RING plus STRING Successful Repair Technique for Ischemic Mitral Regurgitation With Severe Leaflet Tethering

Background-Residual/recurrent mitral valve regurgitation is observed in 30% after undersized ring annuloplasty ( RING) for ischemic mitral regurgitation (IMR). RING addresses primarily annular dilatation but does not correct severe leaflet tethering attributable to papillary muscle (PM) displacement. We proposed adjunctive PM repositioning under transesophageal echocardiography (TEE) guidance in the loaded beating heart using a transventricular suture (STRING). Methods and Results-Patients with tenting height >= 10 mm were identified as high-risk patients for repair failure. In these patients (n=30, age 68 +/- 11 years, ejection fraction 37 +/- 14%), RING (partial, median 29 mm) was combined with the adjunctive STRING-technique. A Teflon-pledgeted 3-0-polytetrafluoroethylene-suture was anchored in the posterior PM via horizontal aortotomy, exteriorized through the aorto-mitral continuity, and tied in the loaded beating heart under TEE guidance. Tenting height (14 +/- 2 mm versus 6 +/- 1 mm, P<0.001) and tenting area (3.9 +/- 0.9 cm(2) versus 1.0 +/- 0.2 cm(2), P<0.001) decreased. The distance between pPM and aorto-mitral continuity decreased (44 +/- 4 mm versus 37 +/- 3 mm, P<0.001). Survival at 2 years was similar compared with a historical matched control-group (89% versus 73%, P=0.13), whereas freedom from MR>II was higher in the RING+STRING-group (94% versus 71%, P=0.01). End-diastolic (61.7 +/- 7.2 mm versus 54.8 +/- 9.2 mm, P<0.001) and end-systolic (48.5 +/- 8.5 mm versus 42.7 +/- 7.8 mm, P=0.002) ventricular diameters decreased in the RING+STRING-group but persisted in the control-group (60.4 +/- 7.8 mm versus 58.9 +/- 7.5 mm, P=0.38; 47.8 +/- 9.6 mm versus 48.3 +/- 9.5 mm, P=0.52). During follow-up (median 26 months) only 1 patient of the study-group required reoperation for degenerative MR, while 2 control-group patients underwent reoperation for recurrent functional MR. Conclusions-Our novel approach for IMR attenuates high risk of repair failure in patients with severe leaflet tethering and results in reverse remodeling. (Circulation. 2009; 120[suppl 1]: S85-S91.)