Abstract
BACKGROUND: Left bundle branch area pacing (LBBAP) is an effective alternative to biventricular pacing for cardiac resynchronization therapy, particularly when coronary sinus anatomy is unfavorable. CASE SUMMARY: A 44-year-old man developed new-onset left bundle branch block and cardiomyopathy following surgical resection of a subaortic membrane. Left ventricular ejection fraction decreased to 30% despite optimal medical therapy. Conventional biventricular pacing failed due to repeated left ventricular lead dislodgment. LBBAP was performed using a deep septal pacing lead targeting the left bundle branch area. Following implantation, the patient experienced significant symptomatic improvement and recovery of left ventricular systolic function. DISCUSSION: Postoperative injury to the left bundle branch can result in severe electrical dyssynchrony and cardiomyopathy. This case demonstrates the feasibility and effectiveness of LBBAP even after surgical disruption of the proximal conduction system. TAKE-HOME MESSAGES: LBBAP is a viable alternative when conventional cardiac resynchronization therapy is not feasible. LBBAP may reverse postoperative left bundle branch block-associated cardiomyopathy.