Implantable cardioverter-defibrillators in adults with congenital heart disease: a systematic review and meta-analysis

Abstract Aims Sudden cardiac death is a major cause of mortality in adult congenital heart disease (ACHD) patients. The indications for implantable cardioverter-defibrillator (ICD) implantation in ACHD patients are still not well established. We aim to systematically review the literature on indications and outcome of ICD implantation in ACHD patients. Methods and results We performed a comprehensive search in EMBASE, MEDLINE, and Google Scholar to identify all studies on ICD implantation in ACHD patients. We used random effects models to calculate proportions and 95% confidence intervals. Of 1356 articles, 24 studies with 2162 patients were included, with a mean follow-up of 3.6 ± 0.9 years. Half of patients had tetralogy of Fallot. Mean age at implantation was 36.5 ± 5.5 years old and 66% was male. Implantable cardioverter-defibrillators were implanted for primary prevention in 53% (43.5–62.7). Overall, 24% (18.6–31.3) of patients received one or more appropriate ICD interventions (anti-tachycardia pacing or shocks) during 3.7 ± 0.9 years: 22% (16.9–28.8) of patients with primary prevention in 3.3 ± 0.3 years and 35% (26.6–45.2) of patients with secondary prevention in 4.3 ± 1.2 years. Inappropriate shocks occurred in 25% (20.1–31.0) in 3.7 ± 0.8 years and other, particularly lead-related complications in 26% (18.9–33.6) of patients in 3.8 ± 0.8 years. All-cause mortality was 10% during 3.7 ± 0.9 years. Conclusions In ACHD, remarkably high rates of appropriate ICD therapy were reported, both in primary and secondary prevention. Because of the young age and lower death rates, the cumulative beneficial effects are likely greater in ACHD patients than in acquired heart disease patients. However, considering the high rates of inappropriate shocks and complications, case-by-case weighing of costs and benefits, remains essential.