Study: Transcarotid Stenting Has a Leg Up Over Femoral Approach

A technique developed to reduce stroke risk in carotid artery stenting was associated with better outcomes compared to the conventional transfemoral approach to the carotids, a study showed.

By avoiding the aortic arch with direct common carotid access and utilizing flow reversal prior to crossing the lesion, transcarotid artery revascularization (TCAR) led to fewer in-hospital events than transfemoral carotid stenting:

• Stroke or death: 1.6% vs 3.1% (RR 0.51, 95% CI 0.37-0.72)
• Stroke: 1.3% vs 2.4% (RR 0.54, 95% CI 0.38-0.79)
• Death: 0.4% vs 1.0% (RR 0.44, 95% CI 0.23-0.82)

Ipsilateral stroke or death at 1 year also favored TCAR over transfemoral carotid artery stenting (5.1% vs 9.6%, HR 0.52, 95% CI 0.41-0.66), according to a group led by Marc Schermerhorn, MD, of Beth Israel Deaconess Medical Center in Boston, reporting online in JAMA.

Historically, carotid stenting has been linked to increased periprocedural stroke risk compared with endarterectomy. The CREST trial showed investigators similar outcomes between stenting and surgery long term.

TCAR marries concepts from carotid stenting and carotid endarterectomy. The downside of this procedure appeared to be a higher risk of access site complication resulting in interventional treatment (1.3% vs 0.8%, RR 1.63, 95% CI 1.02-2.61), according to Schermerhorn’s group.

Transfemoral carotid artery stenting also led to more radiation (median fluoroscopy time 5 minutes vs 16 minutes, P<0.001) and more contrast used (median 30 mL vs 80 mL, P<0.001).

Odds of perioperative MI were no different between groups (0.2% vs 0.3%, RR 0.70, 95% CI 0.27-1.84).

Data for the study came from two registries: the Vascular Quality Initiative Transcarotid Artery Surveillance Project and the Transfemoral Carotid Stent Registry. Included were symptomatic and asymptomatic patients with carotid artery stenosis who had received TCAR (n=5,251) or transfemoral stenting (n=6,640) within the U.S. and Canada in 2016-2019.

Propensity score matching yielded 3,286 matched pairs for comparison. These patients averaged just under 72 years of age; more than 35% were women.

Schermerhorn’s team reported that TCAR procedures grew quickly in popularity, from 250 cases in 2016 to over 3,000 in 2018. By then, 46% of all carotid stenting procedures were performed via TCAR, they noted.

There was an interaction between presenting symptom status and treatment effect of TCAR.

Symptomatic patients gained a lower risk of in-hospital stroke or death with no significant uptick in bleeding complications from TCAR compared to transfemoral stenting. On the other hand, asymptomatic patients saw no reduction in in-hospital stroke or death; and while they shared overall bleeding complication rates with the transfemoral controls, they did require more bleeding reinterventions following TCAR.

“However, the study may have been underpowered to detect an association given the overall low event rates in asymptomatic patients,” Schermerhorn and colleagues cautioned.

Other limitations of the study include its observational nature, which precluded any causal inferences and left room for possible confounding. In addition, stroke was assessed by neurological symptoms. With no formal neurologic testing or imaging, there was a possibility of ascertainment bias, the authors acknowledged.

In the ROADSTER study, TCAR with the Enroute transcarotid stent resulted in a 1.4% stroke rate at 30 days, the lowest yet reported for a prospective study of carotid artery stenting.