Beyond Respiratory Support: Clinical Profiles and Factors Associated with Mortality in Heart Failure Patients Admitted to the ICU

Background: Patients with heart failure (HF) admitted to the intensive care unit (ICU) often require respiratory support, yet comparative data on different respiratory modalities in this population remain limited. The aim of our study was to analyze clinical characteristics and outcomes of HF patients in the ICU receiving various respiratory therapies, while also identifying factors associated with mortality. Methods: This retrospective observational study categorized patients (n = 692) based on their respiratory treatments into four groups: no treatment (T-NR; n = 280); oxygen therapy (T-O2; n = 220); non-invasive mechanical ventilation (T-NIMV; n = 99); and invasive mechanical ventilation (T-IMV; n = 93). The groups were compared in terms of clinical characteristics, laboratory values at ICU admission and discharge, length of stay, and outcomes. Results: The T-IMV group had significantly higher Acute Physiology and Chronic Health Evaluation II (APACHE II) and updated Charlson Comorbidity Index scores, alongside lower ejection fractions and higher rates of vasopressor/inotrope use (p < 0.05). This group also exhibited higher mortality, longer ICU stays, and more adverse laboratory profiles (elevated lactate, creatinine, N-terminal pro-B-type natriuretic peptide-NT-proBNP, bilirubin; lower albumin). Multivariable analysis confirmed that the APACHE II score, vasopressor/inotrope requirement, and lactate and NT-proBNP levels (at admission) were independently associated with mortality (p < 0.05). Conclusions: Patients requiring IMV demonstrated greater severity of illness, as reflected by higher APACHE II scores, elevated NT-proBNP and lactate levels at admission, as well s increased requirement for vasopressor/inotrope therapy. These variables were associated with mortality, suggesting that the poorer prognosis observed in the IMV group was due to their underlying disease burden.