How does the use of polytetrafluoroethylene neochordae for posterior mitral valve prolapse (loop technique) compare with leaflet resection? A prospective randomized trial
Mitral valve surgery for posterior mitral leaflet prolapse consists mostly of leaflet resection, but implantation of premeasured polytetrafluoroethylene neochordae (ie, loops) is another option. The aim of this prospectively randomized trial was to determine how preservation of leaflet structure in combination with premeasured neochordae compares with the widely adopted technique of leaflet resection.
Methods
A total of 129 patients with severe mitral regurgitation, with a mean mitral regurgitation grade of 3.6 ± 0.6, underwent minimal invasive mitral valve surgery through a right lateral mini-thoracotomy. The mean age was 59.5 ± 12 years, 90 patients were male, the mean preoperative ejection fraction was 65% ± 8%, and the mean New York Heart Association functional class was 2.1 ± 0.7. Posterior mitral leaflet prolapse was diagnosed in all patients. Randomization was performed preoperatively, and crossover was allowed if the surgeon deemed it medically necessary. Crossover from resection to loops occurred in 9 patients, and crossover from loops to resection occurred in 3 patients.
Results
Mitral valve repair was accomplished in all patients (n = 129, 100%), and all patients received an annuloplasty ring. The mean number of loops implanted on the posterior mitral leaflet was 3.2 ± 0.9, with a mean length of 13.3 ± 2.2 mm. The mean duration of cardiopulmonary bypass was 135 ± 37 minutes and the mean aortic crossclamp time was 82 ± 26 minutes in all patients, with no significant difference between groups. Intraoperative transesophageal echocardiography showed a significantly longer line of mitral valve leaflet coaptation after implantation of loops (7.6 ± 3.6 mm) than after resection (5.9 ± 2.6 mm; P = .03). Thirty-day mortality was 1.6% for the entire group (2/129), with both deaths occurring in the loop group. Cause of death was massive pulmonary embolism in 1 patient and acute right heart failure in 1 patient. Early and mid-term echocardiographic follow-up revealed excellent valve function in the majority of patients, with no significant difference in mitral orifice area (3.6 ± 1.0 cm2 vs 3.7 ± 1.1 cm2, P = .4).
Conclusion
Both repair techniques for posterior mitral leaflet prolapse are associated with excellent results and appear comparable in the early postoperative course. The loop technique, however, results in a significantly longer line of leaflet coaptation and may therefore be more durable. Longer follow-up is required.
