.
Tachyarrhythmias are clinically important as they can precipitate cardiac arrest, cardiac failure, thromboembolic disease and syncopal events. As such, they crop up time and time again in exam papers and on the wards.
Tachyarrhythmias are classified based on whether they have broad or narrow QRS complexes on the ECG. Broad is defined as >0.12s (or more than 3 small squares on the standard ECG). Narrow is equal to or less than 0.12s. Broad QRS complexes are slower ventricular depolarisations that arise from the ventricles. Narrow complexes are ventricular depolarisations initiated from above the ventricles (known as supraventricular). One important exception is when there is a supraventricular depolarisation conducted through a diseased AV node. This will produce wide QRS complexes despite the rhythm being supraventricular in origin.
Scrub typhus is a mite-borne disease caused by Orientia tsutsugamushi (formerly Rickettsia tsutsugamushi). Symptoms are fever, a primary lesion, a macular rash, and lymphadenopathy. (See also Overview of Rickettsial and Related Infections.) Scrub typhus is related to rickettsial diseases.
Pulmonary edema is often caused by congestive heart failure. When the heart is not able to pump efficiently, blood can back up into the veins that take blood through the lungs. As the pressure in these blood vessels increases, fluid is pushed into the air spaces (alveoli) in the lungs.
The jugular venous pressure (JVP, sometimes referred to as jugular venous pulse) is the indirectly observed pressure over the venous system via visualization of the internal jugular vein. It can be useful in the differentiation of different forms of heart and lung disease.
A mosquito-borne viral disease occurring in tropical and subtropical areas.
Spreads by animals or insects
Requires a medical diagnosis
Lab tests or imaging often required
Short-term: resolves within days to weeks
Those who become infected with the virus a second time are at a significantly greater risk of developing severe disease.
Symptoms include high fever, headache, rash and muscle and joint pain. In severe cases there is serious bleeding and shock, which can be life threatening.
Treatment includes fluids and pain relievers. Severe cases require hospital care.
Adrenal gland & Cushing's Disease - Seminar August 2015Arun Vasireddy
A condition that occurs from exposure to high cortisol levels for a long time.
Fewer than 1 million cases per year (India)
Treatable by a medical professional
Requires a medical diagnosis
Lab tests or imaging always required
Chronic: can last for years or be lifelong
The most common cause is the use of steroid drugs, but it can also occur from overproduction of cortisol by the adrenal glands.
Signs are a fatty hump between the shoulders, a rounded face and pink or purple stretch marks.
Treatment options include reducing steroid use, surgery, radiation and medication.
Osteoporosis is a progressive systemic skeletal disease characterized by low bone mass and microarchitecture deterioration of bone tissue, leading to enhanced bone fragility and a consequent increase in fracture risk.
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Factory Supply Best Quality Pmk Oil CAS 28578–16–7 PMK Powder in Stockrebeccabio
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Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
2. INTRODUCTION
■ A cardiac stress test helps measure a heart's ability to respond to
external stress in a controlled clinical environment.
■ Aim is to assess the Coronary flow system, Perfusion & Cardiac function.
■ Stress response is induced by drugs or exercise under clinical supervision
3. Types of Stress testing
■ EXERCISE
a. Isotonic or Dynamic exercise
b. Isometric or Static exercise
c. Combined exercise
■ PHARMACOLOGICAL
a. Adenosine
b. Dipyridamole
c. Dobutamine
d. Isoproterenol
4. Indications for Non-Invasive Cardiac
StressTesting
I. Diagnosis of Obstructive Coronary Artery Disease
II. Risk Assessment and Prognosis in Patients with Symptoms or a
Prior History of Coronary Artery Disease
III. Post MI Risk Assessment and Prognosis
IV. Special Groups
Asymptomatic Patients
Post Revascularization Patients
Rhythm Disorders
Women
5. EXERCISE PHYSIOLOGY
– Adaptation to the increasing intensity of exercise by increasing the
metabolic rate by 20 times the BMR.
