Catheter ablation of premature ventricular complexes arising from the left fascicular system

Background Idiopathic premature ventricular complexes (PVCs) that originate from the left fascicular system have rarely been reported. Objective The present study aimed to investigate the electrophysiological characteristics and the ablation strategy for this category of PVCs. Methods Of 648 patients with idiopathic PVCs, 27 were enrolled in this study. All the PVCs presented with a relatively narrow QRS complex and right bundle branch block morphology. The mean QRS duration was 117.4 ± 8.6 ms. Radiofrequency catheter ablation was applied at the site recording the earliest fascicular potential (FP). Results The origin of PVCs was as follows: 15 originating from the left anterior fascicle, 7 originating from the left posterior fascicle, 2 originating from the left middle fascicle, and 3 originating from the common trunk of the left bundle branch. The earliest local FP preceded the onset of the QRS complex by 32.7 ± 6.4 ms. The immediate ablation success rate was 100%. Three patients had recurrent PVCs during follow-up. The total success rate of a single procedure was 88.9%. Conclusion Ablation of PVCs originating from the left fascicular system guided by an earliest presystolic FP was found to be safe and effective. Idiopathic premature ventricular complexes (PVCs) that originate from the left fascicular system have rarely been reported. The present study aimed to investigate the electrophysiological characteristics and the ablation strategy for this category of PVCs. Of 648 patients with idiopathic PVCs, 27 were enrolled in this study. All the PVCs presented with a relatively narrow QRS complex and right bundle branch block morphology. The mean QRS duration was 117.4 ± 8.6 ms. Radiofrequency catheter ablation was applied at the site recording the earliest fascicular potential (FP). The origin of PVCs was as follows: 15 originating from the left anterior fascicle, 7 originating from the left posterior fascicle, 2 originating from the left middle fascicle, and 3 originating from the common trunk of the left bundle branch. The earliest local FP preceded the onset of the QRS complex by 32.7 ± 6.4 ms. The immediate ablation success rate was 100%. Three patients had recurrent PVCs during follow-up. The total success rate of a single procedure was 88.9%. Ablation of PVCs originating from the left fascicular system guided by an earliest presystolic FP was found to be safe and effective.