Secondary mitral regurgitation (MR) can be a serious complication of heart failure — in a recent study, two-thirds of the people who were taking the maximum recommended doses of drugs for severe forms of the disease were hospitalized or dead within two years.
But researchers at a widely watched medical device conference in San Diego said this past weekend that when a similarly sized group of patients had a MitraClip heart device made by Abbott Laboratories implanted, the rate of hospitalization and death dropped to 46 percent. Abbott's "Coapt" trial, which included patients at several Minnesota hospitals, was described as giving doctors a long-sought way to treat secondary MR.
The stock market greeted the news by sending Abbott shares up more than 3 percent, closing at $71.44 on Monday. Abbott officials said Monday that the Coapt study results show promise.
"Patients had fewer heart failure hospitalizations, a reduction in risk of death, and quality of life was improved. These are all things that are really important to patients," Barathi Sethuraman, divisional vice president of clinical affairs in Abbott's structural heart business, said Monday from the annual Transcatheter Cardiovascular Therapies (TCT) symposium of the Cardiovascular Research Foundation.
"Transcatheter" refers to medical devices that can be put in the body without surgery. Typically, these minimally invasive devices are folded inside catheters and then inserted into the diseased heart or blood vessel using live X-rays to navigate. The medical team unfurls the heart valve, stent or other device, then withdraws the delivery catheter from the puncture site in the leg or wrist.
Abbott's MitraClip has been approved in the United States since 2013 as a minimally invasive treatment for primary MR, which happens when the mitral valve itself becomes diseased and allows blood to flow backward in the heart.
Doctors have been using the MitraClip experimentally to treat secondary MR, which occurs when blood flows backward through the mitral valve. This happens when the heart's overall shape has changed as part of advanced heart failure, which distorts how the valve's leaflets open and close.
For cases using one device, the MitraClip secures the valve's leaflets near the center, in effect creating two smaller valves — one on each side of the clip — that continue to open and close with a better seal, so that blood only moves in the intended direction through the heart. (The average number of clips used in the study was 1.7 per patient.)