Exercise testing is used routinely for the assessment of CAD and often overlooked following coronary angiography. Exercise testing should be performed in patients with unexplained cardiac arrest to unmask phenotypic evidence of inherited arrhythmic syndrome or exercise-induced arrhythmia such as polymorphic ventricular tachycardia in CPVT, sustained ventricular tachycardia in ARVC and QT prolongation/T wave changes in LQTS. Type 1 LQTS (LQT1) is associated with marked prolongation of QTc interval at peak exercise. Exercise testing may also induce ECG changes in Brugada syndrome.
Exercise testing should be accompanied by continuous ECG monitoring with measurement of the ST segment, QT interval and blood pressure measurements. Intravenous beta-blocking agents and resuscitation equipment should be available in the event of exercise-induced ventricular arrhythmia. The failure of blood pressure to increase or a drop in blood pressure in response to upright exercise testing can identify patients with hypertrophic cardiomyopathy at increased risk of sudden death.