Abstract 5151: Waveform Reflections and Arterial Stiffness in the Prediction of 15.1-Year All-Cause and Cardiovascular Mortalities: A Community-Based Study

Abstract

Background- The role of arterial wave reflection, usually assessed by the transit-time dependent augmentation index (AI) and augmented pressure (Pa), in the prediction of cardiovascular events may have been underestimated. We investigated whether the transit-time independent measurements of reflected wave magnitude predict cardiovascular outcomes independently of arterial stiffness indexed by carotid-femoral pulse wave velocity (PWV). Method- A total of 1272 participants (47.0% women) from a community-based survey were studied. Carotid pressure waveforms derived by tonometry were decomposed to generate forward wave amplitude (Pf), backward wave amplitude (Pb), and reflection index (RI, = [Pb/(Pf+Pb)]), in addition to AI, Pa, and reflected wave transit time (RWTT). Results During a median follow-up of 15.1 years, 225 deaths occurred, including 64 cardiovascular origins. In univariate Cox proportional hazards regression analysis, PWV, Pa and Pb predicted all-cause and cardiovascular mortalities in both men and women whereas AI, RWTT and RI were predictive only in men. In multi-variate Cox analysis accounting for age, height, and heart rate, Pb predicted all-cause mortality in women and cardiovascular mortality in both men and women, whereas Pa only predicted cardiovascular mortality in men but not in women. When PWV and Pb were jointly entered into the multivariate model accounting for age, sex, height, heart rate, and brachial mean blood pressure, Pb (hazard ratio 1.066, 95% confidence interval 1.023–1.110) but not PWV (1.086, 0.993–1.189), independently predicted cardiovascular mortality. Conclusion- Pb, a transit-time independent measurement of reflected wave magnitude, predicted long term cardiovascular mortality in men and women independently of PWV.