P6-122: Regional myocardial strain during hemodynamically stable ventricular tachycardia

Abstract

Speckle tracking is a newly available echocardiographic technique used to derive measurements of regional myocardial strain as a function of time. Preliminary data supports that measurements of myocardial strain are more sensitive for detection of myocardial ischemia than conventional wall motion analysis. To our knowledge, ultrasonic strain measurements during ventricular arrhythmia have not been reported. A 75 year old male with ischemic cardiomyopathy developed sustained ventricular tachycardia (VT) with a RBBB, superior axis, during Dobutamine infusion. Echocardiographic studies were being performed before and during hemodynamically stable VT at 160 bpm. Post-processing of the gray scale images obtained from parasternal long axis views (GE Vivid 7) allowed for speckle tracking algorithms to derive regional myocardial transverse strain data during sinus rhythm (NSR) and VT. In NSR (top of graph) septal, S, and posterior, P, regions demonstrated normal appearing strain - time curves with peak systolic strain values of 40% and 60%, respectively. In VT (bottom of graph), peak S and P strain measured < 10% and 60%, respectively. Significant regional impairments in strain during VT were noted in S but not P regions. Further studies of the effects of VT on myocardial strain are warranted.