Cardiac stress test

cardiac stress tests( excercise and pharmacological testing)

1. Cardiac stress tests Porya Hassan A badi

2. Introduction Diagnostic test for coronary artery disease Main aim is to assess the coronary flow system Measures ability of heart to respond to stress Stress is induced by drugs or exercise under clinical supervision

3. Clinical case 50 y/o female with diabetes, HTN, smoker Nonspecific substernal chest pain Slight dyspnoea ECG nonspecific Normal cardiac markers

4. Indications Diagnosis of coronary disease in patients with: Stable chest pain Unstable chest pain stabilised with therapy Previous MI Post revascularisation (CABG)

5. Contra-indications Acute myocardial infarction (within 2 d) Unstable angina not previously stabilized by medical therapy Uncontrolled cardiac arrhythmias causing symptoms or hemodynamic compromise Symptomatic severe aortic stenosis Uncontrolled symptomatic heart failure Acute pulmonary embolus or pulmonary infarction Acute myocarditis or pericarditis Acute aortic dissection

6. TYPES OF STRESS TESTING 6 EXERCISE Treadmill Bicycle PHARMACOLOGICAL Adenosine Dipyridamole Dobutamine Isoproterenol

7. Physical stimulation Test is done by exercise on treadmill or pedaling an stationary bicycle. Constantly monitored (ECG,BP and heart rate)

8. 8 TEST OF CHOICE IN THOSE WITH: NORMAL BASLINE ECG ABLE TO EXERCISE NO PRIOR REVASCULARISATION

9. How long? How fast? 9 Maximal Test : The patient achieves 85% of MPHR ( maximal predicted HR = 220 - Age ) Submaximal Test : The patient becomes symptomatic  chest pain, dyspnea (MPHR generally not achieved)

10. When the termination is needed? 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 )

11. Safety and risk of exercise test Nonselected patient population: Mortality < 0.01% Within 4 weeks of MI: Mortality = 0.03% and Morbidity = 0.09% ( reinfarction , cardiac arrest)

12. Pharmacological Stress Test Stress is induced using agents such as : Vasodilators such as: Adenosine and Dipyridamole  not used asthma or COPD B2 agonist such as: Dobutamine

13. INDICATIONS OF PHARMACOLOGICAL STRESS TESTING 13 Patients inability to exercise adequately because of physical or psychological limitations. The chosen test cannot be performed readily with exercise (e.g. PET scanning).

14. METHODS OF DETECTING ISCHEMIA DURING STRESS TESTING 14 Electrocardiography Echocardiography Myocardial perfusion imaging Positron emission tomography Magnetic resonance imaging

15. ECG changes

16. Stress echocardiography echocardiography is performed both before and after the exercise used to detect: Wall motion abnormalities Ejection fraction Valvular heart disease

17. Nuclear stress test (Myocardial perfusion imaging) a radiotracer (Tc-99 sestamibi or thallium) is injected scans are acquired with a gamma camera to capture images of the blood flow . Usually done on two separate days: After rest After injection of stress stimulating drugs