Pulmonary insufficiency is the nexus of late complications in tetralogy of Fallot.

The number of adults with tetralogy of Fallot now exceeds the number of children with the disorder due to childhood surgical successes. After surgical repair, however, most patients are left with pulmonary regurgitation that, over time, results in right ventricular volume overload, enlargement, and dysfunction. Usually well tolerated for 20 years or more, ongoing pulmonary insufficiency is at the core of late complications that include right ventricular failure, exercise intolerance, atrial and ventricular arrhythmias, and sudden death. Though late pulmonary valve replacement appears to attenuate this risk, prostheses have a finite life span. Thus, the timing of surgery must be carefully considered, weighing the up-front risks of surgery and possible repeat surgery against the risk of ongoing pulmonary regurgitation.