Resynchronization therapy with His bundle pacing in a patient after coronary sinus reducer implantation.

Symptomatic heart failure patients with ischemic heart disease may require both coronary sinus reducer (CSR) implantation due to refractory angina pectoris and cardiac resynchronization therapy (CRT). Optimal approach to CRT in these patients is unknown as CSR implantation in the distal coronary sinus could deter left ventricular lead placement and thus preclude conventional CRT with biventricular pacing. We present a 70-year-old patient with ischemic cardiomyopathy and wide QRS complex after CSR implantation in whom we achieved successful cardiac resynchronization with His bundle pacing (HBP). HBP led to acute improvement in hemodynamic parameters and exercise capacity that persisted at follow-up. This case represents the first description of successful CRT with HBP in a patient after CSR implantation. HBP could present a feasible and safe resynchronization approach in these patients. < Learning objective: Optimal approach to cardiac resynchronization therapy in patients after coronary sinus reducer (CSR) implantation remains unknown as CSR implantation in the distal coronary sinus may deter left ventricular lead implantation and thus preclude conventional biventricular pacing. His bundle pacing could present a feasible and safe resynchronization approach in this growing group of patients.>.