Immediate and Mid-term Result of Restrictive Mitral Annuloplasty Using a Small Semi-rigid Ring

Objective: Though annuloplasty using a properly sized ring has been advocated in degenerative mitral regurgitation, restrictive annuloplasty using a down-sized ring is widely used in ischemic mitral regurgitation. We investigated the outcome of restrictive annuloplasty using a small (24- or 26-mm) ring in mitral regurgitation irrespective of the etiology.

Methods: Nineteen patients underwent a restrictive annuloplasty using a 24-mm (n = 8) or 26-mm (n = 11) semi-rigid ring. The etiology included degenerative in 13 patients, ischemic in 3, endocarditis in 2, and congenital in 1. Body surface area of the patients implanted with the 24-mm ring was 1.40 ± 0.16 and 1.60 ± 0.18 m(2) for the 26-mm ring. Fifteen patients had 3+ or 4+ mitral regurgitation preoperatively.

Results: Two patients were converted to valve replacement for residual mitral regurgitation during the operation. One operative mortality associated with infection was observed. Echocardiogram at 29.4 ± 14.2 months postoperatively demonstrated mitral valve area of 2.0 ± 0.6 cm(2) for 24-mm ring and 2.2 ± 0.5 cm(2) for 26-mm ring with indexed mitral valve area of 1.4 ± 0.4 cm(2)/m(2) for both groups, and no mitral regurgitation more than 2+. Transmitral mean pressure gradient on rest was 4.7 ± 2.1 mmHg at last follow up. New York Heart Association class improved from 2.2 ± 0.7 to 1.2 ± 0.2 after the operation. No late death or reoperation was observed during the follow-up of 31.0 ± 15.0 months.

Conclusions: Restrictive mitral annuloplasty using a small ring provided acceptable early and midterm results in patients with body surface area around 1.5 cm(2) without Barlow pathology. Restrictive annuloplasty may be another technical aspect to avoid valve replacement.