The recent move to expand Medicare coverage of carotid stenting formed the basis of a recent debate over the wisdom of the decision taken by the Centers for Medicare & Medicaid Services (CMS). Two heavyweights in the stroke arena went head-to-head, sparring over whether the decision should have been taken at all.
Two luminaries in the field of stroke prevention weighed in on opposite sides of a still-raging debate over whether the recent decision by CMS to expand Medicare coverage for carotid artery stenting (CAS) was the right move to make amid conflicting opinion on what the weight of the scientific evidence says on carotid revascularization interventions.
Thomas Brott, MD, a professor of neurology at the Mayo Clinic in Jacksonville, Florida, and a principal investigator of the ongoing and keenly followed CREST-2 (Carotid Revascularization Endarterectomy vs. Stenting Trial-2) study, and Anne Abbott, MD, a neurologist at Central Clinical School, Monash University, in Melbourne, Australia, took up opposing positions during the 2023 VEITHsymposium back-and-forth in New York City (Nov. 14–18).
Brott took up that position that, “Since TCAR [transcarotid artery revascularization] already has it, reimbursement for transfemoral and transbrachial carotid stenting should be expanded to include asymptomatic patients.” Abbott pushed back strongly, arguing, “There should be no reimbursement for CAS or TCAR in asymptomatic or symptomatic [patients].”
Brott took issue with recent published writings from Abbott in which she stated that stenting near the transaortic root causes more procedural stroke, death and heart attacks than does carotid endarterectomy (CEA); that there is no randomized trial evidence of patient benefit from any carotid procedure compared with current standards of non-invasive care alone; that crucially needed trials such as CREST-2 to assess procedural efficacy will be exceedingly difficult if not impossible to complete; and that the CMS funding changes “will open the floodgates.”
Regarding Abbott’s point on unfavorable outcomes in stenting vs. CEA near the transaortic root, “where she emphasizes randomized trial evidence,” Brott contended that “that’s not true for CREST; that’s not true for ACST-2 [Asymptomatic Carotid Surgery Trial-2]; it’s not true for ACT-1 [Asymptomatic Carotid Stenosis]; and it’s not true for the combined analysis of CREST and ACT-1—all randomized trials.”
Brott turned to Abbott’s assertion of no randomized trial evidence of patient benefit from any carotid procedure compared to current standards of non-invasive care. “These are 70-year-old patients on average, and you can see here 10-year ipsilateral stroke [rates],” he said, pointing to a slide illustrating relevant data. “Six percent in CREST, 6% in ACST-2. Remember, these patients came in with risk factors for stroke, high-grade stenosis, and that is 0.6% per year in this patient population. In the United States, for a random population in that age group, any stroke is 0.6% per year. This is an achievement.”
Brott continued: “What about current standards of non-invasive care? With people that have high-grade carotid stenosis and all the attendant risks of that disease, we do not know. And that is why the medical arm is actually the experimental arm in CREST-2.”
Brott also addressed Abbott’s statement that crucially needed trials will be difficult, if not impossible, to complete. “CEA enrollment in CREST-2 is complete,” he argued. “With CAS enrollment, we have only got about 80 or so patients to go.” Finally, he focused on Abbott’s claim over the CMS funding changes and increased usage. “Atherosclerosis is getting less and less common,” he retorted. “We are seeing fewer and fewer patients. We don’t know what is going to happen, but the changes in medical care are decreasing the numbers of patients with asymptomatic carotid stenosis.”
Stepping up to the VEITH 2023 debate podium after Brott, Abbott hit back, standing behind her recent writings with which Brott took issue. “In a major coup for bad medicine, U.S. Medicare has just announced it finds coverage for carotid stenting is reasonable and necessary for beneficiaries with symptomatic carotid stenosis of at least 50%, or asymptomatic stenosis of at least 70%,” she told the gathering. “This is greatly expanded coverage, including to average-surgical-risk patients. Further CMS—or third-party—accreditation or certification are no longer required. Facilities will now be responsible for their own procedural standards and training. Formal shared decision-making with beneficiaries has been encouraged. Facility oversight committees are encouraged to apply published guidelines.”
She called the move “a major breach of U.S. Medicare’s duty of care to the public—and there are many reasons for this.” First, Abbott said stenting “does cause more harm” than CEA. “In randomized trials, stenting caused more 30-day periprocedural stroke, death and heart attack in symptomatic patients, and in a meta-analysis of randomized trials stenting caused more 30-day periprocedural stroke and death in asymptomatic patients,” she continued. “Stenting was worse with risk-factor long-term stroke rates, and registry stroke shows similar, if not worse, results with stenting compared to endarterectomy.”
Furthermore, Abbott argued that “there is no reliable way to measure carotid stenosis—methods have changed and tend to overestimate the degree of narrowing. Guidelines worldwide are outdated and encourage procedural overuse. Procedural outcomes are highly dependent on operator expertise, and removal of externally applied standards will encourage harm.”
Abbott also addressed the case of TCAR. “It has not been compared to endarterectomy,” she said, “and its efficacy has not been assessed and compared to non-invasive care alone, so there is no procedural indication and, in fact, there is no current procedural benefit for any carotid artery so-called revascularization procedure compared to current standards, particularly of best practice non-invasive care alone.”
At the debate conclusion, the VEITH 2023 audience overwhelming voted to back the arguments put forward by Abbott.
