RESUMEN
AIMS: Higher left ventricular (LV) ejection fraction (EF) is related to unfavourable prognosis in patients with heart failure (HF) with preserved ejection fraction (HFpEF). The cause of this finding needs to be haemodynamically explained. Thus, we investigated this crucial issue from the perspective of LV-arterial (A) and right ventricular (RV)-pulmonary arterial (PA) coupling. METHODS AND RESULTS: Study patients were derived from our prospective cohort study of patients hospitalized due to acute decompensated HF and LVEF > 40%. We divided the 255 patients into three groups: HF with mildly reduced EF (HFmrEF), HFpEF with 50% ≤ LVEF < 60%, and HFpEF with LVEF ≥ 60%. We compared LV end-systolic elastance (Ees), effective arterial elastance (Ea), and Ees/Ea as a representative of LV-A coupling among groups and compared the ratio of tricuspid annular plane excursion to peak pulmonary arterial systolic pressure (TAPSE/PASP) as a representative of RV-PA coupling. All-cause death and readmission due to HF-free survival was worse in the group with a higher LVEF range. Ees/Ea was greater in HFpEF patients with LVEF ≥ 60% (2.12 ± 0.57) than in those with 50% ≤ LVEF < 60% (1.20 ± 0.14) and those with HFmrEF (0.82 ± 0.09) (P < 0.001). PASP was increased in the groups with higher LVEF; however, TAPSE/PASP did not differ among groups (n = 168, P = 0.17). In a multivariate Cox proportional hazard model, TAPSE/PASP but not PASP was significantly related to event-free survival independent of LVEF. CONCLUSION: HFpEF patients with higher LVEF have unfavourable prognosis and distinctive LV-A coupling: Ees/Ea is elevated up to 2.0 or more. Impaired RV-PA coupling also worsens prognosis in such patients. CLINICAL TRIAL REGISTRATION: URL: https://www.umin.ac.jp/ctr/index.htm Unique identifier: UMIN000017725.