Cardiac Procedure Significantly Reduces Risk of Alzheimer's Disease and Stroke

New research presented at National Heart Rhythm Society Sessions shows ablation treatment can eliminate serious risks associated with atrial fibrillation

MURRAY, UT (5/13/2010) – New findings by researchers from the Heart Institute at Intermountain Medical Center reveal treatment of the most common heart rhythm disorder that affects more than two million Americans significantly reduces the risk of stroke, mortality, Alzheimer’s disease and other forms of dementia.

According to two new studies by the Intermountain Medical Center research team presented Thursday (May 13) at the national Heart Rhythm Society’s 31st Annual Scientific Sessions, patients with atrial fibrillation treated with catheter ablation are less likely to develop Alzheimer’s disease or other forms of dementia, and have a significantly reduced risk of stroke and death compared to A-fib patients with who are not treated with ablation.

During atrial fibrillation, the heart's two small upper chambers quiver instead of beating effectively. Blood isn't pumped completely out of them, so it may pool and clot. If a piece of a blood clot in the atria leaves the heart and becomes lodged in an artery in the brain, a stroke results. A-fib is the most common heart disorder found in about 2.2 million Americans. Three to five percent of people over 65 have atrial fibrillation.

Catheter ablation is a type of treatment for cardiac arrhythmias. During ablation, a doctor inserts a catheter (thin, flexible tube) into the heart. A special machine delivers energy through the catheter to tiny areas of the heart muscle that cause the abnormal heart rhythm. This energy “disconnects” the pathway of the abnormal rhythm.

Over a three-year period, researchers from the Heart Institute at Intermountain Medical Center enrolled 37,908 patients in a large, on-going prospective atrial fibrillation study at Intermountain Medical Center. Patients were split into three groups, all matched in gender and age: A-fib ablation patients, A-fib patients treated with medications, and patients without A-fib.

The studies, led by cardiologists John D. Day, MD, and T. Jared Bunch, MD, from the Heart Institute at Intermountain Medical Center, evaluated the long-term effects of ablation treatment on patients with A-fib and the likelihood of developing dementia, Alzheimer’s disease, stroke, and death. Both studies showed that 64 percent of A-fib patients treated with catheter ablation were cured of A-fib and off anti-arrhythmic medications at the end of the three year period.

Study findings showed that A-fib ablation patients have a significantly lower risk of developing Alzheimer’s disease or other forms of dementia in a large cohort of patients. Specific study findings include:

• A-fib ablation patients: 0.2 percent developed Alzheimer’s disease, and 0.4 percent developed other forms of dementia
• A-fib patients with no ablation intervention (treated with medications): 0.9 percent developed Alzheimer’s disease and 1.9 percent developed other forms of dementia

Results also revealed that A-fib patients who underwent catheter ablation had a lower risk of stroke and death when compared with A-fib patients who did not receive ablation treatment. Specific study findings include:

• A-fib ablation patients: 2.2 percent suffered a stroke, and the mortality rate was 6%
• A-fib patients with no ablation intervention (treated with medications): 4.7 percent suffered a stroke, and the mortality rate was 23.5 percent

In May of 2009, the Intermountain Medical Center research team presented results from a breakthrough study in which they linked the presence of a-fib to the development of Alzheimer’s disease. These two new studies presented on Thursday build on those findings and show that intervention can significantly reduce one’s risk for further progression of dementia and Alzheimer’s disease, says Dr. Day

“With millions of people affected by atrial fibrillation, it is our hope that findings from studies like ours will help clinicians determine the best possible care and treatment options for patients,” says Dr. Day. “Our studies shed light on the positive outcomes of catheter ablation treatment not only to reduce atrial fibrillation, but also to help A-fib patients lower their risk of developing Alzheimer’s disease, suffering from a stroke or worse, loss of life.”