Patients undergoing mitral valve replacement had a lower risk of regurgitation and heart failure–related adverse events at 2 years than those undergoing valve repair, according to the results of a trial presented at the American Heart Association scientific sessions and published simultaneously in the New England Journal of Medicine.
The results of the trial appear to associate mitral valve replacement with clinical advantages over mitral valve repair after 2 years of follow-up. However, replacement held no significant advantages over repair in the primary endpoint of left ventricular end-systolic volume index (LVESVI) or in overall survival, said Dr. Daniel Goldstein of the department of cardiothoracic surgery at Montefiore Medical Center, New York.
In the trial conducted by the Cardiothoracic Surgical Trials Network (CTSN), 251 patients with chronic severe ischemic mitral regurgitation were randomly assigned to undergo surgical repair of the mitral valve or to receive a mitral valve replacement with a prosthetic and procedure selected at the discretion of the surgeon.
In addition to the primary endpoint of LVESVI, the two approaches were also compared for survival, regurgitation recurrence, and heart failure events.
At 2 years, the mean change from baseline in LVESVI, a measure of remodeling, did not differ significantly between the repair and replacement arms (–9.0 vs. –6.5 mL/m2, respectively). In addition, although the 2-year mortality rate was numerically lower in the repair arm relative to the replacement arm (19% vs. 23.2%, respectively), it was also not statistically different (P = .39).
However, the rate of recurrence of moderate or severe mitral regurgitation favored replacement over repair and was significant (3.8% vs. 58.8%, respectively; P less than .001). In addition, the rate of cardiovascular readmissions was significantly lower in the replacement group (P = .01).
For those in the repair group, there were significant trends for more serious adverse events related to heart failure (P = .05) and for a lower quality of life improvement (P = .07) on the Minnesota Living With Heart Failure questionnaire. There were no significant differences in rates of all serious adverse events or overall readmissions.
All of the differences between groups observed at 2 years amplify differences previously reported after 12 months (N Engl J Med. 2014 Jan 2;370[1]:23-32). For example, the difference in the rate of moderate to severe regurgitation favoring replacement over repair was already significant at that time (2.3% vs. 32.6%, respectively; P less than .001), even though the mortality rates were then, as now, numerically lower in the repair group versus the replacement group (14.3% vs. 17.6%, respectively; P = .45).
Dr. Goldstein reported no relevant financial relationships.