Abstract 16196: E/e' Predicts Exercise Capacity in Participants Undergoing Exercise Stress Test

Abstract

Introduction: The ratio of early transmitral flow velocity (E) to early diastolic mitral annular velocity (e’) is a surrogate for left ventricular (LV) filling pressure. Post-stress E/e’ has been shown to predict exercise capacity, but few studies have investigated this correlation with baseline E/e’. Our aim was to evaluate the relationship between baseline E/e’ and exercise capacity during stress test. Methods: All patients undergoing exercise stress testing at University of Virginia from 1/2015 through 9/2015 with the required echo data were included in this study. E/e’ was categorized into quartiles. ANOVA was used to evaluate the relationship between quartiles of E/e’ and exercise duration or METS. Multivariate linear regression was used to adjust for the variables: age, sex, ejection fraction, systolic blood pressure, heart rate, and regional wall motion abnormalities. Results: Baseline characteristics of the 312 participants based on E/e’ quartiles are shown in Table 1; those with higher E/e’, on average, had higher baseline SBP, were older, and had a higher percentage of females. There was a significant difference in exercise duration and METS between E/e’ quartiles (Table 2A) [p < 0.001]. There was an inverse correlation between E/e’ and exercise capacity; the significance was more pronounced with increasing E/e’ (Table 2A) and was present even after adjusting for multiple covariates (Table 2B). Conclusions: Baseline E/e’ correlates with exercise capacity (both duration of exercise and total METS achieved). This suggests that elevated LV filling pressures at rest can predict exercise capacity and may be targeted in future studies to improve exercise tolerance.