To quantitatively and noninvasively evaluate common carotid atherosclerosis in a series of patients, we measured the stiffness parameter p, which represents the mechanical properties of the vessel. /3 was calculated from the relationship between blood pressure and the diameter of the artery as measured by an ultrasonic, phase-locked, echotracking system. Increases in the severity grade of atherosclerosis as subsequently determined at autopsy were correlated with increased Rvalues in 60 common carotid arteries (r=.68).C ommon carotid atherosclerosis has been reported to precede cerebral atherosclerosis.1 -2 Therefore, evaluating the severity of sclerosis in the common carotid artery may prove to be a useful prognosticator for the development of cerebrovascular sclerosis in asymptomatic individuals. Early detection of this condition can help to reduce the risk of cerebrovascular accident. Atherosclerosis causes structural changes in artery walls that alter their physical properties. The stiffness parameter /3 proposed by Hayashi et al 3 is one quantitative index of the elastic properties of large arteries. /3 can be calculated from the measurements of blood pressure and arterial diameter. Although advances in ultrasound technique have made it possible to visualize common carotid arteries, their quantitative measurement has only recently been developed. Nakayama and Sato 4 have designed an ultrasonic measuring method of arterial wall movement that uses a phase-tracking system. Moreover, Yoshimura et al 5 have developed an ultrasonic Doppler flow meter with this system that allows transcutaneous measurement of the arterial diameter and its pulsatile change. We calculated f3 from the measurements of blood pressure, arterial diameter, and its pulsatile change. A few clinical studies have included measurements of /3, 67 but no previous study has compared clinical studies with pathological findings.The aim of this study was to define the relationship between fi of the common carotid artery and the severity grade of atherosclerosis on the basis of postmortem pathological analysis. These findings may serve as reference data for noninvasively diagnosing atherosclerosis.Received August 17,1993; revision accepted December 9,1993. From the Departments of Preventive Medicine (T.W.) and Internal Medicine IV (K.K., K.F., K.I., E.T., T.F., T.U., and S.Y.), The Jikei University School of Medicine, Tokyo, Japan.Correspondence to Takashi Wada, MD, Department of Preventive Medicine, The Jikei University School of Medicine, 25-8 Nishi-shinbashi 3-chome, Minato-ku, Tokyo 105, Japan.Patients with f) values greater than 13 had a pathological diagnosis of atherosclerosis in the common carotid artery. The sensitivity of this discrimination ratio was 80%, and the specificity was 80% as well. Thus, /3 shows promise as a useful diagnostic indicator for detecting asymptomatic common carotid atherosclerosis. (Arteriosder Thromb. 1994;14:479-482 MethodsHayashi et al 3 analyzed the behavior of arterial walls by assessing changes in vess...

Physical properties of an artery can be described in terms of stiffness, distensibility, and compliance. Changes in these properties can predict atherosclerosis disease, but it is necessary to identify an index that is independent of changes in blood pressure. We measured common carotid artery diameter and pulsatile change with an ultrasonic phase-locked, echo-tracking system in 7 subjects whose mean brachial blood pressure had varied 15 mm Hg or more within a month. Patients taking antihypertensive agents were excluded from the study. We measured changes in arterial diameter (n = 41) at least four times during the study period and calculated the pressure-strain elastic modulus (Ep), distensibility coefficient (DC), cross-sectional compliance (CC) and stiffness parameter (beta) from inner diameter, its pulsatile change, and blood pressure. The correlation coefficients of mean blood pressure with each index are as follows: Ep, 0.53; DC, 0.58; CC, 0.63; beta, 0.21. When mean blood pressure increased 1 mm Hg, the change in each index at 100 mm Hg was as follows: Ep, 1.48 +/- 1.30%; DC, -1.05 +/- 0.97%; CC, -0.69 +/- 0.90%; beta, 0.45 +/- 1.11%. Among the four indices that measure the properties of the arterial walls, stiffness parameter beta was the least dependent on blood pressure. Thus, it appears to have usefulness as an index of arterial wall sclerosis.

Background Abdominal obesity as a risk factor for diagnosing metabolic syndrome (MetS) is conventionally evaluated using waist circumference (WC), although WC does not necessarily reflect visceral adiposity. Objective To examine whether replacing WC with “A Body Shape Index (ABSI)”, an abdominal obesity index calculated by dividing WC by an allometric regression of weight and height, in MetS diagnosis is useful for predicting renal function decline. Subjects/Methods In total, 5438 Japanese urban residents (median age 48 years) who participated in a public health screening program for 4 consecutive years were enrolled. Systemic arterial stiffness was assessed by cardio-ankle vascular index (CAVI). The predictability of the new-onset renal function decline (eGFR < 60 mL/min/1.73 m2) by replacing high WC with high ABSI (ABSI ≥ 0.080) was examined using three sets of MetS diagnostic criteria: Japanese, IDF and NCEP-ATPIII. Results In Japanese and NCEP-ATPIII criteria, MetS diagnosed using ABSI (ABSI-MetS) was associated with significantly higher age-adjusted CAVI compared to non-MetS, whereas MetS diagnosed using WC (WC-MetS) showed no association. Kaplan–Meier analysis of the rate of new-onset renal function decline over 4 years (total 8.7%) showed remarkable higher rate in subjects with ABSI-MetS than in those without (log-rank test p < 0.001), but almost no difference between subjects with and without WC-MetS (p = 0.014–0.617). In gender-specific Cox-proportional hazards analyses including age, proteinuria, and treatments of metabolic disorders as confounders, ABSI-MetS (Japanese criteria for both sexes, IDF criteria for men) contributed independently to the new-onset renal function decline. Of these, the contribution of IDF ABSI-MetS disappeared after adjustment by high CAVI in the subsequent analysis. Conclusion In this study, replacing WC with ABSI in MetS diagnostic criteria more efficiently predicted subjects at risk of renal function decline and arterial stiffening.

Objective: The relative usefulness of arterial stiffness parameters on renal function remains controversial. This study aimed to compare the predictive ability of three arterial stiffness parameters at baseline; cardio-ankle vascular index (CAVI), heart-ankle pulse wave velocity (haPWV) and CAVI 0 , a variant of CAVI that theoretically excludes dependence on blood pressure, for renal function decline in Japanese general population.Methods: A total of 27 864 Japanese urban residents without renal impairment at baseline who participated in two to eight consecutive (mean 3.5 AE 1.7 times) annual health examinations were studied.Results: During the study period, 6.6% of participants developed renal function decline (estimated glomerular filtration rate <60 ml/min per 1.73 m 2 ), all of whom had relatively high values in all arterial stiffness parameters. In receiver-operating characteristic curve analysis, the discriminatory power for renal function decline showed a decreasing trend of CAVI to haPWV to CAVI 0 (C-statistic: 0.740 vs. 0.734 vs. 0.726). The cut-offs were CAVI 8.0, haPWV 7.23 and CAVI 0 11.6. In Cox-proportional hazards analysis for increase of each parameter above cut-off or by 1 standard deviation (SD) adjusted for two models of confounders, only CAVI always contributed significantly to renal function decline. Restricted cubic spline regression analysis suggested that CAVI most accurately reflected the risk of renal function decline. Conclusion:Increase in arterial stiffness parameters, especially CAVI, may represent a major modifiable risk factor for renal function decline in the general population. Further research is needed to examine whether CAVIlowering interventions contribute to the prevention of chronic kidney disease.