Medical Device Daily

Interventional cardiologists have long been challenged by coronary artery bifurcation lesions – branches or forks in the arteries – because treating those areas is associated with an increased risk of heart attack, restenosis and death. Three-year-old Stentys (Princeton, New Jersey and Paris) has just received the CE mark for what it says is the very first stent system that's disconnectable and-self-expanding, a platform specifically designed and approved to treat coronary artery bifurcations.

"Regular stents are made of steel that are like little metallic tubes that don't move," Stentys CEO Gonzague Issenmann told Medical Device Daily. "Our stent acts as a spring. This is the novel part. Other stents are not self extending. They stay where they are. The Stentys platform combines those two novel features (disconnectable and-self-expanding). That's unrivaled in this space and caters to the specific needs for difficult and challenging situations for the cardiologist."

The disconnectable feature allows cardiologists full access to a side branch of the artery and placement of a second stent.

"You can't fit a tube into a Y branch," Issenmann said. "The procedure used today to treat with regular stents is well known and accepted. It's a provisional stenting technique for bifurcations where you put a regular stent in main branch and try to find your way into the side branch. It doesn't scaffold well and you need to do a lot of ballooning. These techniques force the cardiologist to treat the side branch first and that's counterintuitive because they want to treat the most important vessel first.

"We propose something that has the advantage of keeping that same technique, but it's made easier by the disconnection feature that allows the cardiologist to open up the stent without distorting it. The advantage is that you use the same routine except that when you embark in the procedure, you can decide whether you want to access the side branch or not," he said.

The Stentys stent actually looks like it's got a side door.

The self-expanding feature insures optimal apposition in the critical initial hours and days after an acute myocardial infarction (AMI) procedure, according to the company. It's constantly applied to the vessel surface during thrombus and vessel spasm relief, therefore avoiding malapposition, a significant concern to cardiologists.

Although the CE mark was issued in connection with the bifurcation indication, Issenmann said it's also specifically designed for AMI procedures.

"It's built with special titanium alloy that gives the stent properties to act as a spring and can expand and push on vessel walls," he said.

"Patients who suffer from AMI are brought to the cath lab and basically they are there to reopen and recreate the flow with a stent," he said. "The problem is they are using stents designed to treat blockages of the coronaries that occur over time. They are not the ones that occur acutely. When you have this clotting of the artery that occurs immediately, you have a chain reaction in the artery . . . clots and spasms make it smaller. With a regular stent, you have a problem with sizing. The stent is often not properly opposed to the vessel wall. This is one of the biggest predictors of reclotting later on – because it wasn't properly placed where the initial clot was."

Issenmann said the Stentys stent "allows for perfect opposition of the stent to prevent malapposition and recurrence of clots. Only a self-expanding stent can do that."

He added that the stent ultimately reduces the potential for restenosis.

To obtain the CE mark, Stentys used data from its OPEN I (First-In-Man study of the Stentys Coronary Bifurcation Stent fOr the Percutaneous treatmEnt of de-novo lesions in Native bifurcated coronary arteries) study.

Forty patients were enrolled in OPEN I between September 2007 and September 2008 at nine European clinical sites. The prospective, non-randomized, single-arm, multicenter safety and feasibility study found that it was safe, doesn't fracture over time, has results similar to balloon-expandable bare metal stents, provides excellent cross-over treatment of bifurcations, the stent remained perfectly opposed to the treated vessels and there were no deaths or reoccurrence of heart attack during the six-month follow-up period.

The company intends to start commercializing the stent in Europe during the first half of 2010 and has started discussions with the FDA, although no U.S.-based studies are yet planned.

Stentys is currently conducting another trial with the same stent seeking CE mark for the AMI indication. Another larger study will begin later this year that will compare the Stentys stent with a balloon expandable stent.

Stentys last month managed to secure the second tranche of a Series B financing, closing an additional $4.2 million investment from new investor bringing the total B round financing to more than $22 million (MDD, June 30, 2009).

"Basically the proceeds of this are good toward the continuation of our clinical program," Issenmann said. "We actually raised more than expected, so that gives us even more runway. In all fairness, we were fortunate. When I hear war stories about what's going on in the U.S. to raise money, I know we have an advantage of being on both sides of the ocean."

Stentys was co-founded by Issenmann and Jacques S guin, MD, founder of CoreValve, a company which was acquired earlier this year by Medtronic for $700 million (MDD, Feb. 24, 2009).