Abstract 12103: Vascular Function Affects Aortic Root Dilatation in Patients After Fontan Procedure

Abstract

Introduction: It is well known that, in patients with congenital heart disease, such as Tetralogy of Fallot, aortic root dilatation may gradually progress. Similar phenomenon also occur in patients with single ventricle circulation. However, the factors associated with aortic dilatation in these patients are still unknown. Hypothesis: We assessed the hypothesis that vascular function associated with the aortic root dilatation after Fontan procedure. Methods: Between July 2013 and April 2016, sixty-one patients who underwent the Fontan procedure (age, 12.8–55.8 years; median age, 23.2 years; postoperative duration, 8.2-31.3 years; median postoperative duration, 16.8 years) were enrolled. These patients were divided into 2 groups according to the presence or absence of aortic root dilatation and analyzed the relation between aortic root size and clinical profile, vascular function, hemodynamics, and neurohormonal factors. Aortic root dilatation was defined as observed/expected aortic root diameter >1.5 (aortic root dilatation, n=15, aortic root non-dilatation, n=46). Results and Conclusions: Age at Fontan procedure was significantly higher in the dilatation group than in the non-dilatation group (10.5±7.3 vs 5.3±4.0, P<0.01). FMD was significantly lower in the dilatation group than in the non-dilatation group (5.9±1.4 vs 8.3±2.3, OR 0.49, 95%CI 0.28-0.74, P<0.0001). Pulse wave velocity (PWV) was significantly higher in the dilatation group than in the non-dilatation group (1081±277 vs 943±140, P<0.05). Although hemodynamic variables and neurohormonal factors was not associated with aortic root size, pulmonary atresia was associated with aortic root dilatation (OR 5.43, 95%CI 1.55-20.18, P<0.01). In the multivariate analysis, impaired FMD had a close association with aortic dilatation (OR 0.45, 95%CI 0.19-0.82, P<0.01). FMD showed a negative correlation between age at Fontan procedure, PWV and parameter β(age at Fontan procedure r: -0.56, p<0.0001, PWV r: -0.32, p<0.05, β r: -0.27, p<0.05). We concluded that, in patients after Fontan procedure, vascular dysfunction such as aortic stiffness occurred in the patients who underwent Fontan procedure at older age and may play a role in progressive aortic dilatation.