Duplex Ultrasound Surveillance after Transcarotid Artery Revascularization (TCAR) in Clinical Practice

Surveillance and risk factors for early restenosis following transcarotid artery revascularization

OBJECTIVE

Restenosis after transcarotid artery revascularization (TCAR) is a known complication. When identified in the early postoperative period, it may be related to technique. We evaluated our TCAR experience to identify potentially modifiable factors impacting restenosis.

METHODS

This is a single-institution, retrospective review of patients undergoing TCAR from November 2017 to July 2022. Restenosis was defined as >50% stenosis on duplex ultrasound (DUS) examination or computed tomographic angiography (CTA). Continuous variables were compared using Kruskal-Wallis's test. Categorical variables were compared using the Fisher's exact test.

RESULTS

Of 61 interventions, 11 (18%) developed restenosis within the median follow-up of 345 days (interquartile range, 103-623 days). Among these patients, 82% (9/11) had >50% stenosis, and 18% (2/11) had >80% stenosis. Both patients with high-grade restenosis were symptomatic and underwent revascularization. Diagnosis of post-TCAR restenosis was via DUS examination in 45% (5/11), CTA in 18% (2/11), or both CTA/DUS examination in 36% (4/11). Restenosis occurred within 1 month in 54% (6/11) and 6 months in 72% (8/11) of patients. However, three of the six patients with restenosis within 1 month had discordant findings on CTA vs DUS imaging. Patient comorbidities, degree of preoperative stenosis, medical management, balloon size, stent size, lesion characteristics, and predilatation angioplasty did not differ. Patients with restenosis were younger (P = .02), had prior ipsilateral endarterectomy (odds ratio [OR], 6.5; P = .02), had history of neck radiation (OR, 18.3; P = .01), and lower rate of postdilatation angioplasty (OR, 0.11; P = .04), without an increased risk of neurological events.

CONCLUSIONS

Although post-TCAR restenosis occurred in 18% of patients, only 3% of patients had critical restenosis and required reintervention. Patient factors associated with restenosis were younger age, prior endarterectomy, and history of neck radiation. Although early restenosis may be mitigated by improved technique, the only technical factor associated with restenosis was less use of postdilatation angioplasty. Balancing neurological risk, this factor may have increased application in appropriate patients. Diagnosis of restenosis was inconsistent between imaging modalities; current surveillance paradigms and diagnostic thresholds may warrant reconsideration.

Thrombectomy and stenting of pseudoaneurysm from transcarotid artery revascularization

Background

Transcarotid artery revascularization (TCAR) is becoming an increasingly popular treatment of carotid stenosis. Despite this rapid adoption, little in the literature describes the associated complications of this procedure.

Case Description

We report a case of a left M1 large-vessel occlusion following treatment of symptomatic, high-grade carotid stenosis with a TCAR procedure approximately three weeks earlier. The initial angiography demonstrated a pseudoaneurysm in the left common carotid artery at the site of TCAR access with a distal clot in the carotid stent. The clot within the stent was aspirated, and a mechanical thrombectomy was performed with a combination of a stent-retriever and aspiration catheter for thrombolysis in cerebral infarction 2B revascularization.

Conclusion

The TCAR procedure offers a novel method for revascularization of carotid lesions; it does include its complications. While generally safe, access site complications such as pseudoaneurysms can always occur. Knowledge of this risk allows for appropriate surveillance and management should it occur.

Ultrasound Examination Without Axial Imaging is Sufficient for Preoperative Planning in Transcarotid Artery Revascularization (TCAR)

BACKGROUND

Duplex ultrasound is frequently used to determine the degree of carotid stenosis. However, axial imaging is typically obtained for operative planning for transcarotid artery revascularization (TCAR). We examined if ultrasound alone is sufficient before TCAR.

METHODS

Data from the Vascular Quality Initiative TCAR Surveillance Project registry between 2016 and 2021 was obtained. Patients were divided into 2 groups-those with preoperative ultrasound-alone (US) and those with additional axial imaging (AX). Perioperative outcomes were compared utilizing univariate Chi-square, independent t-test, multivariate logistic regression, and Kaplan-Meier analysis.

RESULTS

There were 3,418 patients identified: 682 in the US group and 2,736 in the AX group. More preoperative hypertension was reported in US (16.1% vs. 10.2%, P < 0.001) while cardiovascular disease (23% vs. 28.9%, P = 0.006) and prior ipsilateral stroke (22% vs. 32.7%, P = 0.002) were more prevalent in AX. More patients had history of contralateral carotid endarterectomy (13.6% vs. 16.7%, P = 0.035) or either ipsilateral (2.6% vs. 1.2%, P = 0.002) or contralateral (7.9% vs. 4.9%, P = 0.008) carotid artery stenting in the US group. Lower preoperative creatinine was reported in the US cohort (1.09 ± 0.01 vs. 1.18 ± 0.02, P < 0.001) while more were symptomatic in AX (28.2% vs. 36.2%, P < 0.001). There were no significant differences between lesion characteristics or operative decision making. A slightly higher total procedure time was seen in AX (73.7 ± 0.6 vs. 68.6 ± 1.3 min, P = 0.017). No differences were seen in perioperative transient ischemic attack/stroke or other immediate complications. At 2-year follow-up, both groups reported no significant differences in stroke-free survival (P = 0.750) and independent functional status remained near-identical (97.3% vs. 97.4%, P = 0.921). Kaplan-Meier analysis yielded no significant difference between mortality at 2 years (P = 0.563). Bivariate logistic regression modeling did reveal a statistically significant increase in likelihood of long-term ipsilateral stroke (odds ratio 1.77, P = 0.015) and non stroke-related complication in the postoperative period (odds ratio 4.81, P = 0.005). However, only a statistically significant relationship persisted in non-stroke complication when the model was controlled for between-group differences.

CONCLUSIONS

No significant differences in postoperative or long-term complications were noted with additional AX in preoperative TCAR planning. Thus, duplex ultrasound offers a safe and effective alternative for those with contraindication or axial imaging.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.