Evaluation of Common Carotid Hemodynamic Forces: Relations With Wall Thickening

• Published in: Hypertension (Dallas, Tex. 1979) Vol. 34; no. 2; pp. 217 - 221
• Main Authors: Carallo, Claudio, Irace, Concetta, Pujia, Arturo, De Franceschi, Maria Serena, Crescenzo, Anna, Motti, Corradino, Cortese, Claudio, Mattioli, Pier Luigi, Gnasso, Agostino
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Philadelphia, PA American Heart Association, Inc 01.08.1999; Hagerstown, MD Lippincott
• Subjects: Adult; Age Factors; Atherosclerosis (general aspects, experimental research); Biological and medical sciences; Blood and lymphatic vessels; Blood Flow Velocity; Blood Pressure - physiology; Blood Viscosity; Body Mass Index; Cardiology. Vascular system; Carotid Artery, Common - diagnostic imaging; Carotid Artery, Common - pathology; Carotid Artery, Common - physiology; Hemodynamics; Humans; Male; Medical sciences; Middle Aged; Models, Cardiovascular; Regression Analysis; Stress, Mechanical; Tunica Intima - pathology; Tunica Media - pathology; Ultrasonography, Doppler; Human; Pathophysiology; Media; Cardiovascular disease; Vascular disease; Body mass index; Carotid; Atherosclerosis; Shear stress; Intima; Hemodynamics; Vascular wall; Thickening
• ISSN: 0194-911X; 1524-4563
• DOI: 10.1161/01.HYP.34.2.217

The localization of atherosclerotic lesions is influenced by hemodynamic factors, namely, shear stress and tensive forces. The present study investigated the relationships between shear stress and circumferential wall tension and between these hemodynamic factors and the intima-media thickness (IMT) of the common carotid artery in healthy men. Fifty-eight subjects were studied. Shear stress was calculated as blood viscosityxblood velocity/internal diameter. Circumferential wall tension was calculated as blood pressurexinternal radius. Blood velocity, internal diameter, and IMT were measured by high-resolution echo-Doppler. Mean shear stress was 12.6 +/- 3.3 dynes/cm (mean +/- SD; range, 4.8 to 20.4) and was inversely related with age, blood pressure, and body mass index (BMI). Mean circumferential wall tension was 3.4 +/- 0.6x10 dynes/cm (range 2.4 to 5.6) and was directly associated with age and BMI. IMT was inversely associated with shear stress (r=0.55, P<0.0001) and directly associated with circumferential wall tension (r=0.43, P<0.0001). Shear stress and circumferential wall tension were inversely correlated (r=0.66, P<0.0001). In multiple regression analysis, shear stress and (marginally) cholesterol were independently associated with IMT, whereas circumferential wall tension, age, and BMI were not. These findings confirm that common carotid shear stress varies among healthy individuals and decreases as age, blood pressure, and BMI increase. Our findings also demonstrate that circumferential wall tension is directly associated with wall thickness, age, and BMI and that shear stress is associated with common carotid IMT independent of other hemodynamic, clinical, or biochemical factors. (Hypertension. 1999;34:217-221.)