The Canadian Mitral Research Alliance (CAMRA) Trial CardioLink-2 (CAMRA)

A Randomized Trial of Mitral Valve Repair With Leaflet Resection Versus Leaflet Preservation on Functional Mitral Stenosis: The Canadian Mitral Research Alliance (CAMRA-1) Trial

Multicentre, double-armed, randomized controlled trial designed to compare mitral valve leaflet resection versus leaflet preservation with regards to the development of functional mitral stenosis following surgical repair of mitral valve prolapse. Patients will be randomized (1:1) to receive: (1) mitral valve repair with a leaflet resection or (2) mitral valve repair with leaflet preservation (using polytetrafluoroethylene neochordae), followed by echocardiographic and clinical assessment at 12-months following surgery.

Mitral valve repair has emerged as the preferred surgical treatment for mitral valve prolapse (MVP), a condition wherein the mitral valve does not close properly. One common strategy for mitral valve repair is leaflet resection, which involves removing part of one or both of the mitral leaflets that flop or bulge back (prolapse). Another strategy is leaflet preservation, which involves placing man-made fibers (sutures) to more securely connect the mitral leaflets to the papillary muscles (muscles located in the ventricle). While both strategies are routinely used and lead to successful mitral valve repair, there is no clear evidence as to whether one strategy is better than the other in terms of long term outcome. The purpose of this study is to determine if one repair strategy (leaflet resection versus leaflet preservation) leads to better longer term patient outcomes. A total of 88 patients from 6 Canadian centres will be randomly assigned to one of the two strategies. The primary outcome will be functional mitral stenosis (MS) as assessed by 12-month mean mitral valve pressure gradient at peak exercise.

Placing man-made fibers (sutures) to more securely connect the mitral leaflets to the papillary muscles (muscles located in the ventricle).

Placing man-made fibers (sutures) to more securely connect the mitral leaflets to the papillary muscles (muscles located in the ventricle).

Composite MACE (major adverse cardiovascular event) end-point of recurrent MR ≥2+, death, or hospital re-admission for congestive heart failure within 12-months of surgery

Inclusion Criteria: Patients with mitral regurgitation and mitral valve prolapse who are scheduled for elective mitral valve repair by an experienced mitral valve repair surgeon (>15 degenerative mitral valve repairs per year, with a repair rate>90%, and able to perform mitral repair with either a leaflet resection or leaflet preservation strategy). Planned mitral valve repair amenable to either a leaflet resection or leaflet preservation surgical repair strategy Exclusion Criteria: Patients with anterior leaflet or commissural prolapse Patients with endocarditis or rheumatic mitral valve disease Patients with mitral annular calcification extending beyond the circumference of one leaflet scallop Patients with significant LV dysfunction defined as a LVEF <40% Patients undergoing concomitant aortic valve surgery Patients unable to undergo bicycle ergometry

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