Body surface mapping criteria for diagnosis of left ventricular hypertrophy associated with complete right bundle...

The standard electrocardiographic (ECG) criteria for left ventricular hypertrophy are unreliable in patients with complete right bundle branch block. This study was undertaken to formulate criteria for diagnosing these patients by using body surface mapping. The echocardiographic left ventricular mass was calculated by the Penn method from M-mode measurements. Of 56 patients, 27 were defined as having left ventricular hypertrophy with a left ventricular mass of 215 g or more. Isopotential and isointegral maps of the QRS complex were observed. The QRS isointegral maps were separated into two parts at the end of the downstroke of the initial R wave of vector spatial magnitude. The body surface mapping criteria with the highest sensitivity were EPmax (maximum of early part of the QRS) 45 microV.s or greater (sensitivity 93%, specificity 90%), EPmax/d (EPmax averaged by EP duration) 0.8 mV or greater (sensitivity 93%, specificity 97%), and Max (initial maximum) 2.2 mV or greater (sensitivity 89%, specificity 90%). These results suggest that body surface mapping is a useful technique in diagnosing patients with left ventricular hypertrophy and right bundle branch block.