Influence of Vascular Risk Factors for Atherosclerotic Carotid Artery Plaque Progression

Abstract

Background and Purpose Investigations regarding arteriosclerosis of carotid arteries showed an association between increased intima-media thickness and vascular risk factors. A newly developed three-dimensional ultrasound method increases the reproducibility of plaque volume measurements because more exact volume measurements can be performed with a reduction of the disadvantages of two-dimensional measurements. In a pilot study the influence of vascular risk factors on carotid artery plaque progression was examined. Methods Volumes of atherosclerotic plaques in carotid arteries in 54 patients were measured with a three-dimensional ultrasound system during a 12-month period to determine the relationship between progression or regression of plaque volume, vascular risk factors, dose of aspirin, and flow turbulence in the plaque region. Results A progression of plaque volume occurred in 67% (36/54) of all plaques. In no plaque was a regression of plaque volume seen. The optimal adjustment of all risk factors showed a significant influence on plaque progression ( r =.31). Diastolic blood pressure was the strongest predictor of plaque progression ( P <.01), followed by diabetes ( P <.03). Turbulence in the plaque region was found in 78% of the patients in the progression group (n=36) versus 61% in the nonprogression group (n=18) but was not significant. Dose of aspirin (100 mg versus 250/300 mg) had no influence on plaque volume after 1 year. Conclusions Treatment of vascular risk factors reduces the progression of carotid artery plaque volume in three-dimensional ultrasound. The most important factor for plaque progression is a high diastolic blood pressure. Turbulence in the flow pattern and the examined doses of aspirin showed no significant influence.