From the Guidelines
Transcarotid Artery Revascularization (TCAR) is indicated for patients with carotid artery stenosis who are at high risk for traditional carotid endarterectomy (CEA), specifically those with symptomatic ≥50% stenosis or asymptomatic ≥70% stenosis and anatomical or physiological high-risk factors, as it may be associated with a lower risk of stroke or death compared to transfemoral carotid artery stenting (tfCAS) 1. The indications for TCAR include:
- Symptomatic patients with ≥50% stenosis or asymptomatic patients with ≥70% stenosis
- Anatomical or physiological high-risk factors, such as:
- Previous neck radiation
- Prior neck surgery
- Contralateral carotid occlusion
- High lesions above C2
- Low lesions below the clavicle
- Severe cardiac or pulmonary disease
- Age >80 years Contraindications for TCAR include:
- Severe vessel tortuosity
- Heavy calcification that prevents sheath placement
- Previous ipsilateral carotid endarterectomy
- Common carotid artery diameter <6mm
- Acute stroke within 48 hours
- Known hypersensitivity to device materials
- Untreatable bleeding disorders
- Inability to tolerate blood flow reversal due to inadequate collateral circulation The procedure is preferred over traditional tfCAS because it reduces embolic stroke risk through its unique flow reversal system, which diverts potential emboli away from the brain during the intervention, as suggested by recent studies 1. TCAR has specific anatomical considerations, including the requirement of a disease-free common carotid artery, and patients in TCAR studies may be somewhat different than those in CEA or tfCAS studies 1. Recent data from the VQI TCAR Surveillance Project registry suggest that TCAR may be associated with a lower risk of stroke or death in comparison with 1st generation stent tfCAS and similar in-hospital stroke or death rate when compared with CEA 1. However, randomized or large multi-centre prospective trials with independent neurological and radiographic adjudication are ideally needed to compare TCAR with tfCAS, CEA, and/or best medical therapy strategies not only in high surgical risk patients but also in average-risk patients 1.
From the Research
Indications for TCAR
- Symptomatic carotid stenosis: TCAR is indicated for patients with symptomatic carotid stenosis, particularly those with high-risk features for surgery 2, 3, 4, 5.
- Asymptomatic carotid stenosis: Although less common, TCAR may be considered for asymptomatic patients with severe carotid stenosis (>70%) 3.
- High-risk patients: TCAR is a viable option for patients who are at high risk for carotid endarterectomy (CEA) or transfemoral carotid artery stenting (TF-CAS) due to comorbidities or anatomical characteristics 2, 3, 4.
Contraindications for TCAR
- Severe carotid tortuosity or calcification: Patients with severe carotid tortuosity or calcification may not be suitable for TCAR due to the increased risk of complications 6.
- Contralateral carotid occlusion: The presence of a contralateral carotid occlusion may increase the risk of stroke during TCAR, making it a relative contraindication 4.
- Unfavorable aortic arch anatomy: Patients with unfavorable aortic arch anatomy, such as a type III arch, may be at higher risk for complications during TCAR 6.
Special Considerations
- Cranial nerve injury: TCAR has been associated with a lower risk of cranial nerve injury compared to CEA 6.
- Flow reversal: The use of flow reversal during TCAR may reduce the risk of antegrade embolic stroke 6.
- Operator experience: The success and safety of TCAR depend on the operator's experience and skill level 2, 3, 4, 5, 6.