The device -- the MitraClip -- helps the heart valve close more effectively, rather than allowing leakage of blood backward into the left atrium -- a condition know as mitral regurgitation. Catheter-mounted, it can be installed through the femoral vein in the groin and does not require open heart surgery.

Twenty-three patients were treated with the MitraClip at 15 medical centers and compared to patients treated with open heart surgery.

After the procedure, mitral regurgitation was mild to modest in 19 of 22 patients -- 83 percent -- treated with the MitraClip.

"One trouble with mitral regurgitation is that the heart has to work harder, and over time, it dilates and enlarges," study leader Dr. James Hermiller of the St. Vincent Heart Center of Indiana in Indianapolis said in a statement. "Demonstrating that the left ventricular enlargement is actually reversing itself is important objective evidence that the heart is responding favorably. It confirms that there's something real here."

Hermiller reported the findings at a scientific meeting in Chicago of the Society for Cardiovascular Angiography and Interventions in partnership with the American College of Cardiology.