Predictive model of in-hospital mortality in left-sided infective endocarditis

Abstract

Introduction and objectives: Infective endocarditis (IE) is a complex disease with high in-hospital mortality. Prognostic assessment is essential to select the most appropriate therapeutic approach; however, international IE guidelines do not provide objective assessment of the individual risk in each patient. We aimed to design a predictive model of in-hospital mortality in left-sided IE combining the prognostic variables proposed by the European guidelines.

Methods: Two prospective cohorts of consecutive patients with left-sided IE were used. Cohort 1 (n=1002) was randomized in a 2:1 ratio to obtain 2 samples: an adjustment sample to derive the model (n=688), and a validation sample for internal validation (n=314). Cohort 2 (n=133) was used for external validation.

Results: The model included age, prosthetic valve IE, comorbidities, heart failure, renal failure, septic shock, Staphylococcus aureus, fungi, periannular complications, ventricular dysfunction, and vegetations as independent predictors of in-hospital mortality. The model showed good discrimination (area under the ROC curve=0.855; 95%CI, 0.825-0.885) and calibration (P value in Hosmer-Lemeshow test=0.409), which were ratified in the internal (area under the ROC curve=0.823; 95%CI, 0.774-0.873) and external validations (area under the ROC curve=0.753; 95%CI, 0.659-0.847). For the internal validation sample (observed mortality: 29.9%) the model predicted an in-hospital mortality of 30.7% (95%CI, 27.7-33.7), and for the external validation cohort (observed mortality: 27.1%) the value was 26.4% (95%CI, 22.2-30.5).

Conclusions: A predictive model of in-hospital mortality in left-sided IE based on the prognostic variables proposed by the European Society of Cardiology IE guidelines has high discriminatory ability.

Keywords: Endocarditis infecciosa; Endocarditis infecciosa izquierda; In-hospital mortality; Infective endocarditis; Left-sided infective endocarditis; Modelo predictivo; Mortalidad hospitalaria; Predictive model.