Pseudo–Left Ventricular Summit Premature Ventricular Contraction in a Patient With Abnormal Intraventricular Conduction

Figures

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  Figure 1. 12-Lead Electrocardiogram Demonstrating Frequent Monomorphic Premature Ventricular Complexes

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  Figure 2. Electrocardiogram During Electroanatomic Mapping, Showing an Early Transition in Lead V1, a Pattern Break in Lead V2, and an aVL/aVR Q-Wave Ratio of Approximately 2.8

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  Figure 3. Electroanatomic Mapping of the Left and Right Ventricles (A) Three-dimensional left ventricular mapping showing the earliest activation site (green tag, 19 ms). Ablation at this site failed to eliminate the premature ventricular complexes (PVCs). (B) The earliest activation site was subsequently identified in the right ventricular outflow tract, where ablation successfully eliminated the PVCs.

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  Figure 4. Electrogram Recordings and Pace Mapping at the Target Site (A) Earliest activation site identified in the right ventricular outflow tract, 30 ms pre-QRS. (B) Pace mapping at this site reproduced a morphology closely matching the clinical premature ventricular complexes, with a pacing score of 95%.

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  Figure 5. Detailed Analysis of the Baseline ECG Blue circles highlight narrow QRS complexes, most apparent in leads V2, V3, and lead II. Red circles indicate wider QRS complexes with inversion in V2 and V3, consistent with intraventricular conduction delay.

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  Visual Summary. Pseudo–Left Ventricular Summit Premature Ventricular Complex (A) Surface ECG demonstrating features suggestive of a left ventricular summit origin, including a V2 pattern break, a negative QRS complex in lead I, and a more negative aVL compared with aVR (see also D). (B) Three-dimensional left ventricular mapping showing the earliest activation site (green tag, 19 ms), where ablation was ineffective. (C) Earliest activation subsequently identified in the right ventricular outflow tract, where ablation successfully eliminated the premature ventricular complexes. (D) Detailed analysis of the baseline ECG. Blue circles highlight narrow QRS complexes (most prominent in leads V2, V3, and II). Red circles indicate wider and inverted QRS complexes in V2 and V3, consistent with subtle intraventricular conduction delay.