cardiovascular disorders
Stress Testing
Introduction
In stress testing, the heart is monitored by electrocardiography (ECG) and often Myocardial Perfusion Imaging during an induced episode of increased cardiac demand so that ischemic areas potentially at risk of infarction can be identified. In patients with Stress testing is used for Diagnosing Overview of Coronary Artery Disease None Stratifying risk in patients with known CAD Monitoring patients with known CAD Stress testing is less invasive and less expensive than Cardiac Catheterization , and it detects abnormalities of blood flow; however, it is less accurate for diagnosis in patients with a low pretest likelihood of CAD. It can define the functional significance of abnormalities in coronary artery anatomy identified with coronary angiography during catheterization. Because coronary artery plaques that are not significantly stenotic (ie, do not result in ischemia during stress testing) may nonetheless rupture and cause an acute coronary syndrome, a normal stress test result does not guarantee future freedom from myocardial infarction. Risks of stress testing include infarction and sudden death, which occur in about 1/5000 patients tested. Stress testing has several absolute and relative contraindications Absolute contraindicationsto exercise stress testing are Overview of Acute Coronary Syndromes (ACS) (myocardial infarction within 48 hours or uncontrolled unstable angina) Aortic Dissection if acute Aortic Stenosis if symptomatic or severe Overview of Arrhythmias if symptomatic or hemodynamically significant Heart Failure (HF) if decompensated Myocarditis if acute Pericarditis if acute Pulmonary Embolism (PE) if acute Pulmonary infarction if acute Relative contraindicationsto exercise stress testing include Atrioventricular Block if high-degree Bradyarrhythmias Electrolyte imbalance Hypertension (systolic blood pressure [BP] Hypertrophic Cardiomyopathy None 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 