Transcarotid Artery Revascularization vs Carotid Artery Stenting: Systematic Review with ☸️SAIMSARA.

DOI: 10.62487/saimsara1247267

Author: saimsara.com

Review Stats

Generated: 2025-11-24 22:51:09 CET
Plan: Premium (expanded craft tokens; source: Europe PMC)
Source: Europe PMC
Scope: Titles/Abstracts (tiab)
Keyword Gate: Fuzzy (≥60% of required terms, minimum 2 terms matched in title/abstract)
Total Abstracts/Papers: 76
Downloaded Abstracts/Papers: 76
Included original Abstracts/Papers: 65
Total study participants (naïve ΣN): 33220

Outcome-Sentiment Meta-Analysis (OSMA): (LLM-only)
Frame: Head-to-Head (A vs B) • Source: Europe PMC
Comparators: A = TCAR; B = CAS
Outcome: Outcome Typical timepoints: peri/post-op, 30-day. Reported metrics: %, CI, p.
Common endpoints: Common endpoints: complications, mortality, functional.
Predictor: TCAR vs CAS — procedures/interventions.

1) A favored (TCAR) — Outcome with TCAR vs CAS — [1], [5], [6], [8], [9], [10], [13], [14], [19], [20], [21], [24], [26], [27], [32], [38], [39], [42], [45], [46], [48], [53], [55], [56], [58] — ΣN=20638
2) B favored (CAS) — Outcome with TCAR vs CAS — [49] — ΣN=40
3) Neutral (no difference) — Outcome with TCAR vs CAS — [2], [3], [4], [7], [11], [12], [15], [16], [17], [18], [22], [23], [25], [28], [29], [30], [31], [33], [34], [35], [36], [37], [40], [41], [43], [44], [47], [50], [51], [52], [54], [57], [59], [60], [61], [62], [63], [64], [65] — ΣN=12542

1) Introduction
Carotid artery stenosis represents a significant cerebrovascular pathology, leading to a substantial burden of stroke and related morbidity. Management strategies primarily involve medical therapy and revascularization procedures, including carotid endarterectomy (CEA), traditional transfemoral carotid artery stenting (TF-CAS), and the more recently introduced transcarotid artery revascularization (TCAR). While CEA has long been the gold standard, endovascular approaches like carotid artery stenting (CAS) offer less invasiveness. However, concerns regarding periprocedural stroke risk, particularly with TF-CAS, have prompted the development and adoption of TCAR, which incorporates direct carotid access with flow reversal for neuroprotection. The comparative safety and efficacy of TCAR versus conventional CAS, particularly TF-CAS, remain a critical area of investigation for optimizing patient outcomes and guiding clinical decision-making.

2) Aim
The aim of this paper is to systematically review and synthesize the current evidence comparing TCAR and CAS, with a focus on transfemoral TF-CAS and other endovascular approaches, for the treatment of carotid artery stenosis, evaluating their respective safety profiles, efficacy in preventing neurological events, and impact on patient-specific outcomes.

3) Methods
Systematic review with multilayer AI research agent: keyword normalization, retrieval & structuring, and paper synthesis (see SAIMSARA About section for details).

Bias: The majority of studies included are retrospective cohorts or mixed designs, with several lacking specified study type or directionality. This prevalence of observational studies inherently introduces a risk of selection bias, confounding, and potential for unmeasured confounders, limiting the ability to establish definitive causal relationships between intervention type and outcomes.

4) Results
4.1 Study characteristics
The included studies predominantly employed mixed, retrospective cohort, or cohort designs, with some lacking specified study design. Populations comprised patients with carotid artery stenosis, including asymptomatic, symptomatic, high-risk, octogenarian, and those with specific comorbidities like prior ipsilateral CAS or head and neck radiation. Sample sizes varied widely, from single case reports [2, 4, 33] to large cohorts exceeding 5,000 patients [5]. Follow-up periods ranged from in-hospital and 30-day perioperative assessments to longer-term evaluations at 6 months, 1 year, 3 years, and 5 years.

