Subcutaneous implantable cardioverter defibrillator in complex adult congenital heart disease. Results from the S-ICD “Monaldi Care” registry

Implantable cardioverter defibrillators (ICD) are widely accepted therapy in congenital heart disease (CHD) patients at risk of life-threatening ventricular arrhythmias or sudden cardiac death (SCD). Initial experience with subcutaneous ICD (S-ICD) systems has shown a high efficacy. However, the use of S-ICD in complex ACHD (adult congenital heart disease) implies some specific considerations, as the safety for these patients in unknown and recommendations among physicians may vary widely. We review the data and studied the indications for S-ICD in complex ACHD and discuss its usefulness in clinical practice. From a large cohort of 297 patients enrolled in the S-ICD “Monaldi care” registry, that encompass all the patients implanted in the Monaldi Hospital of Naples, we considered 14 consecutive complex ACHD patients (aged 35.9 ± 16.7 years) who underwent S-ICD implant from February 2015 to June 2020. Mean follow-up was 23 ± 19.5 months. All the patients showed a good compliance to the device system with no complications (infections or skin erosions). Four patients (1 M/3F aged 38.2 ± 11.3) were listed for heart transplantation (HTX). Two of these underwent HTX, one died for refractory heart failure (HF) and one is still on the waiting list. There might be a conceivable benefit from an extended use of the S-ICD in selected patients with CHD, especially in those with life-treating ventricular arrhythmias and complex anatomy or patients awaiting HTX. S-ICD appears to be a safe alternative to a transvenous system when a transvenous ICD cannot be implanted and pacing is not required.