4.2 WINDKESSEL-MODEL DERIVED RESERVOIR AND EXCESS PRESSURES PREDICT CARDIOVASCULAR EVENTS IN HIGH-RISK PATIENTS

Abstract

Background and aim: It has been shown that measures derived from arterial waveforms, mostly related to wave reflection (Augmentation Index, Amplitude of backward travelling wave Pb), independently predict cardiovascular events. The aim of this work is to investigate the predictive value of parameters related to the Windkessel model (reservoir pressure - PR and excess pressure - PE). Methods: Recently we developed an algorithm to calculate PR and PE, based on a 2-element Windkessel model, which can be applied on central wave-forms derived with a transfer function from radial tonometry. Results: We investigated 674 patients (mean age 63, 381 men, 126 dia- betics, 271 coronary artery disease). After a mean follow-up duration of 1382 days, 135 patients suffered from a cardiovascular event (death, myocardial infarction, stroke, coronary, cerebrovascular and peripheral revascularization). In univariate analysis, the areas under the reservoir and excess pressure (AR, AE) as well as their amplitudes (PR, PE) were significant predictors of cardiovascular events e Table. In multivariate Cox regression models (including among others: age, gender, mean BP, heart rate, diabetes, hypertension, smoking and coronary artery disease), PR was an independent predictor with a hazard ratio of 1.369 per 1 standard deviation (p Z 0.016). Conclusions: Parameters derived from Windkessel models (reservoir and excess pressure) are associated with cardiovascular events in a cohort of high-risk patients.