P2.26: Assessing Characteristics of the Cardio-Ankle Vascular Index (CAVI) and its Pwv for Arterial Function — Arm-Leg Differences and Repeatability

Abstract

Background

Vasera is a machine developed to evaluate arterial stiffness by measuring pulse wave velocity (PWV) and cardio-ankle vascular index (CAVI), apparently independent of blood pressure (BP). The 4-cuff device measures right (R) and left (L) brachial and ankle BP, deriving the CAVI value and cardiac-ankle (ca)PWV. We assessed the operating characteristics of this novel technique in clinical practice.

Method

A total of 108 patients, (13 healthy controls, 76 hypertensive, 19 with type 2 diabetes) aged 18–80 years, were measured with the Vasera 1500 (Fukuda-Denshi, Tokyo, Japan) after 10 minutes rest in a temperature controlled room. Patients with known vessel disease were excluded. Repeat visits were made after about 2 weeks.

Results

Mean±SD BMI and age were 29.6±6.1kg/m² and 50.8±16.1y respectively. Within-visit R and L CAVI were 7.8±1.5, and 7.8±1.7 units, and R and L PWV 8.1±1.5 and 8.1±1.6 m/sec. The difference between brachial systolic Rand L BP, 2.5±7mmHg, correlated with both R-PWVand L-PWV (r = 0.29 for both, p = 0.009). No significant correlation was seen between brachial or ankle R and L systolic and diastolic BP differences and R/L-CAVI, nor was there significant correlation between ankle R/ L systolic and diastolic BP difference and R-PWV or L-PWV. In 24 patients, between-visit differences in CAVI (R) were 0.14 (95%CI -0.4 to 0.6, not significant, NS) and in caPWV 0.5 (-0.3 to 1) m/sec e NS.

Conclusion

Between-visit repeatability for both CAVI & caPWV was good. The correlation between difference in arm BP and caPWV suggests possible subclinical subclavian or aortic stiffness /disease.