CPT® Code 35515

1. Indications

Bypass graft procedures, such as the subclavian-vertebral bypass graft, are indicated for patients experiencing significant vascular obstruction or disease affecting the vertebral artery. The following conditions may warrant this surgical intervention:

• Obstructive Arterial Disease - Conditions such as atherosclerosis that lead to narrowing or blockage of the vertebral artery.
• Vertebral Artery Insufficiency - Symptoms related to inadequate blood flow to the brain, which may include dizziness, vertigo, or transient ischemic attacks.
• Trauma - Injury to the vertebral artery that compromises blood flow.
• Congenital Anomalies - Structural abnormalities of the vertebral artery that may necessitate surgical intervention.

2. Procedure

The subclavian-vertebral bypass graft procedure involves several critical steps to ensure successful grafting and restoration of blood flow. The following outlines the procedural steps:

• Step 1: Incision and Exposure - An incision is made at the base of the neck, just above the clavicle, to expose the subclavian artery. The surgeon may extend this incision to the sternal notch to facilitate access to the proximal vertebral artery.
• Step 2: Muscle Dissection - The clavicle may be divided as necessary, and the anterior scalene muscle is carefully exposed and divided, ensuring the phrenic nerve is protected during this process.
• Step 3: Nerve and Artery Exposure - The vertebral nerve fibers are divided, allowing for the exposure of the proximal vertebral artery. The distal vertebral artery may be accessed through an anterolateral approach, which involves detaching the sternocleidomastoid muscle from the mastoid process to achieve a wider exposure.
• Step 4: Vein Graft Harvesting - A vein graft is harvested, typically from the saphenous vein in the leg. An incision is made over the selected section of the saphenous vein, and surrounding soft tissue is dissected away. The vein's branches are ligated and divided, and the desired section of vein is ligated proximally and distally, then removed.
• Step 5: Graft Placement - Vascular clamps are applied to the subclavian artery, and an incision is made in the artery. The harvested vein graft is then sutured to the subclavian artery and tunneled through the neck to the vertebral artery, which is also clamped and incised.
• Step 6: Final Suturing and Blood Flow Check - The other end of the vein graft is sutured to the vertebral artery. Once all connections are made, the vascular clamps are removed, and blood flow through the graft is verified using Doppler ultrasound to ensure proper circulation.

3. Post-Procedure

After the completion of the subclavian-vertebral bypass graft procedure, patients are typically monitored for any complications and to ensure that the graft is functioning correctly. Post-operative care may include pain management, monitoring for signs of infection, and ensuring that blood flow is adequate. Patients may be advised on activity restrictions and follow-up appointments to assess the success of the graft and overall recovery. Rehabilitation may be necessary to restore full function and mobility, depending on the individual’s condition and the extent of the surgery.