Heet Desai, C Anwar A Chahal, Edmond K Obeng-Gyimah
BACKGROUND: Conduction disturbances are common after transcatheter aortic valve replacement (TAVR), usually manifesting as atrioventricular block. Rarely, injury to the His-Purkinje system may create substrate for bundle branch reentrant ventricular tachycardia (BBR-VT).
CASE SUMMARY: A 78-year-old man developed new conduction abnormalities after TAVR and was discharged on ambulatory monitoring. Loop recorder interrogation revealed recurrent symptomatic wide-complex tachycardia. Repeat electrophysiology study demonstrated inducible sustained monomorphic ventricular tachycardia with His-V-His activation confirming BBR-VT. Two reciprocal reentrant circuits were inducible: one with antegrade conduction over the right bundle branch (left bundle branch block-pattern QRS) and the other in the reverse direction (right bundle branch block-pattern QRS). Right bundle branch ablation terminated the arrhythmia and induced persistent right bundle branch block. Given paroxysmal complete atrioventricular block, a dual-chamber pacemaker was implanted. With preserved ventricular function and no additional substrate, implantable cardioverter-defibrillator insertion was deferred.
DISCUSSION: BBR-VT is a rare but serious complication of post-TAVR conduction injury. Early recognition allows curative ablation and tailored device therapy.
TAKE-HOME MESSAGES: Post-TAVR conduction delay can facilitate BBR-VT. Successful ablation with pacing may avoid implantable cardioverter insertion implantation in selected patients.