ORLANDO, Fla. — For patients with severe ischemic mitral regurgitation, 2-year rates of survival and left ventricular end-systolic volume index (LVESVI) were similar between mitral valve repair and mitral valve replacement procedures. However, mitral regurgitation occurred more frequently in the repair group, leading to increased rates of heart failure-related adverse events and cardiovascular admissions.
“There is no evidence-based guidance to say what we should do with regurgitation of the mitral valve: Should we repair it or should we replace it? And that, in essence, is the controversy here,” said Daniel Goldstein, MD, of the Montefiore Medical Center in Bronx, New York, who presented the results of the Cardiothoracic Surgical Trials Network (CTSN) at the American Heart Association Scientific Sessions.
According to Dr Goldstein, proponents of mitral valve repair state that the procedure is associated with lower morbidity and mortality compared with mitral valve replacement, and preserves the entire structure of the subannular/subvavular apparatus.
“The problem with [repair] is that it can lead to recurrent mitral regurgitation and even functional mitral stenosis if the ring is very small,” Dr Goldstein said at a press conference. “Mitral replacement, on the other hand, has a higher perioperative morbidity/mortality but provides a more durable correction of the recurrence. So wherein lies the balance between those 2 was the subject of this undertaking.”
The CTSN study included 251 patients with severe ischemic mitral regurgitation who were randomly assigned to receive either mitral valve repair (n=126) or mitral valve replacement (n=125). Dr Goldstein and colleagues followed patients for 2 years to determine clinical and echocardiographic outcomes.
The primary end point was change in LVESVI from baseline and the secondary end points were left ventricular size and function at other time points, mortality, recurrent mitral regurgitation, major adverse cardiac and cerebrovascular events (MACCE), serious adverse events, and quality of life.
At 2-year follow-up, patients who survived had a mean LVESVI of 52.6 ± 27.7 mL/m2 in the repair group vs 60.6 ± 39.0 mL/m2 in the replacement group.
Researchers reported that between groups, there was a comparable rate of mortality (repair, 19.0% vs replacement, 23.2%; P=.39), with most deaths occurring in the first year, and rank-based assessment of LVESVI after adjusting for death was also similar (z score= –1.32; P=.19).
In addition, moderate or severe mitral regurgitation recurred more frequently in the repair group (58.8% vs 3.8%; P<.001). Most of the recurrences were moderate (86%) as opposed to severe (14%), Dr Goldstein said.
Furthermore, rates of serious adverse events, MACCE, and overall readmissions did not significantly differ between groups. However, patients who underwent repair experienced more serious adverse events that were related to heart failure (P=.05) and cardiovascular readmissions (P=.01), whereas those in the replacement group showed a trend toward greater improvement on the Minnesota Living with Heart Failure questionnaire (P=.07).
“We believe that replacement provides a more durable correction for severe ischemic mitral regurgitation,” Dr Goldstein concluded.
Disclosures: Dr Goldstein serves as a consultant for/on the advisory board of HeartWare and Medtronic, and reports other financial disclosures with Thoratec and Sunshine Heart.
Goldstein D et al. LBCT.06Two-Year Clinical Update: CT Surgery Network Severe MR Trial. Two-Year Outcomes following Mitral Valve Repair or Replacement for Severe Ischemic Mitral Regurgitation. Presented at: American Heart Association Scientific Sessions; November 7-11, 2015; Orlando, FL.
- Goldstein D, Moskowitz AJ, Gelijins AC, et al; for the Cardiothoracic Surgical Trials Network. Two-year outcomes of surgical treatment of severe ischemic mitral regurgitation. N Engl J Med. 2015;doi:10.1056/nejmoa1512913.