Internal Cardioverter Defibrillator Indications and Therapies after Atrial Baffle Procedure for d-Transposition of the Great Arteries: A Multicenter Analysis.

Background: Sudden cardiac death (SCD) is the most important cause of late mortality after atrial baffle procedure for d-transposition of the great arteries (d-TGA). Experience with internal cardioverter defibrillator (ICD) therapy in this population is limited. We conducted a multicenter cohort study to determine the current state of ICD therapy in individuals after atrial baffle procedure.

Methods: Demographic and clinical data as well as data on device implantation, programming, ICD discharges, and complications after atrial baffle procedure for d-TGA from four German centers were analyzed retrospectively.

Results: ICD implantation was undertaken in 33 subjects. ICD implantation was undertaken as primary prevention in 29 (88%) and secondary prevention in four (12%) individuals. There were 21 (64%) subjects with atrial reentrant tachycardia (IART). During a median follow-up of 4.8 years, seven appropriate ICD therapies were delivered in three (10%) individuals with primary prevention indication. No appropriate shocks were documented in subjects with secondary prevention indication. A total of 12 inappropriate ICD discharges occurred in eight (24%) individuals due to IART (n = 6) or lead failure (n = 2). ICD-related complications were noted in seven individuals (21%): lead dislodgement/failure in five (15%) and ICD infection in two subjects (6%).

Conclusions: The majority of individuals received an ICD for primary prevention of SCD, thus representing a liberal attitude of physicians for ICD implantation. During a median follow-up of 4.8 years, the rate of appropriate ICD therapies was low and clearly exceeded by inappropriate ICD discharges. Lead failure and IART were present in >20% of the individuals and were frequent reasons for inappropriate ICD discharges. Facing these results, rigorous treatment of IART and careful ICD programming seems mandatory.