What are the surgical steps for a Transcervical Carotid Artery Revascularization (TCAR) procedure?

Surgical Steps for Transcarotid Artery Revascularization (TCAR)

TCAR is performed through a small cervical incision with direct carotid access, utilizing dynamic flow reversal for cerebral protection during stent deployment. 1

Pre-Procedural Preparation

Antiplatelet Therapy:

• Dual antiplatelet therapy with aspirin 81-325 mg daily plus clopidogrel 75 mg daily must be administered for a minimum of 30 days before TCAR 2
• For clopidogrel-intolerant patients, ticlopidine 250 mg twice daily may be substituted 2
• Blood pressure control with antihypertensive medications is mandatory before the procedure 2

Baseline Assessment:

• Document clinical neurological examination within 24 hours before TCAR 2
• Perform baseline diffusion-weighted MRI when feasible to detect pre-existing ischemic lesions 3

Anesthesia Selection:

• Either general anesthesia or local/regional anesthesia produces equivalent clinical and technical outcomes 4
• Local/regional anesthesia permits real-time neurologic monitoring during flow reversal 4
• General anesthesia is used in 83% of cases and is increasingly preferred over time 4

Operative Technique

Step 1: Cervical Incision and Carotid Exposure

• Make a small transverse cervical incision above the clavicle to access the common carotid artery 1, 5
• This approach avoids aortic arch manipulation, which is the primary source of embolic complications in transfemoral carotid stenting 5

Step 2: Arterial Access and Sheath Placement

• Perform direct transcervical puncture of the common carotid artery 1
• Insert the arterial sheath for flow reversal system deployment 1

Step 3: Flow Reversal Initiation

• Establish dynamic (robust) flow reversal by clamping the common carotid artery proximally 2
• Connect the arterial sheath to the venous return system, typically via femoral venous access 1
• This creates retrograde flow in the internal carotid artery, directing embolic debris away from the brain 2, 1

Step 4: Lesion Crossing and Pre-Dilatation

• Cross the stenotic lesion with a guidewire under fluoroscopic guidance while maintaining flow reversal 1
• Perform balloon angioplasty if needed to facilitate stent delivery 1

Step 5: Stent Deployment

• Deploy the carotid stent across the stenotic segment while flow reversal remains active 1
• Double-layer micromesh stents may reduce plaque prolapse and embolization compared to single-layer stents 3
• Maintain flow reversal throughout stent deployment to capture any liberated embolic material 1

Step 6: Post-Dilatation and Flow Restoration

• Perform post-dilatation balloon angioplasty if residual stenosis exists 1
• Restore antegrade flow after confirming adequate stent expansion 1
• Average procedure time is 78 minutes, which is 33 minutes shorter than carotid endarterectomy 6

Step 7: Closure

• Remove the arterial sheath and achieve hemostasis 1
• Close the cervical incision in layers 5

Post-Procedural Management

Immediate Assessment:

• Perform neurological examination within 24 hours after TCAR 2, 1
• Obtain diffusion-weighted MRI at 48-72 hours post-procedure to detect subclinical ischemic lesions 3
• Continue dual antiplatelet therapy for minimum 30 days post-procedure 2

Surveillance:

• Perform noninvasive imaging (duplex ultrasound, CTA, or MRA) at 1 month, 6 months, and annually to assess patency 2
• Once stability is established, extend surveillance intervals 2

Technical Performance Metrics

Procedural Efficiency:

• Technical success rate is 99.7% 1
• Flow reversal time, fluoroscopy time, and contrast volume do not differ between anesthesia types 4
• Postoperative length of stay >1 day occurs in only 27% of cases 6

Common Pitfalls and Caveats

Patient Selection:

• TCAR is designed for patients at high surgical risk for carotid endarterectomy due to anatomic (44%) or physiological (32%) factors 1
• Symptomatic patients have higher stroke/death rates (2.5% vs 1.2% in asymptomatic patients) even with TCAR 2
• Recent stroke patients (within 48 hours) have increased odds of complications (OR 2.8) 2

Flow Reversal Considerations:

• Dynamic flow reversal is the primary mechanism of stroke reduction in TCAR 2
• Inadequate flow reversal may fail to protect against embolic events, particularly in symptomatic lesions 2
• Combining flow reversal with double-layer micromesh stents may optimize embolic protection 2, 3

Operator Experience:

• The majority (81.2%) of operators in the ROADSTER 2 study were TCAR-naïve at study initiation, yet achieved excellent outcomes 1
• Adherence to protocol and proper peri-procedural antiplatelet therapy are critical for optimizing outcomes 1
• Higher-volume operators (>12-40 cases) have lower complication rates 2

Anatomic Limitations:

• TCAR requires suitable cervical anatomy for direct carotid access 1
• Percutaneous transcarotid access (without surgical exposure) has complication rates approaching 20% and should be avoided outside emergent situations 2