US Pivotal Trial Begins for St. Jude Medical's Amplatzer Cardiac Plug to Prevent Stroke in AF Patients

March 8, 2013—St. Jude Medical, Inc. (St. Paul, MN) announced the first patient implant in a new pivotal trial evaluating the company's Amplatzer cardiac plug (ACP) for the prevention of stroke. The ACP clinical trial is designed to determine if the device is safe and effective in preventing thrombus from migrating out of the left atrial appendage (LAA) in patients with nonvalvular atrial fibrillation (AF) who have a high risk for stroke.

The Amplatzer device for LAA occlusion was introduced outside the United States in 2008. The self-expanding occlusion device is constructed from nitinol mesh and delivered via catheter. It is designed to completely seal the LAA at its opening and minimize blood clots from forming in the LAA and migrating into the bloodstream.

The ACP device is currently not approved for use in the United States. The ACP trial is conducted under an investigational device exemption from the US Food and Drug Administration.

According to the company's press release, the ACP trial is a prospective, randomized, multicenter clinical study with an adaptive trial design that will enroll no fewer than 400 and no more than 3,000 patients at up to 90 sites in the United States and Canada. The trial compares the safety and efficacy of the ACP device to traditional medical treatment using long-term, blood-thinning medication.

St. Jude Medical stated each study site in the ACP trial will have physicians who specialize in electrophysiology and interventional cardiology, forming collaboration between the two specialties.

Investigator Christian Machado, MD, director of electrophysiology at the Providence Hospital Heart Institute in Southfield, Michigan, performed the first ACP implant in the pivotal phase of the trial. Pediatric interventional cardiologist Thomas Forbes, MD, who is also an investigator in the study, assisted in the procedure.

In St. Jude Medical's press release, Dr. Machado commented, “Patients with untreated AF are four to five times more likely to have a stroke, which greatly increases their risk of disability or death. Dr. Forbes and I consider the ACP trial an important study as we look for ways to reduce this risk. We are excited to contribute research that may help expand treatment options for patients.”

ACP trial investigator James Hermiller, MD, an interventional cardiologist from St. Vincent Hospital in Indianapolis, Indiana, observed, “The current standard of care for the prevention of stroke is warfarin or other oral blood-thinning medications that can be difficult for some people to tolerate and may carry a risk of serious complications, such as bleeding. As physicians, we are always looking for new ways to best treat our patients. We hope the ACP trial will prove that we can reduce the risk of stroke in patients with atrial fibrillation through this minimally invasive procedure.”

St. Jude Medical received CE Mark approval and launched the Amplatzer Amulet LAA occluder earlier this year. The Amulet occluder is built with a longer lobe and waist than previous versions of the Amplatzer device to allow for easier placement. The end screw is flush with the disc to create a smooth surface within the left atrium, and the larger disc diameter offers increased orifice coverage. The Amplatzer Amulet device is offered in eight sizes to accommodate varying anatomies. Additionally, the device is preloaded into the delivery catheter.