Mar 17, 2010 5:01 PM
March 17, 2010 (Atlanta) -- A clothespin-type device that clips together the partially open doors of leaky heart valves may spare some patients the need for open heart surgery, doctors say.
In a new study, the clip was safer and worked nearly as well as surgery for people with the leaky valve condition known as mitral valve regurgitation.
But the patients were only followed for one year -- not enough time to truly gauge the effectiveness of the new technique, some experts say.
About 250,000 Americans are diagnosed with mitral valve regurgitation each year. The mitral valve is like a saloon door that opens to let blood flow into the heart's main pumping chamber. When it fails to close properly, blood flows backward, sapping the efficiency of the heart. Over time, as the heart continues to weaken, patients can develop life-threatening heart failure.
For people with severe symptoms, such as breathlessness when walking across the room, doctors typically offer surgery, which involves splitting open the chest to repair or replace the valve. About 100,000 Americans have mitral valve surgery each year, says study head Ted Feldman, MD, of NorthShore University Health System in Evanston, Ill.
If the patient is too old or has too many other health problems to tolerate surgery, heart failure medications are given, he says.
These are the patients most likely to benefit from the new device, called MitraClip, experts say. It's already on the market in Europe and is awaiting FDA approval.
The tiny clip is mounted onto a catheter and then threaded into the heart through an incision in an artery in the groin. The technique is similar to that used in angioplasty procedures to open clogged heart arteries.
The new study involved 279 patients: 184 were assigned to get the MitraClip and 95 to surgery. The clip procedure was attempted in 178 patients and successful in 137.
The findings were reported at the annual meeting of the American College of Cardiology (ACC).
Ten percent of people treated with the clip experienced major complications within 30 days, compared to 57% who underwent surgery. There were no deaths with the clip; two surgery patients died.
As for effectiveness, the study was designed to show that the device was not substantially inferior to surgery at one year and by that test, it passed. After one year, 72% of MitraClip patients and 88% of surgery patients did not have serious leakage, which showed the clip was not statistically inferior to surgery, Feldman says.
Unlike surgery patients, who can be in the hospital for nearly a week after open heart procedures, people treated with the clip are often up and walking around within a day or two, Feldman says.
"We have opened the door for a new option for patients," Feldman says.
Some surgeons expressed concerns that the new device is not as good as surgery.
"The first issue is, how will it hold up after 12 months?" says J. Scott Millikan, MD, a surgeon at the Billings Clinic in Montana.
"A year may not be enough time to gauge its effectiveness," he tells WebMD, adding that surgical repair often holds up for more than a decade.
"This represents a step forward, but we need more study, larger studies," Millikan says.
Feldman notes that if the clip fails, surgery is still an option, so it makes sense to use the less drastic treatment first.
ACC President Alfred Bove, MD, of Temple University in Philadelphia, says he is concerned about the 41 failed attempts at clip repair.
Feldman says it's a new technique and doctors are getting better at performing it.
Donald Glower, MD, a heart surgeon at Duke University who was involved with the study, says the clip probably will be especially helpful for patients too old, frail, or sick to have surgery.
The study was funded by Evalve Inc., which developed the device. Evalve was sold last year to Abbott; Feldman consults for the firm.
The device costs about $22,000 in Europe; the price in the U.S. has not been set.