– Increase in CO from 5 lt/min to 25 lt/min
– Increased Heart rate
– Increased SBP (maintained Diastolic)
– Fall in Peripheral vascular resistance
6. METABOLIC EQUIVALENTS
1 MET Resting
2 METs Level walking at 2 mph
4 METs Level walking at 4 mph
<5 METs Poor prognosis; peak cost of basic activities of daily living
10 METs Prognosis with medical therapy as good as coronary artery
bypass surgery; unlikely to exhibit significant nuclear perfusion
defect
13 METs Excellent prognosis regardless of other exercise responses
18 METs Elite endurance athletes
20 METs World-class athletes
MET, metabolic equivalent, or a unit of sitting resting oxygen uptake; 1 MET = 3.5 mL/kg/min oxygen uptake
7. ACUTE CARDIOPULMONARY RESPONSETO
EXERCISE
Active muscles receive blood supply appropriate to their metabolic needs.
Heat generated by the muscles is dissipated.
Blood supply to the brain and heart is maintained.
■ This response requires a major redistribution of cardiac output along with a number of local
metabolic changes.
■ Thus, the limits of the cardiopulmonary system are defined by Total body oxygen consumption
(VO2max), which can be expressed by the Fick principle.
VO2max = maximal cardiac output × maximal arteriovenous oxygen difference
8. The cardiopulmonary limits (VO2max) are defined by the following:
• A central component (cardiac output) describes the capacity of the heart
to function as a pump.
• Peripheral factors (arteriovenous oxygen difference) describe the capacity
of the lung to oxygenate the blood delivered to it as well as the capacity of
the working muscle to extract this oxygen from the blood.
9. Central determinants of maximal oxygen
uptake
■ Heart Rate:
- First response by sympathetic and parasympathetic nervous system
- Vagal withdrawal is responsible for the initial 10 to 30 beats/ min change,
later largely caused by increased sympathetic outflow.
- Heart rate increases linearly with workload and oxygen uptake.
■ Heart rate response to exercise is influenced by age, type of activity, body position,
fitness, the presence of heart disease, medication use, blood volume, and
environment.
■ Of these, the most important factor is age; a significant decline in maximal heart
rate occurs with increasing age.
10. ■ Stroke Volume:
– product of stroke volume (the volume of blood ejected per heartbeat) and
heart rate determines cardiac output.
– It is equal to the difference between end-diastolic and end-systolic volume.
Thus, a greater diastolic filling (preload) will increase stroke volume.
– During exercise, stroke volume increases up to approximately 50% to 60% of
maximal exercise capacity, after which increased cardiac output is caused by
further increase in heart rate.
11. ■ End-Systolic Volume:
– depends on two factors: contractility and afterload.
– Contractility describes the force of the heart’s contraction. (ejection fraction)
– Increasing contractility reduces end-systolic volume, which results in a greater stroke
volume and thus greater cardiac output.
– Afterload is a measure of the force resisting the ejection of blood by the heart.
Increased afterload results in a reduced ejection fraction and increased end-diastolic
and end-systolic volumes.
– During dynamic exercise, the force resisting ejection in the periphery is reduced by
vasodilation, owing to the effect of local metabolites on the skeletal muscle vasculature.
Thus, despite even a five-fold increase in cardiac output among normal subjects during
exercise, mean arterial pressure increases only moderately.
13. AUTONOMIC CONTROL
NEURAL CONTROL MECHANISMS
■ Central command — neural impulses, arising from the central nervous system,
recruit motor units, excite medullary and spinal neuronal circuits, and cause the
cardiovascular changes during exercise.
■ Muscle afferents — muscle contraction stimulates afferent endings within the
skeletal muscle, which in turn reflexively evoke the cardiovascular changes.
■ Exercise pressor reflex, comprises all of the cardiovascular changes reflexly
induced from contracting skeletal muscle that cause changes in the efferent
sympathetic and parasympathetic outputs to the cardiovascular system that
are in turn responsible for increases in arterial blood pressure, heart rate,
myocardial contractility, cardiac output, and blood flow distribution.
