With the positive initial results of the CREST trial released in February, more facilities will begin exploring the idea of implementing a carotid artery stenting (CAS) program and weigh the challenges—including turf battles—and  benefits, such as multidisciplinary cooperation.

Complementary, not competitive

Reimbursement for CAS in the U.S. is approximately $2,000 per procedure and it is restricted to symptomatic patients at high risk for stroke and surgery with at least 70 percent stenosis. The procedure also must include embolic protection. In the CREST trial, however, CAS in patients with a “standard risk” showed similar rates of stroke, MI and death as patients in the carotid endarterectomy (CEA) arm. While these data need to be studied further, stenting proponents say the trial’s results could help expand the indications, making the possibility of adding a carotid stenting program to a facility’s service line all the more attractive. But there are turf issues to consider.

CEA is the most common procedure for U.S. vascular surgeons, who perform almost 200,000 of them per year, “so they may try to block interventional cardiologists from performing CAS,” says Donna Marchant, MD, an interventional cardiologist at North Shore University Hospital in Manhasset, N.Y. Marchant and colleagues have been performing CAS since 1999, but it took some time for them to iron out the turf issues. They had to prove to hospital administrators that CAS was a safe alternative to CEA, and that they were well trained to perform it. “The more training you have, the easier it will be for administrators to support you,” she says.

Cardiologists at Ochsner Medical Center in New Orleans faced similar problems, says Stephen Ramee, MD, head of interventional cardiology and director of the cardiac cath lab. “When you have progress, something has to die for its replacement to fill in,” says Ramee, adding that vascular surgeons are lobbying the FDA to recognize that there are not enough data to support CAS. “There are some politics involved. It’s not always about the science and, unfortunately, this has stifled the growth of CAS procedures.”

W. Charles Sternbergh, III, MD, head of the department of vascular and endovascular surgery at Ochsner, says that medical therapy, CEA and CAS are complementary and proper patient selection is key to achieving success in any treatment plan. CREST clearly showed that certain subgroups are better served with stenting, while others are more suited for surgery. “Carotid stenting now is widespread,” says Sternbergh. “It worries me that groups may be thinking about starting a carotid stenting program just because it’s reimbursed.”

Gary S. Roubin, MD, PhD, chairman of the department of interventional cardiology at Lenox Hill Hospital in New York City and a CREST investigator, predicts that the positive results of CREST will influence CMS to change its reimbursement scheme within the next six to 12 months. In the meantime, Roubin and colleagues are not marketing their CAS program. Patients come from referrals. If CMS widens the indications to include standard risk and/or asymptomatic patients, Lenox Hill will market its CAS service, and will include outcomes data in any marketing push, says Roubin.

Regulatory & societal caveats

CMS requires facilities that are approved to perform CAS to be recertified every two years. To do so, the facility must turn over specific data elements to CMS including physician training standards, device inventory and outcomes data. Facilities also must have a high-quality digital imaging system, advanced physiologic monitoring, emergency management equipment and an oversight committee to evaluate interventionalists and the overall quality of the CAS program. CMS suggests that an internal analysis of the data occur no less than every six months.

It’s incumbent upon each institution to determine written competency standards for physicians. The consensus statement issued by the Society of Cardiovascular Angiography and Interventions (SCAI), in conjunction with the Society of Vascular Medicine and Biology and the Society for Vascular Surgery, suggests a minimum of 30 diagnostic cerebrovascular angiograms (15 as the primary interventionalist) and 25 CAS procedures to demonstrate competency. Some other societies suggest higher minimum numbers. Ultimately, it’s up to the facility to decide.

The SCAI consensus statement suggests two physician training pathways: One during fellowship and a practice pathway for clinicians in practice. Practicing physicians should be fully credentialed to perform peripheral interventions at their facility and should be actively performing endovascular procedures prior to undertaking focused carotid training. “If a physician is already an interventionalist in surgery, radiology or cardiology and has the requisite skill set, the first step would be to acquire peripheral endovascular credentialing and privileging within his or her institution,” says Kenneth Rosenfield, MD, director of cardiac and vascular invasive service at Massachusetts General Hospital in Boston and lead author of the SCAI consensus statement.

“You have to spend a significant amount of time with somebody who performs CAS,” says Sternbergh. “Learning which patient to treat and which not to treat is just as important as learning the technique.” In agreement, Ramee points out that many high-volume centers have “worked out the kinks” and will proctor clinicians on the procedure. Physicians also can enroll in didactic courses—online and otherwise.

Rosenfield promotes the use of simulation to gain experience, saying it “allows new operators to learn about anatomy, tools and some of the complications that might be encountered prior to doing live cases. A major benefit of simulation is that a procedure can be halted without any downside to a patient, and a mentor can discuss various options within the procedure.”

The CAPTURE trial results revealed that patients fared equally well whether treated by highly experienced physicians or those who were new to carotid stenting but had undergone intensive training and on-site mentoring during their first few procedures (Catheter Cardiovasc Interv 2007;69:341-348). Roffi et al reported that a CAS-fellowship-trained interventionalist stenting 100 patients in a new CAS program had a 30-day major adverse event rate of 1.9 percent (Catheter Cardiovasc Interv 2008;71(4):474). And the transradial approach is safe and technically feasible for CAS, according to Folmar et al (Catheter Cardiovasc Interv 2007;69(3):355-61). “The [transradial] technique may be particularly useful in patients with right internal carotid artery lesions and severe peripheral vascular disease or unfavorable arch anatomy, and among patients with a bovine aortic arch,” they concluded.

The CREST trial had rigorous qualifying standards for investigators, which “underscores the importance of having appropriate skill sets and extensive training before undertaking carotid stenting as a primary or independent operator,” says Rosenfield. He also notes that it is unlikely CREST will change anything regarding credentialing, but CMS may weigh in at some point. “There are two efforts at establishing hospital accreditation requirements, and CMS has signaled interest in utilizing them if the coverage decision is to change."

Ultimately, a successful CAS program would mean that multidisciplinary teams from cardiology, radiology, vascular surgery and neurology are working together to determine the best approach to treat carotid disease. It also means that reasonable but strong competency guidelines are enforced and that data are collected to analyze outcomes. Finally, it means that providers can offer patients another option of care.