Subcutaneous array with active can implantable cardioverter defibrillator configuration: a follow-up study.

BACKGROUND

Novel nontransvenous implantable cardioverter defibrillator (ICD) configurations are sometimes required for small children and children with complex congenital heart disease at risk for sudden death. Mid- to long-term follow-up of these nontraditional implant techniques is not well known. We assessed the mid-term performance of a subcutaneous lead technique used in our practice.

METHODS

Between July 2002 and November 2003, 4 patients (age 2.1-8.5 years, weight 13-33.3 kg, height 90-126.7 cm) received an ICD with a single-finger (n = 3) or 2-finger (n = 1) subcutaneous array with an active abdominal can and epicardial pace/sense lead. The subcutaneous tunnel was created via a subxiphoid incision using a tunneling tool within a sheath along the seventh intercostal space and extended posterior to the spine. Diagnoses included long QT syndrome (n = 2), idiopathic ventricular fibrillation (n = 1), and idiopathic dilated cardiomyopathy (n = 1). Implantable cardioverter defibrillator indications included syncope (n = 2) and cardiac arrest (n = 2).

RESULTS

Mean follow-up was 22.3 +/- 13.9 months. During follow-up, 1 patient underwent heart transplantation and the other 3 patients underwent generator replacement secondary to a manufacturer's advisory. There was 1 appropriate and successful shock for ventricular fibrillation. This patient experienced a second episode of ventricular fibrillation that the ICD discharge failed to terminate. The arrhythmia spontaneously resolved. There were no inappropriate shocks. There was 1 instance of false detection of ventricular fibrillation because of intermittent T wave oversensing but therapy was not administered. There were no infections, lead fractures, or other complications during follow-up.

CONCLUSION

This novel nontransvenous ICD configuration can be used safely in a select group of pediatric patients and allows for the applicability of this life-saving technology to small children at high risk for sudden cardiac death.