Performance of the Exercise Test

Each year, over 1 million Americans experience a nonfatal or fatal myocardial infarction or sudden death from coronary heart disease (CHD) [1]. Unfortunately, death or myocardial infarction is the first symptom in 55% of patients with coronary artery disease [2] and is usually due to dislodgement of a plaque causing acute coronary occlusion. However, about 30% of these patients present with ischemia and have concurrent chest pain. In these individuals, exercise treadmill testing is a practical and the most commonly performed test to identify or confirm the presence of latent coronary artery disease [2]. In addition, an abnormal test has been shown to have definite predictive value. It is well known that when symptoms of typical angina are present, coronary disease can be predicted with considerable reliability. Even when there is no history of pain, there is still a strong possibility of significant coronary disease in patients with specific risk factors. Also, the reliability of the test in asymptomatic patients is improved when testing patients with a higher prevalence of the disease. Exercise testing may also be used to measure functional capacity, assess the patient’s prognosis in coronary artery disease, and evaluate the patient’s treatment for hypertension, certain arrhythmias, angina, and congestive heart failure. It can be beneficial for patients who will be involved in exercise rehabilitative programs. It may be useful for predicting mortality risk among patients who plan to start an exercise program, whose job affects public safety (airline pilot), or who have specific medical conditions (diabetes or chronic renal insufficiency). The inherent accuracy of the test is defined by the sensitivity and specificity. The results of the test when applied to an individual depend on the prevalence of disease in the population to which the patient belongs. So, the two most important factors in the analysis of patients undergoing stress testing are the pre-test prevalence of disease and the sensitivity and specificity of the test. Various types of chest pain affect the probability of disease in each patient. By dividing the patients into one