Physician scientists present new findings on aspirin therapy, atrial fibrillation drug therapy and LVAD

Mar 19 2010

Physician scientists from the Cedars-Sinai Heart Institute presented new findings on the effectiveness of routine aspirin therapy for preventing heart disease, a drug therapy for atrial fibrillation and the role left ventricular assist devices (LVADs) may play in weight reduction for obese patients with chronic end-stage heart failure who are considered for heart transplantation. These presentations were made at the American College of Cardiology's Scientific Session in Atlanta. Brief highlights from these studies are included below.

In addition to these presentations, Cedars-Sinai Heart Institute researchers will present findings on gender differences, minimally-invasive surgery, treatments for coronary artery disease and more. For a full listing of Cedars-Sinai presenters, please email [email protected].

Does Contemporary Trial Evidence Support the Routine Use of Aspirin in Primary Prevention of Heart Disease?

Although current guidelines generally recommend routine use of aspirin for primary prevention of heart disease in men and stroke in women, a meta-analysis of nine trials (104,331 patients) that had evaluated the efficacy of aspirin use in primary prevention of cardiovascular events suggests that aspirin therapy does not result in significant reduction in serious vascular events in either gender. The study indicated that aspirin therapy resulted in a minimal reduction in cardiovascular events, but it also resulted in a modest increase in bleeding risk.

"The results of this study challenge current guidelines regarding aspirin use for cardiovascular disease prevention," said Sanjay Kaul, M.D., director of the Vascular Physiology and Thrombosis Research Laboratory at the Burns and Allen Research Institute at Cedars-Sinai.

Dronedarone: New Atrial Fibrillation Drug Not Recommended as a "First Choice"

Recently approved as a therapy for patients with atrial fibrillation/flutter, Dronedarone was specifically designed to overcome the side effects of its parent compound, amiodarone, while effectively reducing arrhythmias. However, say the authors, there are uncertainties with respect to the drug's efficacy and safety. In an analysis of several clinical trials that have evaluated the impact of dronedarone on various cardiovascular end points and yielded mixed results, Cedars-Sinai cardiologists concluded that the available data support the use of dronedarone in select patient populations as a second- or third-line agent, but not as a therapy of first-choice in most patients with atrial fibrillation.

"In general, based on available evidence, it is difficult to support an approach to rhythm control in most patients with atrial fibrillation without first trying a rate-control strategy. More studies with longer follow-up are needed," says senior author Sanjay Kaul, M.D., director of the Vascular Physiology and Thrombosis Research Laboratory at the Burns and Allen Research Institute at Cedars-Sinai.

Implantation of a Ventricular Assist Device may aid in Weight Loss for Obese Patients Awaiting a Heart Transplant

For patients who are awaiting a heart transplant, Left Ventricular Assist Devices (LVAD) can literally mean the difference between life and death - helping the patient's own weakened heart to continue pumping until a suitable donor organ becomes available. In this study, Heart Institute physicians and surgeons note that in addition to assisting the patient's own heart, LVADs can aid obese heart transplant patients in weight reduction. Weight loss in such patients is important because just as obesity is a risk factor for heart failure, it also is associated with poor outcomes after a heart transplant. It is therefore considered a relative contra-indication for transplant.

In this analysis of 19 patients who were awaiting a transplant, obese advanced heart failure patients lost more weight and reduced their body mass index (BMI) significantly after being implanted with an LVAD. Obese patients who received the device lost about 12 percent of their body weight, nearly double the amount of weight lost by patients who were not obese.

According to researchers, the weight loss in patients implanted with the LVAD likely resulted from a combination of factors: the device possibly caused more calories to be consumed while simultaneously also resulting in decreased caloric intake.

While the obese patients were previously very sedentary, the LVAD provided more cardiac capacity, thereby enabling these patients to become more active, improve their overall conditioning, and expend more calories. In addition, the total weight, shape and physical location of the LVAD in the abdomen likely played a role in reducing caloric intake.

"Achieving adequate weight loss appears difficult among obese heart failure patients who are unable to exercise due to de-conditioning and reduced cardiac capacity," said Ernst Schwarz, M.D., Ph.D., director of Multidisciplinary Heart Failure Research at the Cedars-Sinai Heart Institute. "LVADs could prove to be helpful in improving obese patients' outcomes."

Source: Cedars-Sinai Medical Center