Carotid circumferential wall stress homeostasis in early remodeling: Theoretical approach and clinical application

PURPOSE: To assess the influence of cardiovascular risk factors on arterial wall growth and the remodeling process. METHODS: In a theoretical part, we used a well-established relationship linking the rate of thickening of the arterial wall to the circumferential wall stress (CWS) increase. In a clinical part, we measured the intima-media thickness (IMT) in 166 subjects with increased cardiovascular risk score but no treatment for hypertension or hypercholesterolemia, no diabetes, and no cardiovascular disease. Far wall IMT and lumen diameter were measured along the right carotid artery by high-resolution ultrasonography and computerized image analysis. RESULTS: A decreasing linear relationship between IMT and CWS was deduced from the theoretical model, implying that an increase in CWS would result in an IMT increase, and that the higher the IMT-CWS slope, the higher the thickening response. Subjects with advanced age, renal insufficiency, high 10-year Framingham risk, carotid atherosclerosis, and advanced atherosclerosis at other sites had sharper IMT-CWS slope (p < 0.05), in agreement with the homeostasis of CWS hypothesis. CONCLUSIONS: The IMT increase responding to a CWS increase was greater in high-risk patients.