CPT® Code 35642

1. Indications

The carotid-vertebral bypass graft procedure (CPT® 35642) is indicated for patients experiencing significant obstruction or disease in the vertebral artery that may lead to compromised blood flow to the brain. The following conditions may warrant this surgical intervention:

• Vertebral Artery Stenosis - A narrowing of the vertebral artery that can restrict blood flow.
• Vertebral Artery Occlusion - Complete blockage of the vertebral artery, which can lead to serious neurological complications.
• Ischemic Symptoms - Symptoms indicating reduced blood flow to the brain, such as dizziness, vertigo, or transient ischemic attacks (TIAs).
• Trauma - Injury to the vertebral artery that may necessitate bypass to restore blood flow.

2. Procedure

The carotid-vertebral bypass graft procedure involves several critical steps to ensure successful graft placement and restoration of blood flow. The following procedural steps are performed:

• Step 1: Incision and Exposure - An incision is made over the vertebral artery below the obstructed segment. This allows for direct access to the artery, which is then carefully dissected free from surrounding tissues to minimize damage and ensure a clear working area.
• Step 2: Graft Preparation - An appropriately sized tubular synthetic graft is selected based on the dimensions of the vertebral artery and the extent of the obstruction. The graft is prepared for attachment to ensure a secure fit and optimal blood flow.
• Step 3: Clamping and Incision of the Vertebral Artery - The vertebral artery is clamped to prevent blood loss during the procedure. An incision is made in the artery to facilitate the connection of the synthetic graft.
• Step 4: Graft Attachment - The synthetic graft is sutured to the vertebral artery, ensuring that the connection is secure and that there are no leaks that could compromise the graft's function.
• Step 5: Carotid Artery Access - For the carotid-vertebral bypass, an additional incision is made in the neck over the common carotid artery. The artery is exposed, and a window is created for the placement of the synthetic graft, which is then sutured to the carotid artery.
• Step 6: Subclavian Artery Access - In cases where a subclavian-vertebral bypass is performed, an incision is made below the clavicle to expose the subclavian artery. The artery is incised, and the synthetic bypass graft is sutured to it.
• Step 7: Final Checks - After the grafts are in place, vascular clamps are removed. Blood flow through the graft is assessed using Doppler ultrasound, and distal pulses are evaluated to ensure the patency of the bypass graft.

3. Post-Procedure

Post-procedure care following a carotid-vertebral bypass graft involves monitoring the patient for any signs of complications, such as bleeding or graft failure. Patients are typically observed for neurological status to ensure that blood flow to the brain has been successfully restored. Follow-up imaging may be required to assess the integrity and function of the graft. Patients may also be advised on lifestyle modifications and medications to support vascular health and prevent future complications. Recovery time can vary based on individual patient factors and the extent of the procedure performed.