New self-expanding stent used for first time

Three patients with established cardiac ischemia recently became the first recipients of the vProtect Luminal Shield, a self-expanding intracoronary prosthesis designed to limit arterial injury that typically occurs when stents are deployed. The Shield also provides robust biocompatible support for the vessel to ensure that the target coronary artery will remain patent after placement, according to its developer, Prescient Medical (Doylestown, Pennsylvania).

The patients were treated May 8 and 9 by Juan Granada, MD, of the Cardiovascular Research Foundation (New York) and Juan Delgado, MD, at the Corbic Institute-MUA (Envigado, Colombia). The target lesions ranged from 60% to 80% stenosis before the vProtect Luminal Shields were deployed. These were the first three human cases studied using the device, Illana Odess, general manager of interventional cardiology, for Prescient, told Medical Device Daily, but the company still has to do a 30-day follow-up on each of the patients. The vProtect Luminal Shield is an implantable device belonging to the stent family, she said, however, that its self-expanding nitinol design differentiates it from balloon-expandable stents. Because it is self-expanding, the Shield produces less arterial injury on deployment, compared with balloon-expanding stents. Another unique feature of the device, Odess said, is that the primary structural elements of the Shield are longitudinal rather than circumferential, as most stents for non-coronary applications are built.

“We designed it so it is longitudinal and the main reason for that was to capture or trap healthy cells,” she said. “We want to promote healing and we believe that as soon as you capture healthy cells you promote the healing aspect of it.” The device also features thin 56-micron struts, the thinnest on the market, Odess said. According to the company, thinner struts cause less injury and promote faster endothelial regrowth and vessel healing. She said the next step for the company is a CE-mark study with plans to seek a CE mark later this year. Prescient also plans to start a pivotal trial in the U.S. later this year, she said, and hopefully get FDA approval for the device in 2011 or 2012. The company hopes to commercialize the device outside the U.S. in 2Q09.

While commercialization of the device outside the U.S. still is at least a year down the road – and even farther down the road in the U.S. – Odess said the company saw “excellent results” with these first three human cases. In the first patient, a 75% occlusion in the mid-circumflex coronary artery underwent pre-dilatation at low pressure with a 2.5 mm x 9 mm balloon and then received a 3.5 mm x 15 mm Luminal Shield. After gentle post-dilatation, angiography revealed that blood flow had been restored to the distal portion of the treated vessel. In the second patient, an 80% occlusion in the middle of the left anterior descending (LAD) branch required pre-dilatation with a 2.5 mm x 9 mm balloon. Additional lumen gain was achieved by Shield placement and post-dilatation, again achieving restoration of blood flow distal to the treated segment.

The third patient was a challenging case with a 65% occlusion in the mid-LAD, located in a bend near a side branch ostium. The vProtect Luminal Shield was chosen for this patient based on its mechanical properties, including high vascular conformability. Because of its flexibility, the vProtect Luminal Shield was able to access the tortuous anatomy and cross the lesion successfully. Restoration of flow was achieved without angiographic evidence of straightening of the target vessel, a common occurrence with rigid balloon-expandable stents. In addition, the side branch was preserved without evidence of plaque shifting or worsening stenosis.

“The vProtect Luminal Shield and delivery system performed extremely well,” Granada said. “The three patients we treated presented with lesions representative of what we see in daily clinical practice and we were able to cross these lesions and deliver the device safely in each case. Although the vProtect Luminal Shield has ultra-thin struts to promote healing, it maintains an intrinsic radial force that matches the vessel compliance. I am very pleased with these early results.” Prescient is a privately held device company founded in 2004 to reduce the number of deaths from heart attacks, Odess said. She noted that “every 60 seconds, one American dies [from a heart attack].”

Most of the executives at Prescient, including Odess, came from Johnson & Johnson‘s (New Brunswick, New Jersey) Cordis (Miami Lakes, Florida) business and went on to find other careers in interventional cardiology.

“And 10 years later we still felt we had an unmet need,” Odess said. “We wanted to have a detection and then a treatment, which we call prevention.” The “detection” component of the “prevention platform” comes from another device the company is developing called the vPredict Optical Catheter System, designed to “rapidly analyze materials within arterial walls during a procedure we call Optiography,” she said. The system is intended to detect and characterize atherosclerotic plaques that may be vulnerable to rupture, Prescient said.

Source: Medical Device Daily

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