Central haemodynamic abnormalities and outcome in patients with unexplained dyspnoea.

Abstract

Little data are available regarding prognostic implications of invasive exercise testing in heart failure with preserved ejection fraction (HFpEF). The present study aimed to investigate whether rest and exercise central haemodynamic abnormalities are associated with adverse clinical outcomes in patients with dyspnea. Patients with exertional dyspnoea and ejection fraction ≥50% (n=764) underwent invasive exercise testing and follow-up for heart failure hospitalization or death. There were 117 patients with events over a median follow-up of 2.7 (interquartile range 0.5-4.6)years. Among patients with normal resting pulmonary artery wedge pressure (PAWP) (<15 mmHg, n=380 [50%]), increased exercise PAWP (≥25 mmHg) was present in 187 (24% of cohort) and was associated with 2.4-fold higher risk of events compared to those with normal exercise PAWP (<25 mmHg, n=193 [25%]) (hazard ratio [HR] 2.44; 95% confidence interval [CI] 1.11-5.36; p=0.03), while patients with elevated resting PAWP (≥15 mmHg, n=384 [50%]) displayed even higher risk compared to HFpEF with normal resting PAWP (HR 2.24; 95% CI 1.38-3.65; p=0.001). Similar findings were observed for rest/exercise right atrial pressure, and rest/exercise pulmonary artery pressures. Higher peak oxygen consumption was associated with decreased risk of events, and this relationship was solely explained by exercise cardiac output. In a multivariable-adjusted Cox model, each 1 standard deviation (SD) increase in exercise PAWP was associated with a 41% greater hazard of events (HR 1.41; 95% CI 1.13-1.76; p=0.002), while each 1 SD decrease in exercise cardiac output was associated with a 37% increased risk (HR 0.63; 95% CI 0.47-0.83; p=0.001). Haemodynamic abnormalities currently used for diagnosis of HFpEF are associated with increased risk for adverse events. Treatments that reduce central pressures while improving cardiac output reserve may offer greatest benefit to improve outcomes in HFpEF.