Left atrial stiffness in predicting poor exercise oxygen consumption and ventilatory inefficiency

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background and Introduction Cardiopulmonary exercise test (CPET) provides integrative information of cardiovascular, pulmonary, muscular, and cellular oxidative systems. Peak exercise O2 consumption (VO2) and ventilatory efficiency (VE/VCO2) are potent predictors of poor outcome in heart failure (HF). Purpose We studied to find echocardiographic parameters to predict peak VO2 and VE/VCO2. Methods We analyzed 680 patients who underwent CPET and supine bicycle stress echocardiography simultaneously. CPET was performed using semi-supine ramp bicycle exercise with encouraging R > 1.0. Results Both poor exercise tolerance (peak VO2 < 14 mL/kg/min) and ventilatory inefficiency (VE/VCO2 > 36) were associated with age, LV mass index, LV ejection fraction, baseline or exercise E/e’, TR velocity, LA strain, peak apical rotation, and LA stiffness ((E/e’)/LA strain). In multivariate analysis, only LA stiffness was highly associated in both poor exercise tolerance(p < 0.001, odds ratio 0.96, 95% CI [0.94 0.98]) and ventilatory inefficiency(p<0.001, odds ratio 1.05, 95% CI [1.02 1.08]). Conclusion LA stiffness is independently associated with poor exercise tolerance and ventilatory inefficiency.