Summary & Overview
CPT 35691: Vertebral to Carotid Artery Anastomosis
CPT code 35691 represents an open vascular surgical procedure that exposes the vertebral artery, divides it, and anastomoses it to the carotid artery beyond an occlusive lesion to restore posterior cerebral blood flow. The code matters nationally because it describes a technically complex revascularization aimed at preventing ischemic events in patients with vertebrobasilar insufficiency or proximal vertebral artery occlusion, with implications for surgical capacity, hospital resource use, and specialty reimbursement.
Key payers in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise clinical context for the procedure, the typical site of service, and the service type. The publication provides benchmarks and coding guidance context, highlights common billing modifiers associated with complex surgical services, and summarizes payer coverage patterns where available.
This overview is intended for health policy analysts, hospital revenue cycle teams, and vascular surgery clinicians seeking a clear national summary of the code, its clinical purpose, and the areas to consider when reviewing reimbursement, utilization, and documentation practices. Data not available in the input will be noted where relevant.
Billing Code Overview
CPT code 35691 describes a vascular surgical procedure in which the provider fully exposes the vertebral artery, divides it, and anastomoses the artery to the carotid artery beyond a site of arterial blockage. The service is performed to improve arterial blood flow to the posterior circulation.
Service type: Open vascular bypass/anastomosis of vertebral to carotid artery
Typical site of service: Inpatient or outpatient hospital operating room; specialized vascular surgery center
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A typical patient is a 68-year-old male with symptomatic vertebrobasilar insufficiency characterized by recurrent transient ischemic attacks (dizziness, diplopia, gait instability) despite maximal medical therapy for atherosclerotic disease. Noninvasive vascular imaging (CT angiography or MR angiography) and digital subtraction angiography demonstrate high-grade stenosis or occlusion of the proximal vertebral artery with inadequate collateral flow. The vascular surgery or neurosurgery team schedules an operative revascularization: open exposure of the vertebral artery at the cervical V2–V3 segment, division of the diseased segment, and direct end-to-side or end-to-end anastomosis of the vertebral artery to the common or external carotid artery beyond the lesion.
Preoperative workflow includes vascular imaging review, antiplatelet and anticoagulation planning, informed consent discussing stroke risk and cranial nerve injury, and coordination with anesthesia for intraoperative neuromonitoring. Intraoperative steps include neck incision, careful dissection to expose the vertebral and carotid arteries, heparinization, temporary occlusion, arterial division and mobilization, vascular anastomosis (microsurgical technique), and hemostasis. Postoperative care includes neurologic monitoring in a step-down or intensive care setting, blood pressure control, antithrombotic management, and surveillance duplex or CTA to confirm patency.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | Unspecified |