Bicuspid aortic valve repair using geometric ring annuloplasty: A first-in-humans pilot trial

Abstract

Objective: As bicuspid aortic valve (BAV) repair evolves, more effective annular reduction and stabilization could be advantageous. A geometric annuloplasty ring has been developed, and 2-year regulatory outcomes of a first-in-humans pilot trial are reported.

Methods: A prospective first-in-humans trial of BAV ring annuloplasty was completed in 16 patients. Patient age was 44.4 ± 11.3 (mean ± standard deviation) years, preoperative aortic insufficiency grade was 2.5 ± 1.0, New York Heart Association class 1.8 ± 0.4, and mean systolic gradient 13.4 ± 12.9 mm Hg. Three patients had Sievers type 0 BAV, 11 had type 1, and 2 were type 2. The Dacron-covered titanium rings had circular base geometry with 180° subcommissural posts and were implanted subannularly. Leaflets were reconstructed using plication/cleft closure, creating an effective height of ≥8 mm, even if modest gradients were induced.

Results: Mean pre-repair annular diameter was 28.6 ± 3.3 mm, and the average ring diameter was 22.3 ± 1.6 mm. All valves required leaflet plication/reconstruction; pericardium was avoided; and 7 patients had aortic replacement for aneurysms. No early mortalities or major complications occurred. Two patients required early prosthetic valve replacement for technical errors, and all were between 24-38 months' postoperative at follow-up. No late mortalities or valve-related complications occurred, and all patients reverted to New York Heart Association class I. Aortic insufficiency reduction was significant to grade 0.9 ± 0.5 at 2-years (P < .0001). Mean valve gradients were acceptable (13.3 ± 5.0 mm Hg at 2 years; overall P = .11) and tended to fall over time (P < .0001).

Conclusions: Geometric ring annuloplasty was safe and effective for BAV repair. AI reduction was significant, valve gradients were satisfactory, and clinical outcomes were excellent. Geometric ring annuloplasty could simplify and standardize BAV repair.

Keywords: AI, aortic insufficiency; AVR, aortic valve replacement; BAV, bicuspid aortic valve; aortic annuloplasty; aortic valve repair; bicuspid aortic valve.

Outcomes observed over 2 years after BAV repair using geometric ring annuloplasty.

Figure 1

A bicuspid aortic valve annuloplasty ring with circular base geometry and two 180° subcommissural posts.

Figure 2

Computed tomography angiograms of representative BAV repair cases before and after repair. Patient 1 has a Sievers type 0 BAV with nearly equal sinuses and leaflets. Patients 2 to 4 have left-right fusion Sievers type 1 valves with varying degrees of annular enlargement. Patient 5 has left-right fusion with 3 equal sinuses. A 21-mm pink circle is superimposed, as well as red dots in the areas of 180° commissures. At the mid-valve level after successful repair, notice the valve assumes more of a circular base geometry, with symmetrical 180° commissures. These features were incorporated into the ring design.

Video 1

A clinical video of all the techniques employed in this paper. Video available at: https://www.jtcvs.org/article/S2666-2507(20)30023-7/fulltext.

Figure 3

Technique of type 1 BAV repair. A, With exposure achieved by 6 commissural and aortic sutures, a cleft in the fused leaflet (yellow arrow) is evident, as well as a redundant and prolapsing nonfused noncoronary leaflet. B, Horizontal mattress sutures bury the ring posts into the subcommissural spaces (red arrow). C, After placing annular sutures around both sinus areas, the sutures are tied over fine Dacron pledgets, and one needle is passed laterally (green arrow) and tied again to laterally fixate annular sutures away from leaflets. D, After repair, the linear closure of the fused leaflet cleft is evident (blue arrow) along with several plications on the non-fused leaflet. Importantly, the effective heights, geometric heights, and free-edge lengths of the 2 leaflets are equal. BAV, Bicuspid aortic valve.

Figure 4

Time course of clinical and echocardiographic variables before and after BAV repair. In this analysis, the early repair failures were omitted, because their repairs were not available for assessment long term. The results, however, changed insignificantly if the 2 repair failures were included. A, Survival was excellent. B, All patients became asymptomatic. C, Average AI grade fell below 1+ and remained low. D, Mean valve gradients increased slightly immediately after annuloplasty, but overall, remained statistically unchanged by analysis of variance (P = .11). BAV, Bicuspid aortic valve; AI, aortic insufficiency; NYHA, New York Heart Association; SEM, standard error of the mean; ANOVA, analysis of variance; Scrn, screening data; Disch, discharge data.

Figure 5

Mean valve gradients for individual patients over time after repair. One third of patients had mean gradients in excess of 20 mm Hg at discharge, but they all improved to approximately 20 mm Hg or less at 2-years (P < .001 by analysis of variance of postrepair data only). BAV, Bicuspid aortic valve; ANOVA, analysis of variance; Preop, preoperative; Disch, discharge data.