Determination of barometric criteria for rupture of atherosclerotic plaques in the brachiocephalic arteries

Abstract

The sequence of determining determination of the critical value of blood pressure for the occurrence of dissection of atherosclerotic intima of the internal carotid artery according to the experimental study. Atherosclerotic lesion of the brachiocephalic arteries was modeled on a vascular silicone phantom of the carotid arteries, in which the surgical material (intact annular area of atherosclerotic intima with plaque), obtained after eversion endarterectomy in a patient with atherosclerotic lesions, was placed and fixed in the region of the mouth of the internal carotid artery. A total of 30 models were created. To determine the critical values of the pressure on the intima with the plaque, at which it ruptures, balloon catheters were used, controlling the pressure with a manometer. The results were compared with the preoperative data of ultrasound and computed tomography examinations of patients. Dissection of the intima in the area of the plaque occurred in 6 cases at a pressure of 150180 mm Hg; in 9 cases at 180200 mm Hg, in 3 cases at a pressure of more than 200 mmHg, in 12 when exposed to more than 300 mm Hg. All patients, whose intima ruptured at a pressure of less than 200 mm Hg, had a fluid component of the plaque on preoperative examination, and in 6 patients, the critical pressure on the plaque was 150 mm Hg., there was also a thinned "cover" of the plaque. In the rest of the cases, the plaques were stable without a liquid component. Dissection of the intima in these cases did not occur when the exposure value was more than 300 mm Hg. The presence of a fluid component in an atherosclerotic plaque of the carotid artery in combination with a thinned cover of the plaque indicates the extreme danger of its destruction and embolism during a hypertensive crisis. The degree of stenosis of the carotid artery was found to be a less significant risk factor for unstable plaque rupture than the presence of a fluid component.