Implantable Cardioverter-Defibrillator Therapy in Patients With Transposition of the Great Arteries: A Systematic Review of the Literature.

Background: Patients with a systemic right ventricle (sRV) due to transposition of the great arteries are known to have a particularly high risk of sudden cardiac death. Current guidelines issue a weak recommendation to consider primary prevention implantable cardioverter-defibrillator (ICD) implantation in patients with severe sRV dysfunction. This systematic review aims to ascertain factors that are associated with appropriate ICD therapy in patients with an sRV and primary prevention ICD, so that we can further refine selection criteria for implantation in this population. Methods: A systematic search of MEDLINE and Embase was performed to identify all studies that explored ICD therapies and associated clinical characteristics in patients with an sRV and primary prevention ICD from the inception of the databases until February 14, 2023. Results: A total of 11 articles were included in the final analysis. Among those with a primary prevention ICD, 23 (9.1%) had appropriate ICD therapies and 48 (19%) received inappropriate ICD therapies. Among those with appropriate ICD therapies, the most common reason for implantation was sRV dysfunction, followed by nonsustained ventricular tachycardia and ventricular tachycardia on a Holter monitor. Among those with a secondary prevention ICD, 15 (34.9%) received appropriate ICD therapies and 5 (11%) had inappropriate ICD therapies. Most inappropriate therapies were due to atrial tachyarrhythmias. Conclusions: sRV dysfunction was the most consistently reported risk factor for appropriate ICD therapy in our review. Effective treatment of atrial tachyarrhythmias remains a priority. Larger scale studies are required to develop and validate risk calculation in this population.