14. GUIDELINES FOR PROPER SELECTION OF
PATIENTS
• Pretest Probability of Coronary Artery Disease by Symptoms, Gender, and Age
15. METHODOLOGY OF EXERCISETESTING
■ Commonly used is Dynamic/isotonic Exercise – defined as rhythmic
muscular activity resulting in movement, initiates a more appropriate
increase in cardiac output and oxygen exchange.
■ Involves greater muscle mass - Higher level of O2 uptake.
■ Bruce Protocol is commonly used.
16. Patient Assessment for Exercise
Testing
History
■ Medical diagnoses and past medical history—a variety of diagnoses should be reviewed, including
CVD, arrhythmias, syncope, or presyncope; pulmonary disease, including asthma, emphysema, and
bronchitis or recent pulmonary embolism; cerebrovascular disease, including stroke; PAD; current
pregnancy; musculoskeletal, neuromuscular, and joint disease
■ Symptoms—angina; chest, jaw, or arm discomfort; shortness of breath; palpitations, especially if
associated with physical activity, eating a large meal, emotional upset, or exposure to cold
■ Risk factors for atherosclerotic disease—hypertension, diabetes, obesity, dyslipidemia, smoking; if
the patient is without known CAD, determine the pretest probability of CAD
■ Recent illness, hospitalization, or surgical procedure
■ Medication dose and schedule
■ Ability to perform physical activity
17. Physical Examination
■ Pulse rate and regularity
■ Resting blood pressure while sitting and standing
■ Auscultation of the lungs, with speci c attention to uniformity
of breath sounds in all areas, particularly in patients with
shortness of breath or a history of heart failure or pulmonary
disease
■ Auscultation of the heart, particularly in patients with heart
failure or valvular disease
■ Examination related to orthopedic, neurologic, or other
medical
■ conditions that might limit exercise
22. Indications forTerminating Exercise
Testing
■ Drop in systolic blood pressure (SBP) despite an increase in workload
■ Moderate-to-severe angina
■ Increasing neurological symptoms (eg, ataxia, dizziness, near-syncope)
■ Signs of poor perfusion (cyanosis or pallor)
■ Subject’s desire to stop
■ Sustained ventricular tachycardia
■ ST elevation (> 1 mm) in leads (other than V 1 or aVR)
23. Safety and risks in exercise testing
■ Nonselected patient population: Mortality < 0.01%
■ Within 4 weeks of MI:
Mortality = 0.03% and
Morbidity = 0.09% (reinfarction, cardiac arrest)
24. Decreased
Myocardial
Perfusion
resulting in the
onset of Ischemia
Regional
Wall Motion
Changes
ST Segment
Changes
Development of
Angina
Start
Exercise
Timeline of Events During Exercise Stress
Time
The Ischemic Cascade
28. Duke’sTreadmill Score & prognostic Normogram
DUKE SCORE = 5 x ST seg deviation – (4 xTreadmill angina Index)
29. Advantages of the Standard Exercise EKG Stress Test
• Low Cost, Availability, Acceptability, Convenience
• Exercise tolerance determined
• Provides independent prognostic information
• Correlate symptoms with activity
• Assess rhythm, rate, BP, response to activity
Disadvantages of the Standard Exercise EKG Stress Test
• Limited Sensitivity and Specificity
• Does not localize ischemia
• No Estimate of LV Function
• Requires Cooperation and Ability to Walk
30. Pharmacological StressTesting
■ Planned only after ETT, is a diagnostic procedure in which cardiovascular stress
induced by pharmacologic agents is demonstrated in patients with decreased
functional capacity or in patients who cannot exercise.
■ Pharmacologic stress testing is used in combination with imaging modalities such
as radionuclide imaging and echocardiography.
■ Adenosine, dipyridamole, and dobutamine are the most widely available
pharmacologic agents for stress testing.
■ Regadenoson, an adenosine analog, has a longer half-life than adenosine, and
therefore a bolus versus continuous administration.
