Pulmonary artery wedge pressure and left ventricular end-diastolic pressure during exercise in patients with dyspnoea

Abstract

BackgroundPulmonary Artery Wedge Pressure (PAWP) during exercise, as a surrogate for Left Ventricular (LV) End-Diastolic Pressure (EDP), is used to diagnose heart failure with preserved ejection fraction (HFpEF). However, LVEDP is the gold-standard to assess LV filling, end-diastolic PAWP (PAWPED) is supposed to coincide with LVEDP, and mean PAWP throughout the cardiac cycle (PAWPM) better reflects the hemodynamic load imposed on the pulmonary circulation.ObjectiveTo determine precision and accuracy of PAWP estimates for LVEDP during exercise, as well as the rate of agreement between these measures.MethodsForty-six individuals underwent simultaneous right and left heart catheterization, at rest and during exercise, to confirm/exclude HFpEF. We evaluated: linear regression between LVEDP and PAWP, Bland-Altman graphs, and the rate of concordance of dichotomized LVEDP and PAWP≥or<diagnostic thresholds for HFpEF.ResultsAt peak exercise, PAWPMand LVEDP, as well as PAWPEDand LVEDP, were fairly correlated (R2>0.69, p<0.01), with minimal bias (+2 and 0 mmHg respectively) but large limits of agreement (±11 mmHg). Eighty-nine percent of individuals had concordant PAWP and LVEDP≥or <25 mmHg (Cohen's kappa=0.64). Individuals with either LVEDP or PAWPM≥25 mmHg showed a PAWPMincrease relative to cardiac output changes (PAWPM/CO slope)>2 mmHg L−1·min−1.ConclusionsDuring exercise, PAWP is accurate but not precise for the estimation of LVEDP. Despite a good rate of concordance, these two measures might occasionally disagree.