Roles of exercise treadmill test in the diagnosis & risk stratification of cardiac channelopathies

Channelopathies are the leading causes of sudden cardiac death in patients without structural heart disease. Missing the diagnosis of high-risk but concealed channelopathies could have lethal clinical consequences. However, the diagnosis of channelopathies is often challenging due to the dynamic clinical presentations and elusive electrocardiographic manifestations of these diseases. An integrated approach including clinical assessment, repeated electrocardiography, drug provocation tests, exercise stress test and genetic studies is often required for establishing the diagnosis. Pharmacological provocation testing may have limited sensitivity and may be associated with false positive results. Inju-dicious use of genetic testing is not recommended due to its relatively low yield, limited cost-effectiveness and availability. Variants of unknown signi fi cance could complicate interpretation of genetic fi ndings. This review article focuses on the role of exercise stress testing in the diagnosis and risk strati fi cation of patients with Brugada syndrome, long QT syndrome and catecholaminergic polymorphic ventricular tachycardia.