Reversible implant appears safe, but more study is needed, researchers say
TUESDAY, June 23 (HealthDay News) -- A new method of repairing leaking mitral heart valves appears safe, a small study shows.
In the new study, researchers tested a reversible implant called the Percutaneous Transvenous Mitral Annuloplasty (PTMA) system, which is installed via a catheter.
In the heart, the mitral valve controls the flow of blood from the left atrium into the left ventricle (from the upper left chamber into the lower left chamber). A leaking mitral valve causes blood to flow back into the left atrium. This condition can worsen existing heart failure or cause congestive heart failure, according to a news release from the American Heart Association.
Currently, mitral valve repair requires opening the chest and putting the patient on a heart-lung machine. This method increases the risk of heart attack and stroke during surgery, as well as post-surgery risks such as lung problems, irregular heartbeat and infection, the news release noted.
The PTMA system changes the shape of the mitral annulus (a fibrous ring encircling the mitral valve) and prevents blood leakage by allowing the valve's two leaflets to close more tightly.
"Heart failure prevalence is worsening, and we know that the outcome of congestive heart failure is worse when mitral regurgitation is present," study author Dr. Stefan Sack, chief of cardiology, pneumology and intensive care at Schwabing Hospital in Munich, Germany, said in the news release.
The study included 27 patients, nine of whom received PTMA implants. However, four of those implanted devices had to be removed because of complications. While no deaths, heart attacks, stroke or emergency surgeries occurred among the 27 patients, four suffered at least one major adverse event, such as pneumonia, temporary kidney dysfunction, or accumulation of fluid around the heart. The researchers noted that the PTMA system will not be recommended for all patients due to various anatomic and disease-specific causes, and they stressed that more study is needed before the medical impact of the device can be determined.
The study, which appears in the June 23 online issue of Circulation: Cardiovascular Interventions, was funded by Viacor, which makes the PTMA system.
The Society of Thoracic Surgeons has more about mitral valve repair.
-- Robert Preidt
SOURCE: American Heart Association, news release, June 23, 2009
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