Transvenous Coronary Sinus Lead Placement in Systemic Right Ventricle With D-TGA and Atrial Baffle

Background: Cardiac resynchronization therapy for systemic right ventricular dysfunction in D-transposition of the great arteries (D-TGA) and atrial switch operations usually require repeat sternotomy for epicardial lead placement. Case Summary: We report findings in a 33-year-old woman who underwent D-TGA and atrial baffle surgery with dual-chamber pacemaker implantation who developed progressive systemic right ventricular failure (ejection fraction: 19%) with high ventricular pacing burden. Cardiac computed tomography identified feasible coronary sinus anatomy draining into the systemic venous atrium, enabling a transvenous approach. At 12-month follow-up, she demonstrated enhanced functional capacity, reduced N-terminal pro–B-type natriuretic peptide, and narrower QRS duration. Discussion: We report the first successful transvenous coronary sinus lead placement in a patient with prior atrial baffle surgery, highlighting the importance of imaging in assisting procedural planning. Take-Home Message: Imaging in the setting of D-TGA patients with right ventricular dysfunction may identify accessible coronary sinus anatomy, eliminating the need for repeat sternotomy while providing cardiac resynchronization therapy benefits.