P1289 Echocardiograhic prediction of pulmonary arterial capacitance in patients with heart failure with preserved ejection fraction

Background Pulmonary arterial capacitance (PAC) has emerged as one of the strongest hemodynamic predictors of adverse outcomes in a wide spectrum of cardiovascular diseases, including pulmonary hypertension in heart failure with preserved ejection fraction (HFpEF-PH). We aimed to study non-invasive surrogates for PAC using transthoracic echocardiography in this population. Methods We retrospectively evaluated consecutive patients referred to an expert tertiary care referral centre from December 2016 to November 2018. Transthoracic echocardiography (TTE) was performed within 1 year of right heart catheterization (RHC). Echo-Pac software from GE Healthcare® was used to perform echocardiographic analysis. PAC was calculated dividing right ventricular stroke volume by pulmonary arterial pulse (systolic – diastolic) pressure, measured by RHC. Results Of the 105 enrolled patients, 43 were had HFpEF-PH. Among these, 72% were female and mean age was 68.9 ± 11.2 years. Median time between TTE and RHC was 68 (IQR 34 – 191) days. Most patients were in NYHA class II (60.5%) and class III (34.9%). Fifty eight percent of the patients had history of paroxysmal or permanent atrial fibrillation. This population presented borderline parameters of right ventricle (RV) systolic dysfunction: fractional area change (FAC) 35.3 ± 9.2%, tricuspid annular plane systolic excursion (TAPSE) 18.3 ± 5.1 mm, tricuspid S’ wave 10.4 ± 2.9 and RV global longitudinal strain -15.5 ± 4.0. Regarding invasive assessment, this population presented mean pulmonary artery pressures of 38.8 ± 13.9 mmHg, pulmonary artery wedge pressure of 21.6 ± 6.4 mmHg, pulmonary vascular resistance of 3.9 ± 2.7 Wood and median PAC of 0.13 (IQR 0.09 – 0.19) ml/mmHg. The TAPSE / Pulmonary arterial systolic pressure (PASP) ratio and the Right ventricular outflow track velocity time integral (RVOT VTI) / PASP ratio were the parameters that best correlated with PAC (r = 0.69, p = 0.002 for both parameters) (table 1). These parameters were obtainable in the majority of patients (31/43). Blant-Altman analysis revealed good agreement between these measures and PAC with a mean difference of - 0.17 (CI -0.21 - -0.13) for RVOT VTI / PASP ratio and -0.23 (CI -0.28 - -0.18) for TAPSE /PASP ratio. Conclusion In a HFpEF – PH population, TAPSE / PASP and RVOT VTI / PASP are easily obtainable in most patients and significantly correlate with PAC. Abstract P1289 Figure.