Results
A total of 165 patients were included during the study period, 48 patients (29.1%) had BAV, while TAV was found in 117 patients (70.9%). The demographics, clinical characteristics and perioperative outcomes are summarized in Table1. The mean diameter of aortic root at baseline was comparable between the two groups (33.3±4mm vs 33.6±4.4mm, p=0.717), but the mean diameter of ascending aorta at baseline was larger in BAV group than in TAV group (38±4.1mm vs 35.6±4.5mm, p=0.001, Fig. 1).
Follow-up data was obtained on all 165 hospital survivors. The median follow-up was 7 years, up to a maximum of 15 years, with no difference between BAV group and TAV group (P=0.883). During the follow-up, a total of 10 patients(6.1%) died, including 5 in the BAV group while 5 in TAV group(p=0.439) . The causes of late deaths were listed in Table 2. In the BAV group, there were 2 cardiac related death, 1 patient died of congestive heart failure, and 1 patient died of sudden cardiac death. In the TAV-group, there were 2 cardiac related death, 1 patient died of congestive heart failure and 1 patients suffered sudden cardiac death. In both groups, there were no late deaths due to aortic dissection or aortic rupture. The overall survival rate was 89% and 95.8% at 10 years postoperatively in BAV versus TAV groups (Plog rank=0.138, Fig. 2).
Only 1 patient suffered aortic dissection and underwent proximal aortic surgery during the follow up period. The patient, in the TAV-group, was diagnosed as ascending aortic dissection 5 years after the initial AVR procedure. The progression of the aortic root and ascending aorta between the initial AVR surgery and the proximal aortic surgery were 20mm and 18mm . No patient in the BAV-group required proximal aortic surgery.
During follow-up, there was no difference in progression of aortic root (1.3±4.7mm vs 0.3±4mm, p=0.225) and ascending aorta (0.8±4.7mm vs 0.6±3.5mm, p=0.821. Fig. 3). When demographic, clinical and echocardiographic variables were added to the unconditional model, The diameter of ascending aorta at baseline (p<0.001) was a significant predictor of progression in ascending aorta.