Chronic heart failure in an internal medicine outpatient setting: a retrospective real-world observational study of 30-day readmission and all-cause mortality

Heart failure (HF) remains a major cause of hospitalization, mortality, and healthcare burden, and its long-term management increasingly relies on structured outpatient care. This retrospective single-center observational study describes the clinical characteristics, treatment patterns, and outcomes of patients with chronic HF referred to an internal medicine outpatient clinic after hospital discharge. A total of 135 consecutive patients who attended the first specialist outpatient visit and had baseline clinical data available were included and classified according to left ventricular ejection fraction as HF with reduced, mildly reduced, or preserved ejection fraction. For this study, baseline assessment and time zero were defined as the first post-discharge outpatient visit rather than hospital discharge. The primary endpoint was readmission within 30 days from outpatient baseline assessment; the secondary endpoint was all-cause mortality during follow-up. The overall 30-day readmission rate, therefore interpreted from outpatient reassessment rather than from discharge, was 9.6%, with no significant differences across ejection fraction categories. During follow-up, 32 deaths occurred (23.7%). Although mortality was numerically higher in patients with reduced ejection fraction, survival did not significantly differ among ejection fraction groups. In adjusted analyses, older age and higher NT-proBNP appeared to carry stronger prognostic information than the ejection fraction category alone. These findings should be interpreted in light of the retrospective observational design, the selected post-discharge outpatient cohort, the limited sample size, and the definition of baseline at the first outpatient visit, which may underestimate very early post-discharge readmission events.