31. General indications:
■ Elderly patients with decreased functional capacity and possible CAD
■ Patients with chronic debilitation and possible CAD
■ Younger patients with functional impairment due to injury, arthritis, orthopedic problems,
peripheral neuropathy, myopathies, or peripheral vascular disease, in which a maximal heart rate is
not easily achieved with routine exercise stress testing, usually because of an early onset of fatigue
due to musculoskeletal, neurologic, or vascular problems rather than cardiac ischemia
■ Other cases, including patients taking beta-blockers or other negative chronotropic agents that
would inhibit the ability to achieve an adequate heart response to exercise
■ Patients with LBBB or ventricular pacemaker should undergo pharmacologic vasodilator stress
because exercise stress often produces a false-positive perfusion defect in the interventricular
septum.
32. Adenosine
■ Adenosine is a naturally occurring substance found throughout the body in various tissues. It
functions to regulate blood flow in many vascular beds, including the myocardium.
■ Dose - 0.14 mg/kg/min IV for 6 minutes (total cumulative dose of 0.84 mg/kg).
■ Direct coronary artery vasodilation induced by adenosine is attenuated in diseased coronary
arteries, which have a reduced coronary flow reserve and cannot further dilate in response to
adenosine.
■ In cases of severe vessel stenosis or total occlusions with compensatory collateral circulation, a
decrease in coronary blood flow may occur in the diseased coronary artery, thus inducing ischemia
via a coronary steal phenomenon.
■ This regional flow abnormality also induces a perfusion defect during radionuclide imaging.
33. ContraIndications for using cardiac
Vasodilators
■ active bronchospasm
■ Patients with more than first-degree heart block (without a ventricular-demand pacemaker)
■ Patients with an SBP less than 90 mm Hg
■ Patients using dipyridamole or methylxanthines (eg, caffeine and aminophylline)
34. Dipyridamole
■ Dipyridamole is an indirect coronary vasodilator that works by increasing intravascular adenosine
levels.
■ This occurs by the inhibition of intracellular reuptake and deamination of adenosine.
■ However, the increase in coronary blood flow induced by dipyridamole is less predictable than that of
adenosine.
■ Dose - Infused at a rate of 0.142 mg/kg/min IV for 4 minutes (not to exceed a cumulative dose of 0.57
mg/kg).
■ Contraindicated in Pts with active bronchospasm, more than first-degree heart block, SBP less than 90
mm Hg, using dipyridamole or methylxanthines
35. Dobutamine
■ Dobutamine is a synthetic catecholamine, which directly stimulates both beta-1 and beta-2 receptors.
■ A dose-related increase in heart rate, blood pressure, and myocardial contractility occurs.
■ As with physical exertion, dobutamine increases regional myocardial blood flow based on physiological
principles of coronary flow reserve.
■ A similar dose-related increase in subepicardial and subendocardial blood flow occurs within vascular
beds supplied by significantly stenosed arteries, with most of the increase occurring within the
subepicardium rather than the subendocardium.Thus, perfusion abnormalities are induced by the
development of regional myocardial ischemia.
■ Contraindicated in Patients with recent (1 wk) MI; unstable angina; significant aortic stenosis or
obstructive cardiomyopathy; atrial tachyarrhythmias with uncontrolled ventricular response; history of
ventricular tachycardia, uncontrolled HTN, or thoracic aortic aneurysm; or LBBB
36. Enoximone stress echocardiography
■ Dobutamine may sometimes induce ischemia in patients with a critical coronary stenosis,
which might mask hibernation by preventing the improvement in wall motion.
■ Another approach is the use of an imidazole phosphodiesterase inhibitor such as enoximone or
milrinone, drugs that are relatively unaffected by concurrent use of a beta-blocker and are used
for inotropic support in congestive heart failure.
■ Enoximone stress echocardiography as an additional stress testing modality was evaluated in
one study of 45 patients with chronic coronary artery disease and left ventricular dysfunction
who underwent echocardiography with both dobutamine and enoximone.
■ Both increased heart rate, but enoximone did not cause a significant change in systolic blood
pressure.The positive predictive value and specificity were similar between enoximone and
dobutamine.