4.2 Main numerical result aligned to the query
Across multiple studies, the median perioperative stroke or death rate for TCAR was 2.3% (ranging from 0.7% to 3.6%) compared to 3.7% (ranging from 2.0% to 6.6%) for TF-CAS [10, 16, 17, 27, 32, 38, 48, 49]. This suggests TCAR is associated with a generally lower risk of perioperative stroke or death compared to TF-CAS. For instance, in asymptomatic patients, TCAR demonstrated a 3-year stroke risk of 5.1% (95% CI, 3.0%-7.1%) versus 9.2% (95% CI, 7.7%-10.7%) for TF-CAS [5]. Similarly, in symptomatic patients, TCAR's 3-year stroke risk was 16.6% (CI, 12.1%-20.9%) compared to 20.9% (CI, 17.5%-24.1%) for TF-CAS [5].

4.3 Topic synthesis

Stroke and Mortality Outcomes: TCAR consistently shows lower risks of perioperative stroke or death compared to TF-CAS, with adjusted hazard ratios for stroke after TF-CAS vs TCAR at 1.69 (95% CI, 1.25-2.28) for asymptomatic and 1.42 (95% CI, 1.17-1.73) for symptomatic patients over 3 years [5, 10, 13, 27, 32, 38, 42]. TCAR may also offer a long-term mortality benefit over CAS [1, 20].
Neuroprotection and Embolic Events: TCAR's dynamic flow reversal provides superior neuroprotection compared to distal embolic filters in other CAS approaches, leading to lower in-hospital stroke/death rates (1.6% vs 5.2%; OR, 0.35) [58]. TCAR is also associated with a lower risk of cerebral hyperperfusion syndrome (0.53% vs 1.1%) compared to CAS with distal embolic protection [9].
Procedural Efficiency and Safety: TCAR is associated with less intraoperative complexity than TF-CAS, including shorter operative time (64.3 ± 0.9 min vs 83.2 ± 2.6 min), lower radiation exposure (232.7 ± 19.1 mGys vs 769.9 ± 144.3 mGys), and reduced contrast volume (22.6 ± 0.4 mLs vs 75.2 ± 2.4 mLs) [48]. Technical success rates for TCAR are high (98%) with low local complications [65].
Patient-Specific Risk Factors and Eligibility: TCAR may be preferred for patients with prior head and neck radiation [26] or contralateral occlusion [23]. However, increasing carotid lesion calcification (51%-99%) is a significant risk factor for in-hospital stroke/death in both TF-CAS and TCAR [31], and female sex, older age, and higher BMI can be associated with TCAR ineligibility [37].
Pharmacological Management: Perioperative P2Y12 inhibitor use significantly decreases neurological events and mortality in both TCAR and TF-CAS [44]. Intraoperative protamine reduces bleeding complications in TCAR and TF-CAS [3], and is a protective factor against perioperative stroke/death in TCAR [4]. Renin-angiotensin-system blocking agents are also associated with decreased neurologic events in TCAR [45].
Long-term Outcomes and Reintervention: TCAR demonstrates favorable long-term outcomes, with lower hazard of longer-term reintervention compared to TF-CAS (HR: 2.31 for TFCAS vs TCAR) [4, 14]. However, younger patients undergoing CAS may have a higher likelihood of restenosis or occlusion at 1-year (4.7% vs 2.3% in older patients) [59].
Healthcare System and Cost Implications: Hospital reimbursement and profit margins are higher for TF-CAS than TCAR [36]. Physician preference for carotid artery stenosis management impacts overall stroke/death rates, with those performing CEA and TFCAS having higher rates (2.2%) compared to those performing CEA and TCAR (1.4%) [19].

5) Discussion
5.1 Principal finding
The median perioperative stroke or death rate for TCAR was 2.3% (range 0.7% to 3.6%) compared to 3.7% (range 2.0% to 6.6%) for transfemoral carotid artery stenting (TF-CAS), indicating a generally lower risk with TCAR [10, 16, 17, 27, 32, 38, 48, 49]. This finding suggests that TCAR offers a safer endovascular revascularization option compared to TF-CAS for patients with carotid artery stenosis.

5.2 Clinical implications

Preferred Endovascular Option: TCAR appears to be the safer endovascular option for carotid revascularization, demonstrating lower risks of stroke or death compared to TF-CAS in both asymptomatic and symptomatic patients, as well as in octogenarians [5, 10, 38, 42].
Enhanced Neuroprotection: The flow reversal mechanism of TCAR provides superior neuroprotection compared to traditional distal embolic filters in other CAS approaches, making it a strong consideration when embolic protection is paramount [58].
Tailored Treatment for High-Risk Patients: TCAR may be particularly beneficial for patients with specific high-risk characteristics, such as prior head and neck radiation or contralateral occlusion, where it demonstrates lower odds of stroke/death compared to CEA [23, 26].
Optimized Perioperative Management: The use of intraoperative protamine and perioperative P2Y12 inhibitors is associated with reduced complications in both TCAR and TF-CAS, emphasizing the importance of precise pharmacological protocols [3, 4, 44].
Procedural Efficiency Benefits: TCAR's reduced operative time, radiation, and contrast use [48] could improve patient safety, reduce hospital resource utilization, and potentially lead to faster recovery times.

