Effect of carotid endarterectomy on baroreflex sensitivity in man. Intraoperative studies.

In six patients subjected to carotid reconstructive surgery, the reflex effect on systemic pressure of unilateral carotid artery occlusion was studied before and after endarterectomy. Before endarterectomy, carotid occlusion lowered carotid sinus pressure by 45 mmHg evoking a reflex increase in systemic pressure of 12 mmHg. After endarterectomy the corresponding values were 34 mmHg and 19 mmHg. The closed loop gain of the carotid sinus reflex, calculated as the ratio of change in arterial pressure to change in carotid sinus pressure was therefore increased from 0,27 before endarterectomy to 0,56 after endarterectomy. It is concluded that carotid endarterectomy improves carotid sinus baroreflex sensitivity ant that the carotid sinus nerve should therefore be preserved whenever possible.