Risk factors of short-term, intermediate-term, and long-term cardiac events in patients hospitalized for HFmrEF

Aims: Clinical data on the prognostic determinants over varying periods within the same cohort of heart failure with mid-range or mildly reduced ejection fraction (HFmrEF) remain scarce. This study aimed to identify the short-term, intermediate-term, and long-term risk factors of adverse cardiovascular (CV) outcomes in patients hospitalized for HFmrEF.

Methods and results: This retrospective study included 1691 consecutive HFmrEF patients admitted to our hospital between January 2015 and August 2020. Baseline data including clinical characteristics, laboratory and cardiac imaging examinations were obtained. Patients completed at least 1 year clinical follow-up after discharge by telephone interview, clinical visit, or community visit. The primary endpoint was defined as a composite of CV death or rehospitalization for heart failure (CV events) at 3, 12, and 33 months after the diagnosis of HFmrEF. Mean age of the whole cohort was 69 (61-77) years and 64.8% were male. The median clinical follow-up was 33 (20-50) months. CV events were 17.5%, 28.2%, and 57.8% at 3, 12, and 33 months after discharge, respectively. Independent risk factors for CV events were uric acid >382 μmol/L, creatinine >100 μmol/L, N-terminal pro-B type natriuretic peptide (NT-proBNP) > 3368 pg/mL and haemoglobin <120 g/L for men and <110 g/L for women at 3 and 12 months. Pulmonary artery systolic pressure >35 mmHg and the ratio of early transmitral flow velocity to early mitral annular velocity >18 served as independent risk factors for CV events at 12 months. At 33 months, uric acid > 382 μmol/L, NT-proBNP >3368 pg/mL, and pulmonary artery systolic pressure >35 mmHg were the independent risk factors of CV events.

Conclusions: Higher uric acid, creatinine, NT-proBNP, and lower haemoglobin levels at baseline are valuable serum biomarkers for risk stratification of short-term and long-term CV outcomes of HFmrEF patients. Future studies are needed to verify if intensive heart failure therapy for identified high-risk HFmrEF patients based on these four serum biomarkers could improve their short-term and long-term CV outcomes or not.