Abstract 4146852: Impact of Left Ventricular Diastolic Function in Pulmonary Arterial Hypertension Outcomes

Introduction: The demographics of patients with pulmonary arterial hypertension (PAH) is shifting towards older age, increased comorbidity burden, and an increase in the risk of left ventricular (LV) diastolic dysfunction. The H 2 FPEF score and probability were developed to assist in heart failure with preserved ejection fraction (HFpEF) diagnosis. We evaluated the utility of the H 2 FPEF score as well as echocardiographic measures of LV diastolic function in PAH. Hypothesis: Development of left-sided heart failure in a population of patients diagnosed with PAH may affect outcomes for those treated with PAH based therapies. Methods: Participants with an inpatient admission and a prostacyclin order at the Ohio State University Medical Center between Jan 2020 and Dec. 2022 were included. Chart review was performed to obtain clinical and echocardiographic data. The H 2 FPEF score and probability were calculated at the time of the Echo. Survival analysis was performed (Outcome: PAH related-hospitalization or death). Significant predictors of outcomes were identified using Cox logistic regression analysis. Data are presented as mean ± standard deviation or mean [interquartile range]. Results: Overall, 140 participants were identified (age: 56±16 years; BMI: 30.04±8.04 kg/m 2 ; 74% female) with normal left ejection fraction (LVEF: 63±9%). The majority were on prostacyclin therapy or no therapy at the time of the echo. Median H 2 FPEF score was 3[2-4] and median H 2 FPEF probability was 88[67-95%]. High H 2 FPEF probability was driven by high systolic PA pressure (70±22 mmHg) in the continuous equation ( Fig 1A ). The H 2 FPEF score and probability did not associate with outcomes. However, E/A ratio (HR:0.49(0.26-0.92), p=0.03) and estimated RA pressure (HR:1.1(1-1.1), p=0.02) did significantly associate with outcomes individually and in a multivariable assessment with adjusting for age and BMI ( Fig 1B ). Conclusions: The continuous H 2 FPEF probability did not perform well in this inpatient PAH cohort primarily on prostacyclin therapy. Notably measures of right and left atrial function (E/A and estimated RA pressure) did significantly associate with hospitalization and mortality. Future studies in a broader cohort of PAH patients are needed to better understand how diastolic function parameters may impact outcomes.