The Coapsys device to treat functional mitral regurgitation: In vivo long-term canine study

Objective: We evaluated the capability of the Myocor Coapsys device (Myocor, Inc, Maple Grove, Minn) to reduce functional mitral regurgitation in a canine model of dilated cardiomyopathy. Methods: Functional mitral regurgitation with heart failure was induced in 7 dogs by rapid ventricular pacing. The Coapsys device, which consists of anterior and posterior epicardial pads connected by a subvalvular chord, was then implanted. Heart failure was maintained by continued pacing for 8 weeks. Hemodynamic and echocardiographic measurements were performed at pre- and postsizing and after 8 weeks. The Coapsys subvalvular chord was cut to verify that maintenance of valve competency was due to the device. Results: All implants were performed off-pump without atriotomy. Mitral regurgitation was reduced in all animals; mean mitral regurgitation grade was reduced from 2.9 +/- 0.7 to 0.7 +/- 0.8 (P = .00005) and was maintained at 0.8 +/- 0.8 after 8 weeks, without hemodynamic compromise or structural damage to the mitral valve. Mitral regurgitation returned to 3.6 +/- 0.8 (P = .102 versus presizing) after cutting the Coapsys subvalvular chord. Conclusion: The Coapsys device consistently and chronically reduced functional mitral regurgitation. This device is in clinical trials in the United States.