New treatment option for patients with aortic stenosis

Robert Stoler, MD, FACC, FSCAI, director of the Cardiac Catheterization Lab at Baylor Heart and Vascular Hospital (BHVH) and co-medical director, Division of Cardiology, is leading Baylor's participation in an exciting clinical trial to research a new treatment option for AS patients. BHVH is one of 45 national sites researching the use of the Medtronic CoreValve® transcatheter aortic valve replacement system as a treatment alternative to open-heart surgery. "Every research division in the country would like to have this study - we're proud that we can offer this opportunity to our patients," said Dr. Stoler.

Cardiovascular disease is the number one cause of death, killing more than 600,000 Americans each year. According to the American Heart Association, more than 5 million Americans are diagnosed with heart valve disease each year; approximately 5 percent of the population. Diseases of the aortic and mitral valves are the most common and up to 1.5 million people in the United States suffer from aortic stenosis (AS). The aortic valve consists of three tightly fitting, triangular-shaped flaps of tissue called leaflets and is positioned between the left ventricle of the heart and the aorta. The aorta is the largest artery in the body and carries the entire output of blood. Severe aortic stenosis occurs when the aortic valve does not open or close properly forcing the heart to work harder to pump blood through the body.

Approximately 500,000 of aortic stenosis patients are considered severe cases with half presenting symptoms. The most common symptom of the condition is chronic shortness of breath, however; patients may also experience chest pains or dizziness. Research shows that left untreated, severe aortic stenosis has a 50 percent mortality rate at two years - perhaps surprisingly, this is a survival rate below that of certain metastatic cancers.

Traditionally, the most effective treatment option has been replacing the aortic valve through open-heart surgery, an invasive procedure that carries many risks. Unfortunately, approximately one-third of severe aortic stenosis patients are not candidates for the open-heart surgery due to age or co-morbid conditions like lung, vascular and kidney disease, which leaves these patients with limited treatment options.

Earlier phases of the CoreValve trial evaluated whether the system was effective for patients at high risk, or ineligible, for open-heart surgery. Outcomes were promising and Baylor was recently awarded the next phase of the study, called SURTAVI, which looks at use of the valve in lower risk patients as compared with the outcomes from traditional open heart surgery. According to Dr. Stoler, "Because our data and the quality of the work taking place in the Baylor Cardiac Catheterization Lab is exemplary, we have a number of partners who are interested in bringing studies here and we're fortunate that we can offer our patients the opportunity to participate."

The procedure, which is minimally invasive, takes approximately two hours to complete. It is performed by making an incision in the femoral artery and delivering the new aortic valve via a catheter threaded up to the heart. The artificial valve is made of natural tissue with "leaflets" that control the flow of blood secured to a flexible, self-expanding frame for support. Since 2010, BHVH has successfully implanted nearly 50 CoreValves through this minimally invasive approach.

Patients who have received the system report an immediate improvement in their ability to breathe deeply and typical recovery time is between four and seven days. Dr. Stoler has high hopes that the CoreValve clinical trial will result in FDA approval for use in high-risk or inoperable patients within the next one or two years. He also anticipates that a successful trial will lead to new generations of valves from Medtronic and other device companies coming to trial as advances in the understanding of this treatment continue. Dr. Stoler believes that bringing clinical trials to Baylor benefits everyone, "patients have access to innovative technology, we're expanding scientific knowledge, and Baylor is recognized for leading the way in the field."

SOURCE Baylor Research Institute