Study evaluates safety and effectiveness of Diamondback device for heart attacks

Nov 23 2011

Drilling through concrete to create an opening may sound more like construction than medicine, but the approach is similar to what researchers at Orlando Regional Medical Center (ORMC) are doing in a clinical trial to evaluate a device that breaks through hardened coronary arteries, in an effort to prevent heart attacks and relieve chest pain.

The study evaluates the effectiveness and safety of the Diamondback 360◦ orbital technology which uses a tiny, orbiting diamond-coated crown to gently sand away calcified plaque and restore blood flow.

"This device is the next generation in the removal of this type of severe calcification in coronary arteries," said Barry Weinstock, MD, an interventional cardiologist at ORMC's Cath Lab and principal investigator for the clinical trial at ORMC. "During the last 20 years, technology has continued to improve with balloon angioplasty, and stents to keep arteries open, but the technology to treat calcified plaque in the arteries has not kept up as much."

The Diamondback's diamond-coated crown orbits in the coronary arteries with speeds varying from 80,000 to 120,000 times per minute, breaking up the plaque along the way into microscopic particles which are digested and excreted.

"The result is similar to what happens when a tablespoon of sugar is dropped into boiling water, it disappears," said Dr. Weinstock.

The procedure begins with a catheter inserted through an incision in the groin. Dye is injected to visualize the coronary arteries. A fine wire, the size of a strand of hair, is inserted into the artery through the catheter. The Diamondback catheter slides along the wire like a train on a track. Once the device removes the calcified plaque, a stent is typically placed to further open the artery and to minimize the chance of the artery re-clogging in the future.

Using orbital technology may mean better outcomes for patients.

"This new approach may be an effective, minimally invasive alternative for many patients who would otherwise require open-heart surgery," said Dr. Weinstock. "Recovery from open heart or bypass surgery can take as long as a week or longer. Using the orbital device, most patients are back home the day after the procedure and at work the next day."

Severely hardened coronary arteries, a type of atherosclerosis, can restrict blood flow causing chest pain and other symptoms such as shortness of breath.

"More concerning, the plaque can rupture causing a blood clot which can trigger a heart attack," said Dr. Weinstock.

Because the condition develops over time, mild atherosclerosis may not have symptoms. Once an artery is more severely clogged and blood flow is more severely restricted, common symptoms are similar to those of a heart attack, including chest pain.

"Risk factors for the development of coronary artery disease include high cholesterol, high blood pressure, diabetes, a family history of early heart disease, and smoking," said Dr. Weinstock. "Patients with kidney disease and/or diabetes as well as more elderly patients are more likely to have severely calcified plaque that may need to be treated with a device such as the Diamondback 360."

ORMC currently uses orbital technology to treat peripheral arterial disease (PAD), a build-up of plaque in the leg arteries that can lead to severe and debilitating leg pain or even amputation. The device already approved by the U.S. Food and Drug Administration (FDA) to treat PAD, is an alternative for surgery or amputation.