Society for Vascular Surgery duplex ultrasound surveillance guidelines are safe and cost effective for transcarotid artery revascularization

Carotid duplex ultrasound (CDUS) examination is used in the long-term surveillance after transcarotid artery revascularization (TCAR). The objective of this study was to evaluate the usefulness and cost effectiveness of post-TCAR CDUS surveillance regimens in monitoring for in-stent restenosis (ISR) and associated stroke risk at a single-center community institution.

CDUS data were collected retrospectively from patients who had undergone TCAR between January 2017 and January 2023. ISR >50% was defined as a peak systolic velocity (PSV) of >220 cm/s and an internal carotid artery (ICA) to common carotid velocity ratio of >2.7. ISR >80% was defined as a PSV of >340 cm/s and an ICA/common carotid artery ratio of >4.15. Study outcomes included incidences of ISR, reintervention, transient ischemic attacks (TIAs), strokes, and mortality. A Kaplan-Meier survival analysis was done to calculate the rates of freedom from ISR.

During the study period, 108 TCAR stents were deployed in 104 patients. Eight patients were excluded in analysis or lost to follow-up. Preoperatively, 62% of patients had >80% stenosis, and 39% were symptomatic. No intraprocedural complications were noted. One patient suffered an immediate postoperative dissection. Eight stents (8%) experienced ISR progression from <50% to >50%. Three of the eight had further ISR progression to >80%. One patient had high-grade ISR and a contralateral ICA occlusion that warranted reintervention. There were no occurrences of postoperative TIAs, strokes, or TCAR-related deaths. Rates of freedom from ISR progression from <50% to >50% were 97.4%, 95.9%, 90.9%, 88.2%, and 88.2% at 6, 12, 24, 36, and 42 months, respectively. Rates of freedom from ISR >80% were 100%, 100%, 98.5%, 95.5%, and 95.5% at the same time points. Patients with >50% ISR tended to be females with hyperlipidemia. In addition, they had higher average lesion lengths and lower rates of postdilation balloon angioplasty. The 5-year estimated surveillance cost in this cohort using the Society for Vascular Surgery 2022, and 2018 guidelines, as well as our current protocol would be $113,853, $221,382, and $193,207, respectively.

This study revealed a low incidence of ISR progression, as well as no TIA, stroke, or TCAR-related deaths, highlighting the safety and efficacy of TCAR. Post-TCAR CDUS examination using the updated Society for Vascular Surgery guidelines are safe and cost effective. Patients with contralateral occlusion or stenosis, or who have significant risk factors, should have more frequent surveillance regimens.