Left bundle branch pacing in anatomically repaired congenitally corrected transposition of the great arteries: a case report

There are currently different approaches to conduction system pacing in unrepaired congenitally corrected transposition of the graet arteries (CCTGA) patients. However, these therapies are not feasible when patients have undergone anatomic repair.

We describe our approach and considerations for left bundle branch (LBB) area pacing in a 12-year-old patient with CCTGA after double switch operation using Rastelli repair. Three-dimensional reconstructions derived from cardiac CT were both printed as a dry model and uploaded in a virtual reality environment to enhance anatomical understanding and simulate the procedure. Across the Senning baffle, a SelectSecure 3830 lead was delivered through the Attain Select II 6248V-90P deflectable delivery sheath and positioned at the mid-inferior interventricular septum of the sub-pulmonary right ventricle. Non-selective LBB capture was suspected by a pacing stimulus to peak S wave of 83 ms, with final paced QRS duration from 219 to 138 ms. Despite early symptomatic improvement, systemic ventricular function did not recover sufficiently to obviate the need for heart transplantation, which was successfully performed two months post-procedure.

We demonstrate the feasibility of LBB area pacing in anatomically repaired CCTGA. Rigorous pre-procedural planning with 3D modelling was crucial to overcome the technical and diagnostic challenges in this complex congenital heart disease.