Arterial Wave Reflections and Incident Cardiovascular Events and Heart Failure

Abstract

Background Experimental and physiologic data mechanistically implicate wave reflections in the pathogenesis of left ventricular failure and cardiovascular disease, but their association with these outcomes in the general population is unclear. Objectives To assess the relationship between central pressure profiles and incident cardiovascular events. Methods Aortic pressure waveforms were derived from a generalized transfer function applied to the radial pressure waveform recorded non-invasively from 5,960 participants in the Multiethnic Study of Atherosclerosis (MESA). The central pressure waveform was separated into forward and reflected waves using a physiologic flow waveform. Reflection magnitude (RM=[reflected/forward wave amplitude] ×100), augmentation index (AIx=[second/first systolic peak] ×100) and pulse pressure amplification (PPA=[radial/aortic pulse pressure] ×100) were assessed as predictors of cardiovascular events (CVE) and congestive heart failure (CHF) during median 7.61 years of follow-up. Results After adjustment for established risk factors, aortic AIx independently predicted hard CVE (HR per 10%-increase=1.08; 95%CI=1.01-1.14; P=0.016), whereas PPA independently predicted all CVE (HR per 10%-increase=0.82; 95%CI=0.70-0.96; P=0.012). RM was independently predictive of all CVE (hazard ratio [HR] per 10%-increase=1.34; 95%CI=1.08-1.67; P=0.009), hard CVE (HR per 10%-increase=1.46; 95%CI=1.12-1.90; P=0.006) and strongly predictive of new-onset CHF (HR per 10%-increase=2.69; 95%CI=1.79-4.04; P<0.0001), comparing favorably to other risk factors for CHF as judged by various measures of model performance, reclassification and discrimination. In a fully-adjusted model, compared to non-hypertensive subjects with low RM, the HR for hypertensive subjects with low RM, non-hypertensive subjects with high RM and hypertensive subjects with high RM were 1.81 (95%CI=0.85-3.86), 2.16 (95%CI=1.07-5.01) and 3.98 (95%CI=1.96-8.05), respectively. Conclusions Arterial wave reflections represent a novel strong risk factor for CHF in the general population.