Medical Device Daily Washington Editor

WASHINGTON — The second day of the inaugural med-tech conference hosted by the Advanced Medical Technology Association (AdvaMed; Washington) included a panel on what sort of advances might be expected from cardiovascular technologies in the 21st century.

Donald Baim, MD, chief medical officer at Boston Scientific (Natick, Massachusetts), discussed interventional cardiology, which he said has made “tremendous progress” despite “exceedingly poor outcomes” in the early years.

“This field reinvents itself every five years and is now the dominant form of revascularization,” Baim said, estimating that it accounts for 75% of all revascularization procedures.

Baim said that Andreas Gruentzig, MD, performed the world’s first angioplasty in 1977 but that the early returns daunted even Gruentzig. Baim quoted him as having said, “if I had an enemy, I would teach him angioplasty,” highlighting the initial difficulties in applying this therapy.

(Gruentzig died in 1985 of a condition unrelated to angioplasty’s difficulty.)

While medical technology advanced in the 1990s,“[e]ach new device ... had the potential to create new complications,” Baim said, those complications including thrombosis. He said that bare-metal stents are “inherently prothrombotic,” and that despite the negative coverage of drug-eluting stents (DES), they have reduced restenosis by half compared to BMS.

“I think the most important area of progress in 2008 and beyond is on how stents heal,” Baim said. One approach to enhancing luminal healing, he said, is to coat only the surface of the stent with the drug, and also perhaps by combining metal with a resorbable polymer.

He said that peripheral artery disease (PAD) will receive increasing focus. But because of the difficulties thus far found in DES use for coronary stenting, he predicted slower, more careful uptake.

“I don’t think we’ll be as exuberant,” he said, regarding DES use in other applications.

Baim said that FDA now wants more benchwork, better animal studies and larger clinical trials for new stenting applications, with enrollment up to 1,000 and two years of data, as well as post-approval studies of up to 5,000 patients enrolled.

All this will feed into a longer device development cycle, he said, predicting a cycle of “at least four years from concept to commercialization. At the same time, there’s a shrinking return” as more firms get into the business, and prices will also likely fall as a consequence.

Stephen Ramee, MD, the chief of cardiac catheterization at the Ochsner Clinic (New Orleans), also discussed PAD but said that cardiologists have a total focus on the heart, despite the fact that most are trained to deal with a wide range of vascular diseases.

He said a broader focus is needed by this group since “patients with one manifestation [of vascular disease usually] have coexistent disease” in other areas.

Ramee said that lower-extremity ischemia must be dealt with in order to head off consequent problems, and that these symptoms include cramping in the calves and fainting. “As in coronary applications, there are a lot of approved therapies “but basically it’s settled into stenting.”

The first trial for DES in PAD is about to begin, he said.

“We have about 99% success” in dealing with blocked peripheral arteries, Ramee said, but “our Achilles heel is also restenosis.”

A key problem is the movement in lower limbs, including knee flexion, affecting venous geometry, so stenting devices have to be designed to account for these issues.

Ramee said that renovascular disease is “a topic that’s under review” at the Centers for Medicare & Medicaid Services, adding that the incidence of this disease is 10%-20% among Medicare beneficiaries.

“If you have renal artery stenosis, it is a more powerful predictor of mortality” than a lot of cardiac indicators, including ejection fraction, he said. “Aggressive screening is indicated” for high-risk populations.

At present, there is no approved therapy for restenosis of renal vessels, although de novo lesions are generally dealt with via balloon angioplasties or angioplasties and stents. Ramee said he found it conspicuous that a CMS review panel for reimbursement for treatment of this disease had no interventionists on the panel.

Regarding cerebrovascular disease and neurointervention, Ramee said that “roughly three-fourths of a million people have a stroke every year” and “a third of the young people on long-term disability have stroke,” making this a huge population in need of effective therapies.

Stroke is second to coronary heart disease in mortality for all vascular diseases (54% to 18%), Ramee said, but he noted that carotid artery bifurcation apparently accounts for less than one-third of all ischemic stroke.

Other leading causes include other sites of stenosis, atrial fibrillation (AF) and the introduction of debris into the cranial vasculature via a patent foramen ovale PFO.

Ramee said that AF and debris into the cranial vasculature are responsible for as many as half of all cerebrovascular stroke.

Congresswoman Lois Capps (D-California) briefly addressed the gathering as a member of the health subcommittee for the House Energy and Commerce Committee and as a co-chair of the Congressional Heart and Stroke Coalition.

“I can’t help but think how far we’ve come just since my time as a nurse,” Capps said. “One of my most recent challenges was working on MDUFMA,” which she predicted will increase patient access and safety.

“I think the package we came up with is a good one,” she said, and will help FDA review products in a timely fashion. She said that House speaker Nancy Pelosi (D-California) intends to “pursue an innovation agenda,” which Capps said she supports.

“A very important part of the innovation agenda is to encourage women and girls to pursue careers” in medicine, which will help inform research in the future as to the differences in the ways that devices affect men and women. “I introduced the Heart for Women Act,” largely because heart disease kills more women than men, she said.

The bill seeks to ensure that women are represented in clinical trials and that FDA requires data on the effects of devices in women. The bill also would offer free cardiovascular screening for low-income women.

Capps said she had held a hearing earlier in the week on the Heart for Women Act, and that the House had passed the Stop Strokes Act (H.R. 477), which will improve early treatment of stroke and spread awareness of stroke in at-risk populations.

“Thank you for your leadership ... in increasing health opportunities for Americans,” Capps told conference attendees.