Integrated Clinical, Biological, and Echocardiographic Factors Independently Associated With In-Hospital Mortality in Infective Endocarditis: A Single-Centre Cohort Study From Morocco.

Background Infective endocarditis (IE) remains associated with substantial in-hospital mortality worldwide, with a disproportionate burden in low- and middle-income countries (LMICs). Identifying clinical, biological, microbiological, and echocardiographic factors associated with adverse outcomes may help characterize patients at increased risk of death. Objectives To identify clinical, biological, microbiological, and echocardiographic factors independently associated with in-hospital mortality among patients hospitalized with IE in a North African tertiary referral centre. Methods We conducted a retrospective observational cohort study including 260 consecutive patients admitted with definite IE according to the 2023 Duke-International Society for Cardiovascular Infectious Diseases (Duke-ISCVID) criteria, between January 2020 and April 2026. Patients were classified as survivors (n = 188) or non-survivors (n = 72). Demographic characteristics, clinical presentation, biological parameters, microbiological data, and echocardiographic findings were systematically collected. Univariable and multivariable binary logistic regression analyses were performed. Multivariable analysis used backward Wald elimination. Model discrimination was assessed using the area under the receiver operating characteristic curve, and calibration was evaluated using the Hosmer-Lemeshow test. Results Among 260 patients with definite IE, 188 (72.3%) survived to hospital discharge, and 72 (27.7%) died during hospitalization. The mean age was 47 ± 16 years, with a male predominance. Rheumatic heart disease was the most frequent underlying valvular condition. In multivariable analysis, septic shock was associated with increased in-hospital mortality (adjusted odds ratio (aOR), 28.45; 95% CI, 3.42-106.80; p < 0.001), as were local cardiac complications (aOR, 3.52; 95% CI, 1.42-8.72; p = 0.007), age ≥60 years (aOR, 3.84; 95% CI, 1.48-9.96; p = 0.010), vegetation diameter >15 mm (aOR, 2.50; 95% CI, 1.00-6.20; p = 0.049), male sex (aOR, 2.68; 95% CI, 1.12-6.42; p = 0.027), haemoglobin <10 g/dL (aOR, 2.80; 95% CI, 1.10-7.22; p = 0.031), and estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m² (aOR, 2.70; 95% CI, 1.03-7.01; p = 0.042). The final model showed good discrimination, with a C-statistic of 0.84 (95% CI, 0.78-0.90), and no evidence of poor calibration according to the Hosmer-Lemeshow test (χ² = 6.42, df = 8, p = 0.60). Given the sparse distribution of septic shock among survivors (n = 2), a Firth-penalized sensitivity analysis yielded an OR of 9.80 (95% CI, 2.85-33.70), supporting the robustness of the direction of this association despite sparse-data concerns. Conclusions In this contemporary Moroccan cohort, septic shock, local cardiac complications, older age, vegetation diameter >15 mm, male sex, anaemia, and severe renal dysfunction were independently associated with in-hospital mortality. These findings may support early recognition of high-risk clinical features and multidisciplinary assessment, but should not be interpreted as a validated mortality prediction model. Prospective multicentre studies with internal and external validation are warranted to assess the generalizability of these findings.