Implantable cardioverter-defibrillators in congenital heart disease

Sudden cardiac death is a leading cause of mortality in patients with congenital heart disease (CHD), such that implantable cardioverter-defibrillators (ICDs) are a critical component of care. Objectives of this review are to highlight recent advances regarding ICDs in CHD, with a focus on clinical indications, technical issues and solutions, and patient outcomes.

Evolving ICD indications in CHD are primarily derived from observational research or extrapolations from the general adult literature. Technical challenges to device implantation include obstructed vasculature or conduits, intracardiac shunts with their attendant risk for systemic thromboemboli, and lack of venous access to the heart. In selected patients, tailored epicardial systems may be considered that include subcutaneous, retrocardiac, and/or venous (e.g., azygous) coils. Alternatively, an entirely subcutaneous ICD may be a reasonable option in patients with no bradycardia or antitachycardia pacing indications. Long-term complications include inappropriate shocks, lead failure, reduction in quality of life, shock-related anxiety, and impaired sexual function.

Although ICDs undeniably save lives, challenges to applying this technology to patients with CHD include the paucity of evidence-based data to guide patient selection, technical challenges related to venous access, patient size, anatomic complexities, and a high rate of complications.