Severity of Presentation, Not Sex, Increases Risk of Surgery for Infective Endocarditis

Cardiac surgery for infective endocarditis (IE) is associated with substantial short- and long-term mortality, and female sex seems to be associated with even worse outcomes. The aim of our study was to analyze the impact of sex on 30-day and long-term mortality and to identify sex-related risk factors in IE patients requiring cardiac surgery.

Relevant clinical data of all consecutive 305 patients undergoing cardiac surgery for IE between 2009 and 2016 were extracted from our institutional database and retrospectively analyzed. Infective endocarditis was defined according to the recent modified Duke criteria and surgery indicated in compliance with current European Society of Cardiology guidelines. Sex-related postoperative outcomes including 30-day and 1-year mortality were recorded. Univariate and multivariable analysis was performed to identify potential sex-dependent risk factors.

In all, 229 male patients (75.1%) and 76 female patients (24.9%) underwent surgery for IE. Female patients showed significantly more mitral valve infection (52.6% versus 33.6%, p = 0.003), and Staphylococcus aureus as causative microorganisms was diagnosed in 44.7% of female patients compared with 24.5% of male patients (p = 0.001). Female sex was associated with a higher 30-day mortality (18.4% versus 8.3%, p = 0.014) and 1-year mortality (46.1% versus 27.1%, p = 0.002). Multivariable analysis revealed not female sex, but European System for Cardiac Operative Risk Evaluation II score, reexploration for bleeding, and postoperative acute kidney injury as independent risk factors for 30-day mortality and preoperative dialysis for 1-year mortality, respectively.

In this study, female sex was associated with more severe manifestations of IE and significantly higher 30-day and 1-year mortality. After multivariable analysis, not female sex, but the underlying comorbidities seem to determine clinical outcomes.