35301

Thromboendarterectomy, including patch graft, if performed; carotid, vertebral, subclavian, by neck incision

The CPT code 35301 describes a thromboendarterectomy, which is a surgical procedure performed to remove atherosclerotic plaque from the inner lining of the carotid, vertebral, or subclavian arteries through an incision in the neck. This procedure is primarily indicated for patients with significant arterial stenosis who are at high risk for ischemic stroke or transient ischemic attacks (TIAs). The primary goal is to restore normal luminal diameter and blood flow to the brain by removing the obstructive plaque that could either block flow or act as a source of emboli. During the procedure, the patient is typically placed under general anesthesia. The surgeon makes an incision in the neck to gain access to the carotid sheath and the affected vessel. Once the artery is exposed and isolated, systemic heparin is administered to prevent clotting. The surgeon then places clamps on the artery to control blood flow. In many cases, a temporary internal shunt is placed to maintain cerebral perfusion while the artery is open. An arteriotomy is performed, and the surgeon meticulously dissects the plaque away from the vessel wall, focusing on the intima and media layers. After the plaque is removed, the vessel is flushed to ensure no debris remains. The arteriotomy is then closed, often using a patch graft (such as an autogenous vein, bovine pericardium, or synthetic material) to ensure the vessel remains widely patent and to minimize the risk of restenosis. The 35301 code specifically includes the placement of this patch graft if the surgeon deems it necessary. After flow is restored and hemostasis is confirmed, the neck incision is closed in layers.

Clinical Indications

  • Symptomatic carotid artery stenosis (greater than 50% diameter reduction)
  • Asymptomatic carotid artery stenosis (greater than 60-70% diameter reduction)
  • Recurrent transient ischemic attacks (TIAs) related to precerebral arterial disease
  • History of minor ischemic stroke with significant residual stenosis
  • Vertebral artery stenosis causing posterior circulation symptoms
  • Subclavian steal syndrome resulting in upper extremity or cerebral ischemia
  • Ulcerated atherosclerotic plaques in the carotid bulb

Procedure Steps

  1. Positioning the patient with the neck extended and rotated away from the operative side.
  2. Making a longitudinal incision along the anterior border of the sternocleidomastoid muscle.
  3. Careful dissection through the platysma and carotid sheath to expose the common, internal, and external carotid arteries.
  4. Identifying and protecting the vagus, hypoglossal, and laryngeal nerves.
  5. Administration of systemic heparin for anticoagulation.
  6. Application of vascular clamps to the common, internal, and external carotid arteries.
  7. Optional placement of an intraluminal shunt to maintain cerebral blood flow.
  8. Creation of a longitudinal arteriotomy over the plaque, extending into the internal carotid artery.
  9. Meticulous removal of the atherosclerotic plaque from the arterial wall.
  10. Tacking down of any distal intimal flaps to ensure a smooth transition zone.
  11. Closure of the arteriotomy, typically utilizing a patch graft (vein or synthetic).
  12. De-airing the vessel and sequential removal of clamps to restore blood flow.
  13. Confirmation of patency and hemostasis, followed by layered wound closure.

Coding Guidelines

  • 35301 is a unilateral procedure. If the procedure is performed on both the left and right sides during the same operative session, use modifier 50.
  • The placement of a patch graft (autogenous, prosthetic, or bovine) is included in code 35301 and should not be reported separately.
  • Intraoperative shunting is considered a component of the procedure and is not separately billable.
  • If the procedure is a re-operation for carotid stenosis performed more than one month after the initial procedure, report 35390 (Reoperation, carotid thromboendarterectomy) as an add-on code in conjunction with 35301.
  • Do not report 35301 in conjunction with 35201, 35206, or 35261 for the same vessel repair.
  • Radiological supervision and interpretation for intraoperative angiography may be reported separately if documented as a distinct and necessary service using code 75710 with modifier 59 or XE.

Associated ICD-10 Codes