Implantable Cardioverter-defibrillators in Adult Congenital Heart Disease

Abstract

With improved surgical techniques and medical therapies, many patients who are born with complex congenital heart defects are now living well into adulthood. As these patients age, an increasingly common cause of mortality is sudden cardiac death (SCD) from ventricular tachyarrhythmias. The implantable cardioverter-defibrillator (ICD) is a therapy with the ability to prevent some of these deaths; however, there are many diagnostic and technical challenges that remain in the congenital heart disease (CHD) population. We performed a literature review, searching PubMed for articles that examined the role of ICDs in CHD. We herein present the evidence for when to place an ICD in CHD patients, stratified by subtype as relevant. Then, we discuss the technical challenges and complications that are unique to this patient population. We conclude that, despite active work in the area, more research is needed given the small event rates and clinical variability within CHD populations.

Keywords: Congenital heart defect; implantable cardioverter-defibrillator; sudden cardiac death; tetralogy of Fallot; transposition of the great arteries.

Figure 1:

A patient with dextrocardia, atrial septal defect, ventricular septal defect, coarctation of the aorta, and aortic stenosis following mechanical aortic valve implantation with postsurgical complete heart block and subsequent dual chamber biventricular permanent pacemaker implantation. The patient later required an ICD for sustained symptomatic VTA seen on an implantable loop recorder. A right-sided subcutaneous device was chosen given the complexity of existing intravascular hardware, anatomic malalignment concerning for poor transvenous shock vector, and existing venous occlusions.