Interventional Electrophysiology in Patients With Congenital Heart Disease

Abstract

“The treatment of congenital heart disease is unsatisfactory. As a rule, nothing can be done to improve patients symptomatically; in some instances digitalis may be of help.” — —L. Emmett Holt, MD, 1933 On August 26, 1938, Dr Robert Gross performed the first successful surgery for a congenital heart defect by closing a patent ductus arteriosus in a 7-year-old girl. The event marked the beginning of an interventional approach to congenital heart disease (CHD) that forever banished the sort of pessimism expressed by Dr Holt in his classic pediatric textbook only 5 years earlier.1 Subsequent diagnostic and operative innovations ultimately led to surgical solutions for nearly all anatomic heart defects, allowing the vast majority of infants born with CHD in the modern era to survive into adulthood. However, improved hemodynamic longevity has exposed alternate sources of morbidity and mortality for this population, central among which are cardiac rhythm disorders. In some instances, arrhythmias are intrinsic to the CHD lesion itself, but in most cases, they arise as an unintended consequence of prior corrective surgery whenever patches and suture lines function in conjunction with hypertrophy and fibrosis to create the substrate for reentrant tachycardias. It is fortunate that improved understanding of rhythm abnormalities in CHD has coincided with the emergence of interventional electrophysiological techniques. Catheter ablation, arrhythmia surgery, pacemakers, and implantable defibrillators have now become indispensable treatment options for this group. It is the purpose of this article to review the application of these tools to CHD with an emphasis on unique technical challenges. Congenital heart defects occur in roughly 0.8% of live births, and in 30% to 50% of cases, the malformations are severe enough to warrant ≥1 surgical procedures during early childhood.2 Arrhythmia mechanisms vary according to the underlying anatomic defect and method of surgical repair. The …