D28-05 A Multi-center Analysis Of The Clinical And Prognostic Value Of Pulmonary Arterial Wedge Pressure To Cardiac Output Slope And Peak Pulmonary Arterial Wedge Pressure In Patients With Dyspnea On Effort

Background

Peak pulmonary arterial wedge pressure (PAWP) ≥ 25mmHg and PAWP/cardiac output (CO) slope > 2mmHg/L/min have been suggested to describe an abnormal increase in left ventricular filling pressures during exercise and uncover heart failure with preserved ejection fraction (HFpEF). We aimed to compare the prognostic and clinical relevance of PAWP/CO slope to peak PAWP in patients with unclear dyspnea on effort without overt cardiopulmonary disease.

Methods

We analyzed the data of patients from the Pulmonary Hemodynamics during Exercise Network (PEX-NET), a large, multi-center research collaboration. All patients underwent resting and exercise right heart catheterization in the same body position and had a resting mean pulmonary arterial pressure < 25mmHg. We analyzed associations with all-cause mortality using spline curves, Kaplan-Meier and Cox-Regression analysis. Associations between pulmonary hemodynamics and clinical H2FpEF and HFpEF-ABA Scores were done using group comparisons and using a 2x2 contingency table.

Results

We included 680 patients from 14 centers (median age 58 [IQR 45-68] years, 65% women, HFpEF-ABA score 0.45 [0.23-0.66], follow-up 7.0 [4.4 - 10.9] years). The PAWP/CO slope was significantly associated with increased mortality risk, even after adjusting for age, sex, hemoglobin and resting hemodynamics (HR 1.10, 95%CI: 1.02-1.18, p = 0.019; Figure 1B. A PAWP/CO > 2mmHg/L/min was also associated with increased mortality (p = 0.032; Figure 1D). Peak PAWP, however, was not associated with mortality, neither as continuous variable (HR 1.0, 95%CI: 0.97-1.03, p = 0.870; Figure 1A) nor dichotomized at 25mmHg (HR 0.75, 95%CI: 0.43-1.30, p = 0.301; Figure 1C). The sensitivity and specificity for PAWP/CO slope > 2mmHg/L/min vs. peak PAWP ≥ 25mmHg to detect high HFpEF probability (HFpEF-ABA Score > 0.75) were 60% and 65% vs. 28% and 82%, respectively. A PAWP/CO slope > 2mmHg/L/min in the presence of peak PAWP < 25mmHg was frequent (23.4% of subjects) and was characterized by an increased HFpEF probability (HFpEF-ABA Score: 0.56 [0.36-0.77]).

Conclusion

In this multi-center study, an elevated PAWP/CO slope was significantly associated with increased mortality risk and elevated HFpEF scores in patients undergoing evaluation for unclear dyspnea on effort without established cardiopulmonary disease and overall only moderate HFpEF probability. Elevated peak PAWP was not associated with mortality and had low sensitivity to detect HFpEF clinically in these patients. Overall, the PAWP/CO slope may better reflect an abnormal response of the left ventricle during exercise as compared to a peak PAWP threshold.

This abstract is funded by: None; The PEX-NET (Pulmonary Haemodynamics during Exercise Network) ERS Clinical Research Collaboration acknowledges the financial support provided by the European Respiratory Society (ERS) for building the Clinical Research Collaboration. The views and conclusions in this paper are solely those of the authors and do not reflect the official position of the European Respiratory Society (ERS). ERS disclaims any responsibility for the content or opinions presented in this work.