Repair versus replacement for ischemic mitral regurgitation

Whether repair or replacement is the preferred approach to surgical correction of ischemic mitral regurgitation is debated.  The Cardiothoracic Surgical Trials Network previously reported 1-year results of a randomized study of these two approached and found no differences echocardiographic or clinical outcomes. This paper reports the 2-year echocardiographic and clinical outcome results from this randomized trial of 251 patients with severe ischemic mitral regurgitation.  At 2 years follow-up, there were no significant differences in mortality (19% after repair versus 23% after replacement; P=0.39). Compared with replacement, the rate of recurrence of moderate or severe mitral regurgitation was significantly higher following repair (58.8% versus 3.8%; P<0.001).  Although the rate of major adverse cardiovascular events did not differ between the groups (42.1% in the repair group versus 42.4% in the replacement group), there were more serious heart failure events following repair (24.0 per 100 patient-years vs. 15.2 per 100 patient-years, P=0.05) and no significant difference in the rate of bleeding events between the two groups (3.5% in the repair group versus 5.3% in the replacement group; P=0.41).

Conclusions

In this study of mitral valve replacement versus repair for ischemic mitral regurgitation, no differences were observed in left ventricular remodeling or mortality at two years of follow-up.  However, there are significant differences in durability with much higher rates of severe mitral regurgitation following repair. The issue of durability as it relates to clinical outcomes will be important to monitor in continued follow-up of this study population.

Summarized by Hussain Contractor and Steven M. Bradley

Goldstein D, Moskowitz AJ, Gelijns AC, Ailawadi G, Parides MK, Perrault LP, Hung JW, Voisine P, Dagenais F, Gillinov AM, Thourani V, Argenziano M, Gammie JS, Mack M, Demers P, Atluri P, Rose EA, O’Sullivan K, Williams DL, Bagiella E, Michler RE, Weisel RD, Miller MA, Geller NL, Taddei-Peters WC, Smith PK, Moquete E, Overbey JR, Kron IL, O’Gara PT, and Acker MA. Two-Year Outcomes of Surgical Treatment of Severe Ischemic Mitral Regurgitation. N Engl J Med. 2015 Nov 9. [Epub ahead of print]