Stress testing has several absolute and relative contraindications Absolute contraindications to exercise stress testing are Acute coronary syndrome (myocardial infarction within 48 hours or uncontrolled unstable angina) Aortic dissection if acute Aortic stenosis if symptomatic or severe Arrhythmias if symptomatic or hemodynamically significant Heart failure if decompensated Myocarditis if acute Pericarditis if acute Pulmonary embolism if acute Pulmonary infarction if acute Relative contraindications to exercise stress testing include Atrioventricular block if high-degree Bradyarrhythmias Electrolyte imbalance Hypertension (systolic blood pressure [BP] > 200 mm Hg or diastolic BP > 110 mm Hg) Hypertrophic obstructive cardiomyopathy Inability to exercise adequately due to mental or physical impairment Stenosis of heart valve if moderate or severe Stenosis of left main coronary artery Systemic illness Tachyarrhythmias Stress Test Methodology Cardiac demand can be increased by Exercise Drugs (pharmacologic stress) Patients must fast for 4 to 6 hours before the test.