5.3 Research implications / key gaps

Randomized Controlled Trials: Conduct large-scale randomized controlled trials directly comparing TCAR to TF-CAS and CEA to provide definitive evidence on long-term comparative effectiveness across diverse patient populations [21].
Long-term Outcome Comparisons: Investigate long-term outcomes (beyond 3-5 years) including stroke, death, restenosis, and quality of life, specifically comparing TCAR with various CAS approaches and CEA, especially in younger patients prone to restenosis [59].
Cost-Effectiveness Analyses: Perform comprehensive cost-effectiveness studies comparing TCAR, TF-CAS, and CEA, considering all direct and indirect costs, reintervention rates, and long-term quality of life impacts [36].
Personalized Treatment Algorithms: Develop and validate algorithms that integrate patient-specific risk factors, plaque morphology (e.g., calcification, lesion extension), and anatomical characteristics to guide individualized treatment selection for TCAR versus other CAS methods [31, 35, 62].
Pharmacological Regimen Optimization: Further research into optimal antiplatelet and antithrombotic regimens for TCAR and different CAS approaches, including the role of protamine and specific P2Y12 inhibitors, is warranted to minimize bleeding and thrombotic events [3, 4, 44, 61].

5.4 Limitations

Retrospective Study Designs — Many included studies are retrospective cohorts or mixed designs, introducing potential for selection bias and confounding that may influence reported outcomes.
Heterogeneity of CAS Procedures — "CAS" often encompasses various approaches (TF-CAS, TR-CAS, TCAS-DEP, FFRACAS), making direct comparisons challenging due to differing embolic protection strategies and access sites.
Variable Follow-up Durations — Follow-up periods range from in-hospital to 5 years, limiting consistent assessment of long-term efficacy and safety across all studies.
Lack of Randomized Trials — The absence of robust randomized controlled trials directly comparing TCAR to other revascularization methods (CEA, TF-CAS) prevents definitive conclusions about comparative effectiveness.
Sample Size Variability — Studies range from single case reports to large cohorts, affecting the statistical power and generalizability of findings, particularly for rare complications.

5.5 Future directions

Randomized Comparative Trials — Conduct large-scale randomized controlled trials comparing TCAR directly against TF-CAS and CEA.
Standardized Outcome Reporting — Standardize reporting of perioperative and long-term outcomes (stroke, death, MI, restenosis, reintervention, quality of life).
Plaque Morphology Research — Investigate the role of advanced imaging for plaque morphology and calcification in guiding personalized treatment decisions.
Cost-Effectiveness Studies — Perform comprehensive cost-effectiveness analyses comparing TCAR, TF-CAS, and CEA over extended follow-up periods.
Optimized Antithrombotic Protocols — Develop and validate evidence-based protocols for perioperative antithrombotic and antiplatelet therapy specific to TCAR and different CAS approaches.

6) Conclusion
The median perioperative stroke or death rate for TCAR was 2.3% (range 0.7% to 3.6%) compared to 3.7% (range 2.0% to 6.6%) for transfemoral carotid artery stenting (TF-CAS), indicating a generally lower risk with TCAR [10, 16, 17, 27, 32, 38, 48, 49]. This suggests TCAR offers a safer endovascular option for a broad range of patients with carotid artery stenosis, including those traditionally considered high-risk. However, the prevalence of retrospective study designs and heterogeneity in CAS approaches significantly limits the certainty of comparative conclusions. Clinicians should consider TCAR as a preferred endovascular option over TF-CAS for many patients, while future randomized trials are crucial to solidify these findings.

References
SAIMSARA Session Index — session.json

Figure 1. Publication-year distribution of included originals

Figure 1. Publication-year distribution of included originals

Figure 2. Study-design distribution of included originals

Figure 3. Study-type (directionality) distribution of included originals
Figure 3. Directionality distribution

Figure 4. Main extracted research topics

Figure 5. Limitations of current studies (topics)

Figure 6. Future research directions (topics)