Evaluation of Robotic-Assisted Carotid Artery Stenting in a Virtual Model Using Motion-Based Performance Metrics

PURPOSE

Robotic-assisted carotid artery stenting (CAS) cases have been demonstrated with promising results. However, no quantitative measurements have been made to compare manual with robotic-assisted CAS. This study aims to quantify surgical performance using tool tip kinematic data and metrics of precision during CAS with manual and robotic control in an ex vivo model.

MATERIALS AND METHODS

Transfemoral CAS cases were performed in a high-fidelity endovascular simulator. Participants completed cases with manual and robotic techniques in 2 different carotid anatomies in random order. C-arm angulations, table position, and endovascular devices were standardized. Endovascular tool tip kinematic data were extracted. We calculated the spectral arc length (SPARC), average velocity, and idle time during navigation in the common carotid artery and lesion crossing. Procedural time, fluoroscopy time, movements of the deployed filter wire, precision of stent, and balloon positioning were recorded. Data were analyzed and compared between the 2 modalities.

RESULTS

Ten participants performed 40 CAS cases with a procedural success of 100% and 0% residual stenosis. The median procedural time was significantly higher during the robotic-assisted cases (seconds, median [interquartile range, IQR]: 128 [49.5] and 161.5 [62.5], p=0.02). Fluoroscopy time differed significantly between manual and robotic-assisted procedures (seconds, median [IQR]: 81.5 [32] and 98.5 [39.5], p=0.1). Movement of the deployed filter wire did not show significant difference between manual and robotic interventions (mm, median [IQR]: 13 [10.5] and 12.5 [11], p=0.5). The postdilation balloon exceeded the margin of the stent with a median of 2 [1] mm in both groups. Navigation with robotic assistance showed significantly lower SPARC values (-5.78±3.14 and -8.63±3.98, p=0.04) and higher idle time values (8.92±8.71 and 3.47±3.9, p=0.02) than those performed manually.

CONCLUSIONS

Robotic-assisted and manual CAS cases are comparable in the precision of stent and balloon positioning. Navigation in the carotid artery is associated with smoother motion and higher idle time values. These findings highlight the accuracy and the motion stabilizing capability of the endovascular robotic system.

CLINICAL IMPACT

Robotic assistance in the treatment of peripheral vascular disease is an emerging field and may be a tool for radiation protection and the geographic distribution of endovascular interventions in the future. This preclinical study compares the characteristics of manual and robotic-assisted carotid stenting (CAS). Our results highlight, that robotic-assisted CAS is associated with precise navigation and device positioning, and smoother navigation compared to manual CAS.

Drug-Coated Balloon Angioplasty for Carotid Artery In-Stent Restenosis: Case Series

OBJECTIVES

Few case reports have demonstrated promising results of drug-coated balloons (DCBs) as an emerging management for carotid artery in-stent restenosis (CAISR). Herein, we report 6 cases of CAISR which were treated with a DCB with or without new stent deployment.

BACKGROUND

Carotid artery in-stent restenosis is a high-risk condition with an estimated incidence rate that varies widely from 6% to 40%. Several strategies are available now for the management of the CAISR including conventional balloon angioplasty, plaque modification balloon angioplasty, and new stent placement.

METHODS

A retrospective review of consecutive patients with a diagnosis of severe CAISR at Baylor Scott & White The Heart Hospital Plano from 2011 to 2021 was performed. This study was approved by the Baylor Scott & White Research Institute institutional review board.

RESULTS

Six patients underwent DCB angioplasty with or without stent placement under an embolic protection device. Resolution of CAISR was achieved in all cases with 0% to 10% residual stenosis in all cases. Following the procedure, 1 patient had a brief episode of syncope with balloon inflation with immediate recovery on deflation of the balloon. There were otherwise no significant neurological or cardiac events prior to discharge. All patients were asymptomatic at their follow-up visit with no neurological or cardiac events reported at 12, 24, and 36 months following the procedure.

CONCLUSION

While CAISR treatment remains a challenging condition, our study shows that the use of DCB with or without stent placement is a feasible and promising treatment option when compared with other conventional treatment options.

CLINICAL IMPACT

Carotid artery in-stent restenosis treatment remains a challenging condition. Our study shows that the use of drug coated balloon with or without stent placement is a feasible and promising treatment option when compared with current conventional treatment options.