37. STRESS ECHOCARDIOGRAPHY
■ 2D Echo imaging before, during and after cardiovascular stress
■ Cost effective means to assess CP
■ Stress ETT, Bicycle ergometer, Dobut
■ Compare wall motion at rest to stress can identify inducible ischemic
dysfx and assign a specific coronary territory
■ Sensitivity~88% (74-97): Specificity~84% (62-93%)
38. Stress Echocardiography
Advantages
Comprehensive – Ischemia,
EF, Valvular function
Widely available
Relatively low cost
Disadvantages
Limited by echocardiographic
windows and body habitus
Highly technician dependent
Steep technician learning
curve
Interpreting physician
dependent
40. Myocardial Perfusion Imaging
Cardiac ScinitgraphyTechniques utilised:
1) SPECT
2) PET
■ a radiotracer (Tc-99 mibi, thallium-201 or 99Tc-Tetrofosmin) is injected
■ scans are acquired with a gamma camera to capture images of the blood
flow.
■ Usually done on two separate days OR between 3-4 hrs:
1. After rest
2. After injection of stress stimulating drugs
41. MPI : SPECT Perfusion
■ Injected isotope extracted by viable myocytes
■ Photons emitted from myocardium in proportion to uptake, which is
related to perfusion
■ Gamma camera captures gamma photons and converts to digital data
representing magnitude and location of uptake
■ Single Photon Emission ComputedTomography SPECT images: Myocardial
perfusion images (MPI) represent distribution of perfusion throughout
myocardium
48. Myocardial Perfusion Imaging
Advantages
Applicable to almost all patients
Incremental value - prognosis,
guidance to therapy
Assessment of LV function
Disadvantages
Detects coronary
heterogeneity as a surrogate
for ischemia
Relatively Expensive
Artifacts
Isotope availability
Radiation exposure
49. Echocardiographic vs. Scinitigraphic Methods for the Detection of Occlusive
Coronary Artery Disease
SUMMARY
• Both techniques have comparable sensitivity and sensitivity
• Echocardiography is highly dependent on technician expertise
• Echocardiography is less costly
• Scintigraphy can be applied to almost all patients
50. PROGNOSIS
Provides useful Info on prognosis for
■ Pts with CAD who suffered a cardiac event or have underwent cardiac intervention
■ Patients with valvular heart disease
■ Pts with CHF
■ Adverse prognosis:
– Duration of symptom limited exercise of <5 METs
– Poor chronotropic heart response
– Failure of SBP rise above 120mmhg or persistent BP fall >10 mmHG during exercise
– Exercise induced ST elevation
– Clinical angina at low workloads
– Sustained VT during stress test
(VO2 Max) - usual measure of the capacity of the body to deliver and utilize oxygen
Cardiac output must closely match ventilation in the lung to deliver oxygen to the working muscle.
afterload (or aortic pressure, as is observed with chronic hypertension
A. ST Segment Depression > 0.1x mV 80mSec after the J Point
B. Horizontal ST Segment Depression > 0.1 mV
C. Downsloping ST Segment Depression
A. ST Segment Depression > 0.1x mV 80mSec after the J Point
B. Horizontal ST Segment Depression > 0.1 mV
Downsloping ST Segment Depression
TM AP score: 0 if no angina; 1 if angina occurred during test; 2 if angina was the reason for stopping.
Adenosine, dipyridamole, and regadenosine are cardiac vasodilators.
Dobutamine is a cardiac inotrope and chronotrope.
They dilate coronary vessels, which causes increased blood velocity and flow rate in normal vessels and less of a response in stenotic vessels. This difference in response leads to a steal of flow, and perfusion defects appear in cardiac nuclear scans or as ST-segment changes.
Once transported across cell membranes, adenosine interacts and activates the A1and A2 cell surface receptors. In the vascular smooth muscles, adenosine primarily acts by activation of the A2 receptor, which stimulates adenylate cyclase, leading to an increase in cyclic adenosine monophosphate (cAMP) production.
Increased cAMP levels inhibit calcium uptake by the sarcolemma, causing smooth muscle relaxation and vasodilation.
Activation of the vascular A1 receptor also occurs, which stimulates guanylate cyclase, inducing cyclic guanosine monophosphate production, leading to vasodilation.
Single photon emission tomography
Positron emission tomography
Single photon emission tomography
Positron emission tomography