5-YEAR FOLLOW-UP OF PATIENTS AFTER THROMBOENDARTERECTOMY OF THE INTERNAL CAROTID-ARTERY - RELEVANCE OF BARORECEPTOR SENSITIVITY

Background and Purpose In patients after myocardial infarction, barore ceptor sensitivity has been identified as a factor of prognostic relev ance. This study was designed to assess the effects of an increased ba roreceptor sensitivity in patients after surgery in the area of the in ternal carotid artery with respect to blood pressure variability, ther apeutic interventions, and vascular events during a 5-year follow-up. Methods Receptor sensitivity before and immediately after carotid surg ery was measured in 84 patients. Blood pressure variability, carotid a rtery status, and echocardiographic findings were assessed before and after surgery and at the end of follow-up. Vascular events as well as changes in blood pressure therapy during the follow-up period were eva luated. Results Significant negative correlations between an increase of baroreceptor sensitivity after surgery and the range of systolic (r =-.47; P<.001) and diastolic (r=-.33; P<.01)blood pressure were found for the immediate postoperative period. For the range of systolic bloo d pressure, this relation persisted (4.3 to 7 years after surgery) at the end of the observation period (r=-.38; P<.001). An inverse relatio n to the increase in baroreceptor function was also found for the aver age annual number of therapeutic interventions during follow-up (r=-.3 8; P<.001). Furthermore, the subgroup of patients without a postoperat ive increase of receptor sensitivity was characterized by a significan tly higher risk of major vascular events (log-rank test, P<.018). Conc lusions Because an improvement of receptor sensitivity after carotid s urgery is related to a long-lasting reduction of blood pressure levels and variability, baroreceptor function may be considered an indirect indicator for the later postoperative course.