Comparative analysis of mid-term outcomes of Rigid and NeoRing support rings in mitral regurgitation surgery: a prospective randomized trial

Abstract

Highlights. For the first time, as part of a prospective randomized study, a comparative assessment of the mid-term results of mitral valve annuloplasty using a new biological NeoRing ring (CJSC NeoKor, Kemerovo) and a RIGID ring (CJSC NPP MedInzh, Penza) in patients with connective tissue dysplasia was carried out. Predictors of the conversion of sinus rhythm to atrial fibrillation and residual mitral insufficiency in the medium-term follow-up period were determined.Aim. To analysis and compare mid-term results of mitral valve annuloplasty conducted using NeoRing и RIGID rings.Methods. From November 2019 to March 2022, 62 patients with mitral valve (MV) dysplasia underwent MV annuloplasty using NeoRing semi-rigid rings (CJSC NeoKor, Kemerovo, n = 31) and rigid RIGID rings (CJSC NPP MedInzh, Penza, n = 31). There were no differences between the groups at baseline.Results. Two deaths were registered during inpatient treatment in the RIGID group. Both devices showed a satisfactory outcome during inpatient treatment in the form of restoration of MV function (p<0.001) and the frequency of detected maximum residual mitral regurgitation (MR) up to grade 1 in the NeoRing group 9.7% and in the RIGID group 29%, respectively, no statistically significant intergroup differences were noted (p = 0.292). After 12 months, freedom from ≥2 grade MR in the NeoRing group was 93.5% and 77.4% in the RIGID group (p = 0.147). In the RIGID group, patients had higher values of the transvalvular mitral diastolic gradient – PAV 3.70 [3.00–4.40] mm Hg vs. NeoRing group 2.3 [2.05–2.85] mmHg (p<0.001), as well as a higher transvalvular flow rate – VAV 79 [71–94] cm/sec vs. 70 [64–79] cm/sec (p = 0.017). The analysis of the achievement of composite primary endpoint (recurrence of ≥2 grade MR, MACCE, new onset arrhythmias, reoperations) by the device was carried out. The composite endpoint rate in the RIGID group was 3.067 times higher compared to the NeoRing group, odds differences were statistically significant (p = 0.037, 95% CI: 1.053–8.934).Conclusion. The outcome of MV annuloplasty conducted using rigid and semi-rigid rings revealed no significant differences in long-term survival and recurrence of MR between groups. Given the statistically significant difference in achieving the combined endpoint, lower inpatient and long-term indicators of transmitral pressure gradient, and a positive effect on cardiac chambers reverse remodeling, it was concluded that the use of semi-rigid NeoRing rings for MV annuloplasty when performing valvepreserving operations for connective tissue dysplasia is preferable.