Related Experiment Video
Updated: Jun 15, 2026

Transthoracic Echocardiographic Examination in the Rabbit Model
Published on: June 1, 2019
A couplet of PVCs with different QRS morphologies arising from a single origin in the left ventricular outflow tract
Takumi Yamada1, H Thomas McElderry, Harish Doppalapudi
1University of Alabama, Birmingham, AL, USA. takumi-y@fb4.so-net.ne.jp
Abstract:
A 59-year-old man with two different premature ventricular contractions (PVCs) forming a couplet underwent electrophysiological testing. Although pacing from the aorto-mitral continuity (AMC) produced an excellent pace map of one type of PVCs, a radiofrequency application within the right coronary cusp (RCC) eliminated all the PVCs. This case demonstrates that a single origin with two breakout sites in the left ventricular ostium (LVos) may result in a couplet consisting of different PVCs and preferential conduction from the RCC to AMC may also occur. These possibilities should be kept in our mind when predicting sites of origin of LVos ventricular arrhythmias.
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