Residual root fate after aortic surgery in bicuspid aortic valve with right-to-left fusion: A comparative risk analysis

Abstract

Background and aim: Although bicuspid aortic valve (BAV) anatomy might influence aortic aneurysm development, BAV-related root involvement still lacks standardized surgical management. We aimed to evaluate late clinical outcomes and risk factors for root dilation after proximal aortic replacement in patients with BAV and right-left fusion (RL-BAV).

Methods: Clinical and echocardiographic data of all patients with intraoperative RL-BAV who underwent ascending aortic replacement with or without noncoronary sinus (NCS) replacement (Groups 1 and 2, respectively) between 1999 and 2017, were retrospectively revised. A multivariable analysis assessed hazard factors for root dilation during follow-up (FU).

Results: Of 206 surgeries performed (M 81%; age: 57 ± 13 years, EuroSCORE II: 2.7 ± 1.9%), 79 (38%) required NCS replacement. One hundred fifty-seven patients (76%) underwent aortic valve replacement (with aortic regurgitation predominating in Group 1, p = .04). The preoperative aortic root was larger in patients requiring NCS replacement (43.3 ± 5.1 vs. 39.2 ± 4.8 mm, p < .001). At a median FU time of 7 years (interquartile range: 4-10), no residual root dissections occurred, and only two patients (belonging to Group 2) required redo root surgery. Preoperative mild aortic regurgitation and aortic root diameter >35 mm at discharge were risk factors for root dilation >40 mm at FU (p = .02). Aortic root did not dilate over time, irrespective of NCS replacement (p = .06).

Conclusions: Aortic root in patients with RL-BAV undergoing ascending aortic replacement (±NCS replacement) does not significantly dilate over time, even if patients with preoperative aortic regurgitation and postoperative root more than 35 mm might require more surveillance.

Keywords: aorta and great vessels; aortic root; aortic surgery; bicuspid aortic valve.

Figure 1

Surgical image of the noncoronary sinus replacement technique: first, the bicuspid valve is exposed and its anatomy is defined (LC, left‐coronary cusp; NC, noncoronary cusp; RC, right coronary cusp) (A); the Dacron prosthesis is prepared and sutured starting from the noncoronary sinus (B and C)

Figure 2

CONSORT flow diagram showing inclusion and exclusion criteria of this study

Figure 3

Cumulative incidence curve for cardiac reoperations at follow‐up between Group 1 (ascending aortic replacement extended to the noncoronary sinus, red) and Group 2 (supracoronary ascending aortic replacement, green), with patients at risk at follow‐up. There was not a significant difference between the two cohorts (p = .42)

Figure 4

Echocardiographic aortic root diameter over follow‐up time in Group 1 (ascending aortic replacement extended to the noncoronary sinus, blue color) and Group 2 (supracoronary ascending aortic replacement, red color). Dots represent the observed root diameters at follow‐up, lines are an estimation of the residual root fate after surgery. Aortic root diameter slowly increases by 0.46 mm/year (95% confidence interval [CI]: −0.08 to 1.01) (p = .09) in Group 1, and by −0.01 mm/year (95% CI: −0.29 to −0.27) (p = .95) in Group 2. According to a linear mixed model, the estimated progression rate in Group 1 versus Group 2 is not significant (p = .06)