Functionally Univentricular Heart and the Fontan Operation

Abstract

"The term "functionally univentricular heart" describes a spectrum of congenital cardiovascular malformations in which the ventricular mass may not readily lend itself to partitioning that commits one ventricular pump to the systemic circulation and another to the pulmonary circulation." The purpose of this article is to review patterns of practice and outcomes in the Congenital Heart Surgery Databases (CHSDBs) of the European Association for Cardio-Thoracic Surgery (EACTS) and the Society of Thoracic Surgeons (STS) in patients with functionally univentricular hearts undergoing the Fontan operation. We examined all index operations performed on patients with functionally univentricular hearts in the EACTS and STS-CHSDBs over 4 years from 2007 to 2010, inclusive. The most common diagnostic categories are hypoplastic left heart syndrome, tricuspid atresia, and double inlet left ventricle. The Fontan operation makes up 3.2% of all cardiac operations in the EACTS and STS-CHSDBs over 4 years from 2007 to 2010, inclusive. Of all the patients undergoing a Fontan procedure, 65.1% had an extracardiac Fontan, 21.5% had a lateral tunnel, and 5.8% had a Fontan revision or conversion (Re-do Fontan). In operations where fenestration status is known, 68.5% of the Fontan operations were fenestrated. During the four years of this analysis, only 5 patients had ventricular septation. Exclusive of Fontan revision or conversion (Re-do Fontan), all remaining Fontan operations had a discharge mortality of 2.3%. Fontan revision or conversion (Re-do Fontan) had a discharge mortality of 12.8%. The STS database is largest CHSDB in North America. The EACTS database is largest CHSDB in Europe. This review of data from EACTS and STS allows for unique documentation of practice patterns and outcomes. From this analysis, it is clear that patients with functionally univentricular hearts present a challenging problem; however, exclusive of Fontan revision or conversion (Re-do Fontan), the Fontan operation has a discharge mortality of 2.3%.