Distinct Determinants of Hospitalisation and In-Hospital Mortality After Acute Stroke: Insights into Stroke–Heart Syndrome (SHS-PARTICLES Study)

Background/Objectives: Stroke–heart syndrome (SHS) involves myocardial injury, cardiac dysfunction, and arrhythmias after acute stroke, playing a key role in prognosis. Most evidence comes from acute ischaemic stroke (IS), while cardiac involvement after haemorrhagic stroke (HS) is less understood. Additionally, the prognostic roles of cardiac biomarkers, neurological severity, and cardiac systolic function on early outcomes are not well defined. Methods: We retrospectively analysed 586 patients with stroke, assessing admission and peak high-sensitivity cardiac troponin I (hs-cTnI) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), left ventricular ejection fraction (LVEF), length of hospital stay (LOS), and in-hospital mortality. Univariable and multivariable regression analyses evaluated factors associated with mortality and LOS. Results: The cohort comprised 586 patients with acute cerebrovascular events, including 560 (95.6%) with acute ischaemic cerebrovascular disease (ischaemic ACVD) and 26 (4.4%) with HS. HS patients had higher hs-cTnI elevations and concentrations, whereas NT-proBNP did not differ between stroke subtypes. In univariable analyses, age, hs-cTnI, NT-proBNP, LVEF, National Institutes of Health Stroke Scale (NIHSS), and modified Rankin Scale (mRS) were associated with in-hospital mortality. In multivariable analysis, peak NT-proBNP remained independently associated with mortality even after logarithmic transformation. Older age, higher NIHSS and mRS scores, and lower LVEF were associated with longer LOS only in univariable analyses. Conclusions: Cardiac and neurological abnormalities provide complementary prognostic roles after acute stroke. HS was associated with a more pronounced myocardial injury profile, whereas peak NT-proBNP was independently associated with in-hospital mortality. These findings support integrated neurological and cardiovascular risk assessment after acute stroke.