Stenting or Surgery for Patients With Carotid Artery Stenosis?

While it has been up for debate whether a catheter-based minimally invasive stenting procedure or open surgery is the best treatment for asymptomatic severe carotid artery stenosis, researchers said there is no wrong answer.

In the ACST-2 trial, non-procedural fatal or disabling stroke occurred in 2.5% of patients in both groups — those assigned to carotid stenting and those who underwent carotid endarterectomy, for a rate ratio (RR) of 0.98 (95% CI 0.64-1.48, P=0.91) over 5 years of follow-up, reported Alison Halliday, MD, of the University of Oxford in England, during a press conference for the virtual European Society of Cardiology (ESC) congress. The study was published simultaneously in The Lancet.

Any non-procedural stroke occurred in 5.3% of the stenting group compared with 4.5% of the endarterectomy patients (RR 1.16, 95% CI 0.86-1.57, P=0.33), she added.

A meta-analysis of this trial and all other major trials of carotid stenting versus carotid endarterectomy yielded a similarly non-significant result for any stroke (RR 1.11, 95% CI 0.91-1.32, P=0.21).

“We have shown that, for patients with a severely narrowed carotid artery, stenting and surgery have similar effects on the chances of having a disabling or fatal stroke. The risk [of death and disabling stroke] from each procedure is about 1%. After that, however, the annual risk over the next 5 or more years is halved, from 1% down to 0.5% per year,” Halliday said.

Previous studies have shown that providing good medical treatment and then adding endarterectomy halves the risk of stroke in these patients, she noted.

ACST-2 is the largest trial to compare the long-term effects with stenting versus endarterectomy on stroke in asymptomatic patients with a severely narrowed carotid artery. The study was initiated to look at the long-term results with the two techniques, since most studies have been of short duration. Participants are being followed out to 10 years.

Severe carotid artery narrowing was defined as a ≥60% reduction in diameter on ultrasound found by chance, with no recent stroke or other neurological symptoms. While participants were in need of stenting or surgery, physicians were uncertain about which procedure was preferable.

“A lot of times, there really isn’t that much choice,” Halliday noted. Factors like the size and position of the lesion may make stenting less of a viable option, she suggested.

Halliday’s team enrolled 3,625 patients from 130 centers in 33 countries. Participants were randomly assigned on a 1:1 basis to either stenting or surgery and were followed for an average of 5 years.

The main outcomes of the study were 5-year non-procedural stroke, subdivided by severity, as well as procedural risks (morbidity and mortality within 1 month after the procedure).

Of patients who had a disabling stroke or died within 30 days, 15 were in the stenting group and 18 were in the surgery group (about 1% of each group). Two percent had a non-disabling procedural stroke (48 with stenting and 29 with surgery).

“Stenting of carotid arteries has not been utilized to a large extent in most countries in similar circumstances. This study suggests that perhaps stenting is an alternative to surgical procedures,” Stefan James, MD, of Uppsala University in Sweden, told MedPage Today.

“We really don’t get guidance on a patient level as to which procedure we should use, so I am sure that we need more trials that will teach us how to select patients for one procedure over the other,” he said. “The authors note that the physicians performing these procedures are competent, and that is something we have to interrogate in our institutions and our hospitals — what is the experience and competence in performing surgery versus stenting because these are very different types of procedures.”

“It gives me lots of hope that in the future we can better select patients for one procedure or the other and physicians need to make sure that they are competent and have experience with both types of procedures. From the patient’s perspective, I would guess that most patients would welcome a procedure that is less invasive. But obviously there is much more we need to learn,” he added.