Improved carotid hemodynamics with vertebral reconstruction

Area of Science:

• Vascular Surgery
• Cerebrovascular Medicine
• Hemodynamics

Background:

• Carotid occlusive disease can lead to vertebrobasilar insufficiency.
• Limited treatment options exist for patients with non-reconstructible carotid occlusive disease.
• Vertebral artery reconstruction's impact on carotid hemodynamics is not well-established.

Purpose of the Study:

• To test the hypothesis that vertebral artery reconstruction improves carotid distribution hemodynamics during carotid occlusion.
• To evaluate the hemodynamic effects of direct and indirect vertebral reconstruction.

Main Methods:

• Twelve patients with vertebrobasilar symptoms underwent direct or indirect vertebral reconstruction.
• Procedures included proximal vertebral to common carotid reimplantations, carotid-vertebral bypasses, and carotid-subclavian/axillo-axillary bypasses.
• Hemodynamic parameters were measured during temporary ipsilateral carotid occlusion.

Main Results:

• Vertebral reconstruction significantly increased carotid back pressure (39.3 to 46.8 mmHg) and cerebral perfusion pressure (33.4 to 41.0 mmHg).
• The carotid collateral resistance to cerebral vascular resistance ratio decreased significantly (1.68 to 1.24).
• The ratio of carotid back pressure to mean systemic arterial pressure increased significantly (0.452 to 0.515).

Conclusions:

• Direct or indirect vertebral reconstruction positively impacts carotid hemodynamics during occlusion.
• These improvements are likely due to enhanced posterior-to-anterior blood flow.
• Vertebral reconstruction is a potential consideration for patients with symptomatic, non-reconstructible carotid occlusive disease.