Current outcomes and treatment of tetralogy of Fallot

Abstract

Tetralogy of Fallot (ToF) is the most common type of cyanotic congenital heart disease. Since the first surgical repair in 1954, treatment has continuously improved. The treatment strategies currently used in the treatment of ToF result in excellent long-term survival (30 year survival ranges from 68.5% to 90.5%). However, residual problems such as right ventricular outflow tract obstruction, pulmonary regurgitation, and (ventricular) arrhythmia are common and often require re-interventions. Right ventricular dysfunction can be seen following longstanding pulmonary regurgitation and/or stenosis. Performing pulmonary valve replacement or relief of pulmonary stenosis before irreversible right ventricular dysfunction occurs is important, but determining the optimal timing of pulmonary valve replacement is challenging for several reasons. The biological mechanisms underlying dysfunction of the right ventricle as seen in longstanding pulmonary regurgitation are poorly understood. Different methods of assessing the right ventricle are used to predict impending dysfunction. The atrioventricular, ventriculo-arterial and interventricular interactions of the right ventricle play an important role in right ventricle performance, but are not fully elucidated. In this review we present a brief overview of the history of ToF, describe the treatment strategies currently used, and outline the long-term survival, residual lesions, and re-interventions following repair. We discuss important remaining challenges and present the current state of the art regarding these challenges.

Keywords: Congenital Heart Disease; Fallot; Outcomes; Survival; Tetralogy.

Figure 1.. Schematic overview of the defects seen in tetralogy of Fallot.

(1) Pulmonary stenosis. (2) Overriding aorta. (3) Malalignment ventricular septal defect. (4) Right ventricular hypertrophy. Modified from Englert et al. with permission from the publisher.

Figure 2.. Transventricular (left) and transatrial-transpulmonary (right) approach to tetralogy of Fallot (ToF) repair.

VSD, ventricular septal defect. Adapted from Bushman with permission from the publisher.

Figure 3.. Survival following tetralogy of Fallot (ToF) repair.

Each colored line represents a single study, and dots represent Kaplan–Meier survival estimates at different time points ^{, –} . Ninety-five percent confidence intervals, where published, are shown in vertical lines. Lines are colored according to surgical era.