Determinants of Mortality and Mid-Term Outcomes After Transcarotid Artery Revascularization and Transfemoral Carotid Artery Stenting

OBJECTIVES

The potential benefit of transcarotid artery revascularization (TCAR) over transfemoral carotid artery stenting (tfCAS) has been studied in the perioperative period with lower rates of stroke and death; however, data on mid-term outcomes are limited. We aimed to evaluate 3-year outcomes after TCAR and tfCAS and determine the primary predictors of 30-day and 1-year mortality following TCAR.

METHODS

Data from the Vascular Quality Initiative for patients undergoing TCAR or tfCAS from January 2016 to December 2022 were analyzed. 1:1 propensity score matching using the nearest-neighbor method was used to adjust baseline demographics and clinical characteristics. Kaplan-Meier survival analysis and Cox Proportional Hazard Regression were used to evaluate long-term outcomes. Iterative stepwise multiple logistic regression analysis and Cox Proportional Hazard Regression were used to identify predictors of 30-day and 1-year mortality, respectively, based upon preoperative, intraoperative, and postoperative factors.

RESULTS

A total of 70 237 patients were included in analysis (TCAR=58.7%, tfCAS=41.3%). Transcarotid artery revascularization patients were older and had higher rates of comorbid conditions and high-risk medical and anatomic features than tfCAS patients. Propensity score matching yielded 22 322 pairs with no major differences between groups except that TCAR patients were older (71.6 years vs 70.8 years). At 3 years, TCAR was associated with a 24% reduction in hazard of death compared with tfCAS (hazard ratio [HR]=0.76, 95% confidence interval [CI]=0.71-0.82, p<0.001), for both symptomatic and asymptomatic patients. This survival advantage was established in the first 6 months (HR=0.59, 95% CI=0.53-0.62, p<0.001), with no difference in mortality risk from 6 months to 36 months (HR=0.95, 95% CI=0.86-1.05, p=0.31). Transcarotid artery revascularization was also associated with decreased hazard for 3-year stroke (HR=0.81, 95% CI=0.66-0.99, p=0.04) and stroke or death (HR=0.81, 95% CI=0.76-0.87, p<0.001) compared with tfCAS. The top predictors for 30-day and 1-year mortality were postoperative complications. The primary independent predictor was the occurrence of postoperative stroke.

CONCLUSIONS

Transcarotid artery revascularization had a sustained mid-term survival advantage associated over tfCAS, with the benefit being established primarily within the first 6 months. Notably, our findings highlight the importance of postoperative stroke as the primary independent predictor for 30-day and 1-year mortal.

CLINICAL IMPACT

The ongoing debate over the superiority of TCAR compared to tfCAS and CEA has been limited by a lack of comparative studies examining the impact of pre-operative symptoms on outcomes. Furthermore, data are scarce on mid-term outcomes for TCAR beyond the perioperative period. As a result, it remains uncertain whether the initial benefits of stroke and death reduction observed with TCAR over tfCAS persist beyond one year. Our study addresses these gaps in the literature, offering evidence to enable clinicians to assess the efficacy of TCAR for up to three years. Additionally, our study seeks to identify risk factors for postoperative mortality following TCAR, facilitating optimal patient stratification.

Preoperative Use of Statins in Carotid Artery Stenting: A Systematic Review and Meta-analysis

PURPOSE

To determine through meta-analysis whether administration of statins before carotid artery stenting (CAS) is associated with fewer periprocedural adverse events.

METHODS

All randomized and observational English-language studies of periprocedural statin administration prior to CAS that reported the outcomes of interest (stroke, transient ischemic attack, myocardial infarction, and death at 30 days) were included in a random-effects meta-analysis. The I² statistic was used to assess heterogeneity. Meta-regression analysis was performed to determine whether an association of statin treatment with risk of outcome events was influenced by other trial-level baseline characteristics of statin-treated and untreated patients.

RESULTS

Eleven studies comprising 4088 patients were included. Patients who received statins prior to CAS had a significantly lower risk of stroke (OR 0.39, 95% CI 0.27 to 0.58, p<0.01; I²=0%) and death (OR 0.30, 95% CI 0.10 to 0.96, p=0.042; I²=0%). Statin use was not associated with a reduced risk of transient ischemic attack or myocardial infarction. In meta-regression analysis, other trial-level baseline characteristics had no significant influence on the association of statin treatment with death or stroke.

CONCLUSION

Statin therapy prior to CAS is associated with decreased risk of perioperative stroke and death without any effect on the rates of transient ischemic attack or myocardial infarction.