Lesion-specific differences for implantable cardioverter defibrillator therapies in adults with congenital heart disease.

BACKGROUND: Sudden cardiac death is a major cause of late mortality in adults with congenital heart disease (ACHD). While data exist for adults with repaired Tetralogy of Fallot (TOF), little is known about those with non-TOF lesions. We examined the relative rates in implantable cardioverter defibrillator (ICD) therapy according to congenital lesion type in a large-volume adult congenital heart center.

METHODS: A cohort of 59 individuals (median follow up time, 3.2 years range 0-10) with ACHD and ICDs was stratified according to underlying congenital lesion and implant indication. Appropriate therapies were defined as any therapy for a physician-adjudicated ventricular arrhythmia. Rates of inappropriate and appropriate ICD therapies were analyzed according to several relevant clinical variables.

RESULTS: Thirty-three (56%) TOF, 15 (25.4%) L- or D-transposition of great arteries, and 11 (18.6%) with other lesions were included in the analysis. Approximately half (52.5%) were implanted for primary prevention indications. During follow-up, 12 (20.3%) patients received appropriate ICD therapies and 13 (22%) patients received inappropriate therapies. The incidence of appropriate shocks among patients with TOF was 27.3% (9/33) compared to 11.5% (3/26) among non-TOF diagnoses during the follow-up time (p = 0.043).

CONCLUSIONS: ACHD patients with non-TOF congenital lesions are significantly less likely to receive appropriate ICD therapy than those with TOF. Our analysis calls into question the validity of traditional ICD implantation guidelines in this growing and diverse patient population.