Predictors of Aortic Root Dilatation in Tetralogy of Fallot Patients

Tetralogy of Fallot (TOF) occurs in approximately 3 to 5 of every 10,000 live births and is the most common cyanotic congenital heart defect and it exhibits four main features. These features are pulmonary stenosis, right ventricular hypertrophy, overriding aorta and ventricular septal defect. Moreover, since the survival of patients with congenital heart diseases has improved significantly in recent decades, long-term complications should be monitored cautiously. One of these complications is aortic root dilatation, attributed to increased and altered flow through the overriding aorta and an uneven sharing of conotruncal tissue between the aorta and pulmonary artery, particularly in patients who have not undergone early repair. Despite the concern that TOF patients may harbor aortopathy that can lead to aortic regurgitation, aortic aneurysms, and, potentially, aortic dissection, the scope of the problem remains uncertain. Prevalence estimates of aortic root dilatation have ranged from 15% to 87% with the use of various criteria. Moderate to severe aortic regurgitation (AR) has also been reported in up to 12.5% of adults with TOF and dilated aortic roots. The incidence of aortic dissection and surgical intervention remains unknown. Moreover, features associated with aortic dilatation are not fully understood. Therefore, correlating and predicting vulnerable patients and identifying possible risk factors for aortic root dilatation in TOF patients, will enable more cautious follow-up and earlier intervention, thus decreasing possible morbidity and mortality.