Life threatening causes of syncope: Channelopathies and cardiomyopathies

•Syncope due to cardiomyopathies or channelopathies is potentially lethal.•SCD from cardiomyopathies and channelopathies is often preventable with diagnosis.•Diagnosis is difficult and requires thorough testing.•Patient history, ECG and rhythm testing help direct advanced testing.•Exercise, provocative, and genetic testing provide focused testing.

Syncope is common, has a high recurrence rate and carries a risk of morbidity and, dependent on the cause, mortality. Although the majority of patients with syncope have a benign prognosis, syncope as a result of cardiomyopathy or channelopathy carries a poor prognosis. In addition, the identification of these disorders allows for the institution of treatments, which are effective at reducing the risk of both syncope and mortality. It is for these reasons that the identification of a cardiomyopathy or channelopathy in patients with syncope is crucial. This review article will describe the characteristics of common cardiomyopathies and channelopathies and their investigation.