Author + information
- Received March 22, 2016
- Revision received April 25, 2016
- Accepted May 12, 2016
- Published online April 17, 2017.
- Francesco Santoro, MD∗ (, )
- Kentaro Hayashi, MD,
- Karl-Heinz Kuck, MD and
- Feifan Ouyang, MD
- ↵∗Address for correspondence:
Dr. Francesco Santoro, Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstrasse 5, Hamburg 20099, Germany.
A 72-year-old man, with biological aortic valve and preserved ejection fraction, was referred for symptomatic palpitation. Rest electrocardiography showed sinus rhythm and right bundle branch block (RBBB). An electrophysiology study showed normal baseline interval parameters except for prolonged HV interval (85 ms) (Figure 1A). During ventricular electrical stimulation, a ventricular tachycardia with RBBB morphology was induced (Figure 1B). The His potential preceded the ventricular one during ventricular tachycardia (VT) induction. HV interval during arrhythmia was 90 ms (Figure 1C). Bundle branch re-entrant VT was diagnosed and radiofrequency ablation of RBB was performed. As during sinus rhythm and during VT, no clear RBB signals were found, radiofrequency applications were given in the right ventricle septum at 2 cm from the His area. To avoid complete heart block, radiofrequency ablation was performed where the His potential was not captured during pacing.
Due to VT recurrence, a left bundle branch (LBB) ablation involving the posterior side was performed and VT was not inducible (Figure 1D). Before discharge, due to evidence of intermittent left bunch branch block (LBBB) and RBBB at rest electrocardiography, the patient underwent to a double-chamber pacemaker implantation. No recurrences at follow-up were found.
We propose that during BBR-VT with RBBB morphology, the following circuit is present: the left posterior fascicle acts as anterograde limb and RBB as a retrograde. Therefore 1 limb of the circuit could be targeted during ablation.
RBB ablation was the first therapy of choice in order to reduce the chance of complete heart block, but in the absence of clear RBB signals, additional left fascicular ablation (due to VT recurrence) was employed, resulting in this complication.
Dr. Kuck has received honoraria from Medtronic, St. Jude Medical, and Biosense Webster. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
All authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the JACC: Clinical Electrophysiology author instructions page.
- Received March 22, 2016.
- Revision received April 25, 2016.
- Accepted May 12, 2016.
- 2017 American College of Cardiology Foundation