Transcarotid Artery Endovascular Revascularization

Transcarotid Artery Endovascular Revascularization

Anesthesia type
Airway
Lines and access
Monitors
Primary anesthetic considerations
Preoperative
Intraoperative
Postoperative
Article quality
Editor rating	Unrated
User likes	2

Also referred to as a TCAR, a transcarotid artery endovascular revascularization is an alternative to carotid endarterectomy for the management of carotid stenosis in patients who are determined to be poor open repair candidates based on high surgical risk or lesion location (distal lesions). Transcarotid artery revascularization (TCAR) is an alternative to trans-femoral stenting and is meant to decrease the risk for micro-embolic strokes through flow reversal through the carotid during stent placement (see below).

Goal: Restoring laminar blood flow through a stenotic carotid artery narrowed by atherosclerotic or neointimal hyperplastic disease.

Overview

Surgical procedure:

The common carotid artery (CCA) is exposed via a small incision superior to the clavicle.

A flexible sheath is inserted into the CCA proximal to the lesion being stented and the distal end (outside the vessel) is connected to a flow reversal system (FRS).

At the same time the femoral vein is also being accessed either percutaneously or via surgical exposure, and a 2nd flexible sheath is inserted. The extraluminal end of the femoral sheath is attached to the other end of the flow reversal system (FRS).

Once connected blood flow from the high pressure CCA to the low pressure femoral vein through the FRS. After flow reversal wires are threaded past the lesion, if indicated pre-dilation of the vessel with balloon angioplasty occurs at this time, followed by deployment of the intralumenal stent. The FRS acts as a filter removing any plaques or disrupted intralumenal, decreasing the risk of micro-embolic strokes.

After successful placement, flow reversal is turned off and blood flow resumes in its normal direction. Sheaths removed and arteriotomy closed.

Video with overview of steps: TCAR | TransCarotid Artery Revascularization Procedure Narrated Animation | Silk Road Medical | https://www.youtube.com/watch?v=MI2s4rv0dJA

Indications:

Stent placement is preferred to carotid endarterectomy if the patient have ANY of a number of comorbid medical disease or anatomical factors (see below) that would complicate the hemodynamic management intraoperatively putting the patient at elevated risk for CV complications (hemodynamic instability / vasoplegia, MI, stroke, arrhythmia, etc) or surgical/airway access.

Medical:

• Age > 75
• Congestive Heart Failure
• LVEF < 35%
• >2 diseased coronaries w/ 70% stenosis
• Unstable angina or abnormal stress test
• MI within 6 weeks
• Need for additional open heart surgery
• Need for major surgery (including vascular)
• Uncontrolled diabetes
• Severe pulmonary disease

Anatomic:

• Prior head/neck surgery or irradiation
• Spinal immobility  
• Restenosis post carotid endarterectomy (CEA)
• Surgically inaccessible lesion
• Laryngeal palsy; Laryngectomy
• Permanent contralateral cranial nerve injury
• Contralateral occlusion
• Severe tandem lesions
• Bilateral stenosis requiring treatment

Preoperative management

Patient evaluation:

Assess for the listed conditions/diseases above.

System	Considerations
Airway	Neck mobility, ability to tolerated surgical positioning. Prior neck radiation
Neurologic	Baseline neurologic exam, post operatively at risk for micro-embolic strokes. Assess if carotid stenosis is symptomatic (see below)
Cardiovascular	Exercise tolerance, assess for listed cardiovascular comorbid diseases above
Pulmonary	Exercise tolerance
Gastrointestinal
Hematologic	Ensure taking dual anti-platelet therapy per surgical team's directions
Renal	Current volume status, relative hypovolemia may adversely affect ability to induce HTN during flow reversal
Endocrine	Check BG
Other

- Symptomatic Carotid Stenosis: Stroke or TIA referable to the appropriate carotid artery distribution within the previous six months AND carotid stenosis > 50%.

- Asymptomatic Carotid Stenosis: Atherosclerotic narrowing of the extracranial ICA (>80%) without recent stroke or TIA (Of note, vertigo and syncope are not typical manifestations)

Labs and studies

All carotid surgeries are considered high-risk & pre-surgical testing should follow AHA/ACA guidelines for high-risk noncardiac surgery.

• CBC, electrolytes, creatinine, PT/INR/aPTT
• T&C; consider requesting to have 2 units of pRBC on hold
• 12 lead EKG
• Consider Stress Test (exercise or pharmacology) if:
  • Poor or unknown functional status
  • Calculated risk for major adverse cardiovascular events (MACE) is >1% on the VQI or NSQIP calculator
• TTE if concerned for CHF, pulmonary HTN, or valvular disease (may impair ability to safely induce needed hypertension intraoperatively)
• Per surgical team's preference either CT angiogram v Carotid ultrasound to define anatomy

Operating room setup

TCAR can be preformed under GA or MAC with regional anesthesia

If planning to use MAC, have supplies for full conversion to GA

Have appropriate vasoactive medication available quickly titrate blood pressure intraoperatively

- Push Medications: consider Nitroglycerin, Epinephrine, Phenylephrine

- Prepared Drips: Norepinephrine (or preferred short acting pressor), can consider supplies for vasodilatory drip in room

Run lines & monitors outside of fluoroscopy path to optimize surgical field

Regional and neuraxial techniques

Superficial Cervical Plexus Block

- With block procedure can be preformed with MAC

- Benefit in GA cases by decreasing opioid requirement, allows for more rapid neurologic assessment postoperatively

Intraoperative management

Monitoring and access

- Standard ASA monitors, 5 lead EKG

- Pre-induction arterial line

- PIV x 2 (note vasoactive medications will be in PIVs, make sure lines are stable/running well)

- Cerebral oximetry to monitor adequacy of collateral circulation via the Circle of Willis during flow reversal

- Intraoperative ACT monitoring during heparinization (target 250-350; verify goal with surgical team)

Induction and airway management

If planning on MAC with natural airway & superficial cervical plexus block, consider sedation with remifentanil infusion

Positioning

Supine with head turned contralateral to site of planned procedure

Postoperative management

Potential complications

- Micro-embolic stroke; check neurologic exam

-

Procedure variants

	Variant 1	Variant 2
Unique considerations
Position	Supine
Surgical time
EBL
Postoperative disposition
Pain management
Potential complications

References

1.) Columbo JA, Martinez-Camblor P, O’Malley AJ, et al. Association of Adoption of Transcarotid Artery Revascularization With Center-Level Perioperative Outcomes. JAMA Netw Open. 2021;4(2):e2037885. doi:10.1001/jamanetworkopen.2020.37885

2.) Ankam A, Kinthala S, Madabhushi P. Anesthetic Considerations for Transcarotid Artery Revascularization: Experience and Review of Forty Cases From a Single Medical Center. Cureus. 2020 Dec 24;12(12):e12250. doi: 10.7759/cureus.12250. PMID: 33505816; PMCID: PMC7822093.

3.) Silk Road Medical. TCAR surveillance project. Accessed January 1, 2020. https://silkroadmed.com/tcar-surveillance-project/