Aortic annulus does not dilate over time after aortic root remodeling with or without annuloplasty

Abstract

Objective: The lack of annular stabilization is the drawback of aortic root remodeling, and recently the addition of annuloplasty has been proposed. Limited data, however, exist on late annular size after remodeling. We studied annular size over time.

Methods: In 241 patients (53 ± 16 years) annular size was determined preoperatively (T0), before discharge (T1), and at least 2 years after remodeling (T2, 54 ± 27 months) with (n = 52) or without external suture annuloplasty. Seventeen patients had Marfan syndrome (7%), 100 a bicuspid valve (41%), and 22 acute dissection (9%). Mean graft size was 25.2 ± 1.3 mm, and annuloplasty size 24.3 ± 1.4 mm.

Results: Annular size was significantly reduced after repair and remained stable over time (T0: 27.4 ± 3.0 mm, T1: 24.2 ± 2.5 mm, T2: 24.2 ± 2.6 mm). After propensity-score matching (n = 33 each), baseline annular size was similar (with annuloplasty vs without: 28.7 ± 4.1 mm vs 27.8 ± 2.8 mm). Annular reduction was less effective without annuloplasty (23.9 ± 2.0 mm vs 25.6 ± 2.2 mm, P < .01); size was identical at follow-up (23.8 ± 2.2 mm vs 25.1 ± 2.5 mm, P = .03). After matching, freedom from annular size increase >10% at 4 years was 93 ± 5% without annuloplasty and 91 ± 9% with annuloplasty (P = .92). A linear mixed-effects model identified no significant effect of annuloplasty on annulus diameter change at T2 (P = .48). Era after 2004, Marfan syndrome, and smaller annulus diameter at discharge were the independent predictors for late annular expansion.

Conclusions: Aortic annulus rarely dilates over time after remodeling. In the case of annular dilatation, annuloplasty normalizes annular size and may prevent further dilatation by enhancing cusp coaptation. Even without annuloplasty, the aortic annulus becomes smaller compared with preoperative dimensions when aortic valve remains competent.

Keywords: annular reverse remodeling; annuloplasty; aortic annulus; aortic root remodeling; propensity-score matching.