Interpretation and limitations in stress testing.

In summary, although exercise is, as is every other procedure, imperfect with regard to sensitivity and specificity, it provides an invalualbe adjunct in the evaluation of patients with coronary disease. The test is simple, inexpensive, safe and rapidly performed and is an invaluable aid in screening patients with possible coronary disease. It is used in an asymptomatic population for industrial purposes, is useful in assessing the etiology of otherwise undiagnosed chest pain, helpful in evaluating the overall severity of ischemia [and therefore in culling-out those patients that might benefit from coronary angiography], is useful in following the course of patients with proven coronary disease [including those with acute myocardial infarction], and has found a place in the follow-up evaluation of individuals having aortocoronary bypass surgery. As a screening procedure, the treadmill test aids in seeking out that group of patients with coronary disease with potentially malignant lesions, i.e. main left coronary lesions, triple-vessel disease and [to a lesser extent] severe proximal left anterior descending coronary disease. Hence, the finding of marked depth of ST depression, prolonged duration of ischemia associated with deep ST segments, serious exercise-induced ventricular arrhythmias and hypotension produced during mild-to-moderate exercise might each be an indication of extensive coronary angiography. In many cases exercise testing is superior to coronary angiography, being a simpler, safer screening procedure, and a more functional test in documenting the presence or absence of coronary insufficiency.