American Board of Internal Medicine (ABIM) Certification Practice Exam

What is the most common structural disorder following tetralogy of Fallot repair?

1. Mitral stenosis

2. Aortic regurgitation

3. Pulmonary regurgitation

4. Tricuspid regurgitation

The correct answer is: Pulmonary regurgitation

Pulmonary regurgitation is indeed the most common structural disorder that arises after tetralogy of Fallot (ToF) repair. This complication typically results from the surgical correction of the conotruncal anomaly associated with ToF, which includes the infundibular (outflow tract) obstruction, ventricular septal defect, and aortic override. During the repair, particularly if a transannular patch is used to alleviate the right ventricular outflow tract obstruction, the integrity of the pulmonary valve is often compromised. This can lead to a deficiency in proper closure of the valve during diastole, allowing regurgitation of blood back into the right ventricle from the pulmonary artery. The increased pressure and volume load from this regurgitant flow can subsequently lead to right ventricular dilation and dysfunction over time. While tricuspid regurgitation and aortic regurgitation can also develop postoperatively, they are less prevalent compared to pulmonary regurgitation. Mitral stenosis is not a common concern following the repair of tetralogy of Fallot as it does not directly relate to the structural alterations made during the surgical correction of the other defects. Understanding these connections helps in recognizing the potential long-term complications in patients who undergo repair