Leaflet resection, loop implantation similarly effective in repair of posterior mitral leaflet prolapse, researchers report

Repair of posterior mitral leaflet prolapse with either leaflet resection or loop implantation appears similarly effective in the early postoperative course, though the loop technique may provide a longer line of leaflet coaptation and may therefore be more durable, according to data from a recent study. For the study, 129 patients with severe mitral regurgitation (MR; mean MR grade of 3.4) underwent minimally invasive mitral valve surgery through a right lateral mini-thoracotomy....

Repair of posterior mitral leaflet prolapse with either leaflet resection or loop implantation appears similarly effective in the early postoperative course, though the loop technique may provide a longer line of leaflet coaptation and may therefore be more durable, according to data from a recent study.

For the study, 129 patients with severe mitral regurgitation (MR; mean MR grade of 3.4) underwent minimally invasive mitral valve surgery through a right lateral mini-thoracotomy. Posterior mitral leaflet prolapse was evident in all the subjects. The defects were repaired with either leaflet resection or implantation of premeasured polytetrafluoroethylene (PTFE) neochordae (loop technique) according to preoperative randomization assignments. Crossover was allowed if the surgeon deemed it medically necessary.

Successful mitral valve repair was accomplished in all patients; each subject also received an annuloplasty ring. Leaflet resection was performed in 53 patients and the loop technique in 69, among whom a mean of 3.2 loops were implanted on the P2 segment with a mean loop length of 13.3 mm. Overall, 9 patients crossed over from resection to loops and 3 patients crossed over from loops to resection.

Both groups demonstrated significant postoperative decreases in the mean MR grade (P<.001). Both groups also showed significant postoperative alterations in left ventricular ejection fraction (LVEF), left atrial size, left ventricular volume, mitral valve orifice area, and transvalvular gradients and velocities, though there were no significant between-group differences in any of these outcomes.

However, patients who underwent the loop technique had a significantly longer line of coaptation than patients who underwent resection (7.6 mm vs 5.9 mm; P=.03).

"Although it may be postulated that a longer line of coaptation may also be protective in patients with myxomatous mitral valve disease, longer follow-up will need to be performed to answer this question," the authors wrote.

Additionally, there were no significant between-group differences in the rates of early postoperative complications, including reoperation for bleeding and acute renal failure necessitating hemodialysis. However, there were 2 perioperative deaths in the loop group (1 due to massive pulmonary embolism and 1 due to acute right heart failure) compared with 0 deaths in the resection group.

Likewise, upon transthoracic echocardiography performed 6 months and 1 year after surgery, there were no significant between-group differences in LVEF, MR grade, mitral valve orifice area, or transvalvular velocities or gradients.

"This study showed that the use of PTFE neochordae (loop technique) with preservation of the posterior leaflet compares well with standard leaflet resection for the treatment of posterior mitral valve prolapse in the early postoperative course," the authors concluded. "Both techniques resulted in good echocardiographic outcomes with low rates of morbidity and mortality." (Falk V, et al. J Thorac Cardiovasc Surg 2008;136:1200-1206.)