Clinical Research Papers

Corresponding Arterial Compliance and Pulse Pressure Measurements During 24-Hour Ambulatory Monitoring

Brinton TJ, Neutel JM, Walls ED, Chio S-S, Tai L-C, Franklin SS, Smith DHG, Weber MA, UCI, Orange, CA, and Pulse Metric, Inc., San Diego, CA.

Monitoring simultaneous arterial compliance (C, ml/mmHg) and blood pressure (BP) measurements during a twenty-four hour period would be quite useful in understanding BP regulation and vascular function. However, due to the co-dependent nature of the C and BP relationship, understanding the results of monitoring sessions is complicated, especially in patients with underlying cardiovascular disease. In order to evaluate this relationship, 14 patients ranging from 30 to 80 (mean± SEM, 53± 4 years) underwent 24-hour ambulatory C and BP monitoring with the DynaPulse 5000A. This new non-invasive technology provides simultaneous measurements of C and BP by analysis of the oscillometric waveform. Natural circadian BP variations provided the opportunity to evaluate C without pharmacological intervention. C measurements were derived at mean arterial (MAP) (near end-systolic) during the cardiac cycle.

Multivariate stepwise regression analysis was performed to evaluate the effect of several independent factors on C in 798 total individual measurements (TABLE). In addition, each patient demonstrated a significant linear correlation for the C vs. pulse pressure (PP) relationship during ambulatory monitoring, average r = -0.79. Results suggest that besides MAP, pulse pressure is a strong inverse determinant of C. Due to the relationship between C and PP, differences in C in patients with matched PP may be a valuable measure of possible underlying cardiovascular disease.

*Presented at the American Society of Hypertension 11th Annual Scientific Meetings, 1996 (see American Journal of Hypertension, 1996 Vol 9, No.4, Part 2, pg. 56A).