Vijay S Chauhan, MD, FRCPC

Ventricular tachyarrhythmias are an important mode of sudden death in patients with cardiomyopathy. Animal studies suggest that abnormal ventricular repolarization can lead to ventricular arrhythmias. In humans, the relevance of cardiac repolarization as a substrate for arrhythmogenesis is not well understood. Our laboratory is characterizing the spatiotemporal distribution of ventricular repolarization in patients with cardiomyopathy and defining the dynamic range of repolarization in response to physiologic stress that can trigger ventricular arrhythmias. The experiments involve body surface and intracardiac recordings of repolarization under varying physiological conditions. Using linear and nonlinear dynamics, several aspects of cardiac repolarization are quantified including spatiotemporal heterogeneity, restitution, memory and alternans. The knowledge gained from our experiments will provide better understanding of the pathogenesis of lethal ventricular arrhythmias in cardiomyopathic patients which may lead to the development of novel antiarrhythmic therapies.
Heart Rhythm. 2008 Jul;5(7):1029-35
Umapathy K, Masse S, Kolodziejska K, Veenhuyzen GD, Chauhan VS, Husain M, Farid T, Downar E, Sevaptsidis E, Nanthakumar K
J Cardiovasc Electrophysiol. 2008 Nov;19(11):1219
Chauhan VS, Hameedullah I, Nanthakumar K, Downar E
J Heart Lung Transplant. 2007 Jun;26(6):630-6
Mamalias N, Li RK, Weisel RD, Dorian P, Chauhan VS, Nanthakumar K
Am J Physiol Heart Circ Physiol. 2007 Jun;292(6):H2589-97
Massé S, Downar E, Chauhan V, Sevaptsidis E, Nanthakumar K
Europace. 2007 Jan;9(1):10-9
Masse S, Downar E, Chauhan V, Sevaptsidis E, Nanthakumar K
Am J Physiol Heart Circ Physiol. 2007 Mar;292(3):H1262-8
Selvaraj RJ, Picton P, Nanthakumar K, Chauhan VS
J Cardiovasc Electrophysiol. 2006 Oct;17(10):1150-2
Omar AR, Harris L, Cameron DA, Chauhan VS
Pacing Clin Electrophysiol. 2006 Aug;29(8):910-3
Calton R, Cameron D, Cusimano RJ, Merchant N, Chauhan V



Associate Professor, Department of Physiology, University of Toronto