Bradycardia During TCAR Procedure for Carotid Stenosis
Yes, patients can commonly experience bradycardia during Transcarotid Artery Revascularization (TCAR) procedures for carotid stenosis due to baroreceptor stimulation in the carotid sinus. 1
Mechanism and Frequency
Bradycardia during carotid interventions occurs due to:
- Direct mechanical stimulation of carotid sinus baroreceptors during balloon inflation and stent deployment
- Reflexive increased parasympathetic discharge and inhibition of sympathetic tone
- This baroreceptor reflex can lead to both bradycardia and hypotension
The incidence of bradycardia during carotid interventions is significant:
- Occurs in approximately 27-62% of carotid stenting procedures 2, 3
- More common in primary carotid lesions than in post-endarterectomy restenosis 4, 3
- Particularly prevalent in radiation-induced stenosis (78%) 2
Risk Factors
Several factors increase the risk of developing bradycardia during TCAR:
- Advanced age (>78 years) 3
- Compromised ejection fraction (<25%) 3
- Symptomatic carotid lesions 2
- Primary (vs. post-endarterectomy) stenosis 4, 3
- Proximity of stenosis to the carotid bifurcation 5
- Greater percentage of vessel dilation during the procedure 5
Management Recommendations
Preprocedural Management
- Prophylactic atropine administration (0.5-1mg IV) is recommended before balloon inflation or stent deployment to prevent bradycardia 1, 4
- Ensure adequate hydration and careful adjustment of antihypertensive medications before the procedure 1
- Consider placement of transcutaneous pacing pads for high-risk patients 1
Intraprocedural Management
- Continuous electrocardiogram and blood pressure monitoring throughout the procedure 1
- Immediate administration of atropine for symptomatic bradycardia if not given prophylactically
- For persistent bradycardia unresponsive to atropine, temporary transvenous pacing may be required 1
- For persistent hypotension, intravenous phenylephrine (1-10 mcg/kg/min) or dopamine (5-15 mcg/kg/min) should be available 1
Postprocedural Management
- Continue monitoring for at least 12 hours post-procedure, as delayed onset of bradycardia can occur in approximately 8% of patients 5
- For persistent hypotension, oral ephedrine (25-50mg orally, 3-4 times daily) may be useful 1
- Extended observation may be required for patients with persistent hemodynamic instability
Clinical Implications
- Persistent hypotension after carotid stenting is associated with increased risk of adverse clinical events 3
- Prophylactic atropine significantly reduces the incidence of bradycardia (9% vs 50%) and cardiac morbidity (0% vs 15%) compared to selective administration 4
- Patients with prior carotid endarterectomy have significantly lower risk of bradycardia (10% vs 33%) and hypotension (5% vs 32%) during subsequent carotid interventions 4, 3
Monitoring Duration
Post-procedural monitoring should continue for at least 12 hours, as new-onset bradycardia or hypotension can occur later than 6 hours after the procedure in approximately 8% of patients 5.