Aortic Root Dilatation in Adults With Surgically Repaired Tetralogy of Fallot: A Multicenter Cross-Sectional Study

Study Questions:

What are the prevalence and predictors of aortic root dilatation in adults with repaired tetralogy of Fallot (TOF)?

Methods:

A multicenter cross-sectional study was performed by the Alliance for Adult Research in Congenital Cardiology. Echocardiographic parameters of 474 adults with TOF or pulmonary atresia with ventricular septal defect were reviewed. The aortic root measurements were reported both as absolute values and as a calculated observed-to-expected ratio, taking into account age and body surface area. Aortic root dilatation was considered present if the observed-expected ratio was >1.5.

Results:

The aortic root dimension was ≥40 mm in 28.9% of patients. In multivariate analysis, the only independently associated variable was male sex (odds ratio, 4.48; 95% confidence interval, 26.9%-30.9%). The prevalence of an observed-to-expected ratio of >1.5 was 6.6%. On univariate analysis, this was associated with pulmonary atresia and severe aortic insufficiency, although no independent predictors were found on multivariate analysis. Arch sidedness was not associated with root dimension. Moderate to severe aortic regurgitation occurred in 3.5% of patients.

Conclusions:

Although almost 30% of adults with TOF have aortic root diameters ≥40 mm, the prevalence of aortic root dilation, as defined by an indexed ratio of observed-to-expected values, is low.

Perspective:

Aortic root dilation has been frequently reported in adults with TOF, although aortic dissection appears to be exceedingly rare and has occurred in the setting of extremely dilated aortas (70 mm and greater). This study confirms that aortic dilation, as defined by aortic measurement ≥40 mm, is relatively common; the use of indexed values as described by Roman et al. (Roman MJ, et al., Am J Cardiol 1989;64:507-12) results in a much lower prevalence. Although aortic dimension should continue to be followed in adults with TOF, this study is reassuring that the prevalence of significant aortic dilation may not be as high as previous estimates.

Keywords: Tetralogy of Fallot, Pulmonary Atresia


< Back to Listings