BACKGROUND A recently introduced tricuspid annuloplasty ring, the MC(3) ring, has a 3-dimensional form that is designed to remodel the tricuspid valve annulus. The aim of this study was to investigate its clinical performance. RESULTS From December 2004 to April 2008, 103 patients underwent tricuspid annuloplasty using the MC(3) ring (mean age, 52+/-13 years; 63.6% women). The average preoperative tricuspid regurgitation (TR) grade was 2.5+/-0.8, and the mean preoperative systolic pulmonary artery pressure was 48.4+/-15.0 (24-88) mmHg; the mean follow-up was 26.7+/-11.2 (0-52) months. One patient died after surgery (1.0%), because of cor pulmonale. No MC(3) ring-related complications, such as, atrioventricular block, ring dehiscence or thromboembolism, were encountered. Predischarge echocardiography showed a significant decrease in the TR grade (2.5+/-0.8 to 0.8+/-0.8, respectively; P<0.001). After a median 15 months, the mean TR grade was stable (0.9+/-0.8). The mean systolic pulmonary artery pressure was also lower than its preoperative value (33.9+/-7.9 vs 48.4+/-15.0 mmHg, respectively; P<0.001). CONCLUSIONS The MC(3) ring provides good mid-term clinical and echocardiographic results for TR. However, long-term follow-up is mandatory to confirm the stability of this procedure.