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.
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
J Am Coll Cardiol. 2006 Aug 15;48(4):798-804
Nanthakumar K, Billingsley IM, Masse S, Dorian P, Cameron D, Chauhan VS, Downar E, Sevaptsidis E
Pacing Clin Electrophysiol. 2005 Sep;28(9):997-9
Toal S, Chauhan VS
Am J Physiol Heart Circ Physiol. 2006 Jan;290(1):H79-86
Chauhan VS, Downar E, Nanthakumar K, Parker JD, Ross HJ, Chan W, Picton P
Pacing Clin Electrophysiol. 2004 Aug;27(8):1077-84
Chauhan VS, Nair GM, Sevaptisidis E, Downar E
J Cardiovasc Electrophysiol. 2003 Jun;14(6):673
Chauhan VS, Downer E, Shah P
Pacing Clin Electrophysiol. 2003 Apr;26(4 Pt 1):902-5
Sardana R, Chauhan VS, Downar E
Am Heart J. 2002 Nov;144(5):858-64
Chauhan VS, Krahn AD, Walker BD, Klein GJ, Skanes AC, Yee R



Associate Professor, Department of Physiology, University of Toronto