Assessing repolarization: Alternate hypotheses

Abstract

Sudden cardiac arrest remains a leading cause of death, the underlying cause typically being ventricular tachycardia or ventricular fibrillation (VT/VF). The mechanism for VT/VF is thought to be reentry in most cases, but our inadequate understanding of how reentry is initiated hampers our ability both to identify those at greatest risk and to design preventive strategies. The theory of repolarization alternans has been proposed as an explanation of how reentry is induced in the absence of identifiable anatomic obstacles.