A durability study that looks at reintervention risk among patients treated with carotid endarterectomy (CEA) versus carotid artery stenting (CAS) procedures established that CEA demonstrated the lowest risk up to six months after surgery. A subgroup analysis between stenting procedures—transfemoral stenting versus transcarotid artery revascularisation (TCAR)—further showed the latter stenting modality was superior after six months.
The data were delivered during a Vascular Annual Meeting (VAM; 14–17 June, National Harbor, USA) plenary session by first author Shaunak Adkar (Stanford Medicine, Stanford, USA). The point here was to understand the as-yet lesser-understood nature of procedural durability, so explained senior author Jordan R Stern (Stanford Medicine, Stanford, USA) in an interview with Vascular Specialist ahead of this year’s meeting. “We do not really know about the durability of each of the procedures,” he said.
The study team used the Vascular Quality Initiative (VQI), matching it to Medicare claims via the Vascular Implant Surveillance and Implantation Network (VISION) database. They identified patients who had primary carotid revascularisation from December 2016 to December 2019. The primary outcome was ipsilateral reintervention, while secondary outcomes included stroke and mortality. After propensity matching, patients who underwent CEA and CAS were compared within six months following the index procedure, and from six months to three years separately. A separate propensity-matched analysis was then performed to compare transfemoral stenting and TCAR.
“Like many endovascular procedures, we had a presumption that reintervention may be significantly higher among stenting-type procedures versus endarterectomy—analogous to lower-extremity or aortic work,” Stern stated. “When we looked at reintervention, which was what we were primarily interested in, we found a difference between endarterectomy and all stenting. CEA was superior up to six months, but that was not maintained in the long run. Over time, the reintervention rates merge and it is no longer statistically significant.
“In terms of TCAR versus transfemoral stenting, I had the presumption that things would be equal. A stent is a stent and, once you get through the perioperative risk of transfemoral stenting, I thought that, probably in the long run, the stents would be equally durable. But, actually, we did not find that—we found that TCAR was associated with a lower risk of reintervention than transfemoral stenting. That was after six months. So, CEA is better than all stents within six months, and TCAR is better than transfemoral stenting after six months.”
The data were based on some 27,944 patients undergoing CEA (n=21,256) or CAS (n=6,688). After propensity matching, 4,705 patients were compared in each group. They showed an increased risk of reintervention within six months for CAS, with a hazard ratio (HR) of 1.97 (confidence interval [CI] 1.11–3.50; p<0.05), but not beyond (HR: 1.08; CI: 0.62-1.89; p=0.79).
The findings paint a broad picture, between well-defined perioperative outcomes and reintervention risk, according to Stern. “For me personally, transfemoral stenting has been relegated to a secondary procedure because of the perioperative stroke risk,” he noted. “I think, then, that when I am looking at durability, if reinterventions are lower with CEA within the first six months, that would probably push me towards CEA even more than I already am. The finding of TCAR being lower than transfemoral stenting I think provides more evidence that TCAR is a superior procedure in most ways compared to transfemoral stenting.”
Ultimately, “what we really want to know is what is good for patients long-term”, Stern added. To that end, further analyses carried out by the research team uncovered additional findings that were elaborated on in Adkar’s presentation at VAM 2023. “In the unmatched set, transfemoral stenting was an independent predictor of reintervention,” Stern commented. “And we did an additional analysis of TCAR versus CEA, since those seem to be the superior modalities, and did not find a difference.”
“CEA portends a lower risk of reintervention than CAS, particularly within the first six months after intervention,” presenting author Adkar summarised, shifting focus back to the core analysis. “We also confirm prior data suggesting lower rates of ipsilateral stroke and death with CEA compared to CAS. On subgroup analysis of stenting modalities, TCAR had a lower rate of reintervention than transfemoral stenting. CEA appears to be the most durable carotid revascularisation strategy, with TCAR being more durable among stenting procedures.”