Implantation of cardiac resynchronization therapy defibrillator with left bundle branch pacing in a patient with mirror-image dextrocardia: a case report.

Mirror-image dextrocardia is a rare congenital malformation of visceral transposition, and its completely reversed cardiac anatomical structure poses great challenges to cardiac resynchronization therapy (CRT). Currently, clinical experience with left bundle branch pacing (LBBP) in such special patients remains extremely limited. This article reports a case of a 73-year-old male patient diagnosed with mirror-image dextrocardia complicated by advanced heart failure and complete left bundle branch block (CLBBB). Through preoperative mirror-image adaptation of electrocardiogram and digital subtraction angiography (DSA) systems, combined with reverse personalized heat shaping of the delivery sheath during the procedure, we successfully completed the implantation of an LBBP-based cardiac resynchronization therapy defibrillator (CRT-D). This case is extremely rare and provides valuable insights for the management of such patients.