Introduction

Tetralogy of Fallot (TOF) is the most common cyanotic heart defect. Repair of TOF, first performed over half a century ago, is one of the great success stories of congenital heart surgery.[1] The goals of complete surgical repair of TOF include elimination of intracardiac shunting and relief of right ventricular (RV) outflow tract (OT) obstruction. Pulmonary regurgitation (PR) is a nearly constant feature of repaired TOF and was originally thought to be a benign[2]; however, long-term studies have shown that chronic PR will predictably result in right ventricular dilatation, biventricular dysfunction, arrhythmias, worsening exercise intolerance, and sudden death (Figure 1).[3],[4],[5] Proper timing and technique of pulmonary valve replacement (PVR) is essential to maintain the long-term survival and quality of life of individuals with TOF.[6]

Figure 1

Long-term survival curve of 490 early survivors of repair of TOF. The curve shows 2 different phases that are distinct. The early, low risk phase lasts 25 years; thereafter, the risk increases significantly. Mortality risk (r) per year, as a linearized number, is calculated for each phase.