- Jonathan Hill,
- Adam Timmis
Exercise tolerance testing is an important diagnostic and prognostic tool for assessing patients with suspected or known ischaemic heart disease. During exercise, coronary blood flow must increase to meet the higher metabolic demands of the myocardium. Limiting the coronary blood flow may result in electrocardiographic changes. This article reviews the electrocardiographic responses that occur with exercise, both in normal subjects and in those with ischaemic heart disease.
ST segment depression (horizontal or downsloping) is the most reliable indicator of exercise-induced ischaemia
Exercise tolerance testing (also known as exercise testing or exercise stress testing) is used routinely in evaluating patients who present with chest pain, in patients who have chest pain on exertion, and in patients with known ischaemic heart disease.
Diagnostic indications for exercise testing
Assessment of chest pain in patients with intermediate probability for coronary artery disease
Assessment of symptoms (for example, presyncope) occurring during or after exercise
Prognostic indications for exercise testing
Risk stratification after myocardial infarction
Risk stratification in patients with hypertrophic cardiomyopathy
Evaluation of revascularisation or drug treatment
Evaluation of exercise tolerance and cardiac function
Assessment of cardiopulmonary function in patients with dilated cardiomyopathy or heart failure
Assessment of treatment for arrhythmia
Exercise testing has a sensitivity of 78% and a specificity of 70% for detecting coronary artery disease. It cannot therefore be used to rule in or rule out ischaemic heart disease unless the probability of coronary artery disease is taken into account. For example, in a low risk population, such as men aged under 30 years and women aged under 40, a positive test result is more likely to be a false positive than true, and negative results add little new information. In a high risk population, such as those aged over 50 with typical angina symptoms, a negative result cannot rule out ischaemic heart disease, though the …