- 21% of study patients had recurrent mitral regurgitation at one year after surgery
- The left ventricular end systolic dimension/ring size ratio predicts recurrent mitral regurgitation
- The left ventricular end systolic dimension/ring size ratio could be a method for identifying patients at high-risk
With recurrent mitral regurgitation occurring in up to 30% of patients one year after surgery for mitral valve repair and up to 60% after two years, it is critical for clinicians to have a method to decide which patients should receive mitral valve repair or mitral valve replacement. One recent analysis of two randomized clinical trials provides one possibility for that utility.
In an article in Circulation, researchers led by Judy Hung, MD, of the Massachusetts General Hospital Corrigan Minehan Heart Center, found that a mismatch between left ventricular size and mitral valve ring may help clinicians to decide if mitral valve replacement would be more efficacious than mitral valve repair in patients with the mismatch.
The researchers analyzed data on 214 patients (mean age 66 years, 67% men) who participated in the two clinical trials, as noted in the New England Journal of Medicine, (one and two) conducted by the Cardiothoracic Surgical Trials Network. These patients had complete transthoracic echocardiogram one year after ring annuloplasty. Of the 214 patients, 90% underwent coronary artery bypass graft (CABG) along with mitral valve repair surgery.
The researchers measured the left ventricular/mitral valve ring discrepancy as the ratio of left ventricular end diastolic dimension and left ventricular end systolic dimension to the implanted ring size. Of the 214 patients, 45 (21%) had moderate to greater mitral regurgitation one year after ring annuloplasty. The patients with recurrent mitral regurgitation weighed less than patients who did not and tended to have lower body surface areas. Also, researchers found that the prevalence of atrial fibrillation, previous CABG and percutaneous coronary intervention was higher in patients with recurrent mitral regurgitation.
In univariable analyses, the researchers also found that the left ventricular end systolic dimension and the left ventricular end systolic dimension/ring size ratio significantly predicted one-year recurrence of mitral regurgitation. The odds ratio per 10 mm increase in left ventricular end systolic dimension came to 1.62 (P=0.02) and the odds ratio per 0.5 increase in left ventricular end systolic dimension/ring size ratio came to 2.15 (P=0.007).
After adjustment for age, sex, baseline severity of disease and left ventricular ejection fraction, the left ventricular end systolic dimension/ring size ratio still predicted a higher risk of recurrent mitral regurgitation (odds ratio 2.20, P=0.038).
The researchers point out that the left ventricular end systolic dimension/ring size ratio could be a utility to identify patients who would be at high risk of recurrent mitral regurgitation after mitral valve ring annuloplasty and guide surgical decision-making as to whether repair or replacement should be performed.
Refer a patient to the Massachusetts General Hospital Corrigan Minehan Heart Center