Cardiac troponin and infective endocarditis prognosis: a systematic review and meta-analysis

Aims Infective endocarditis (IE) is associated with high mortality and morbidity. Cardiac troponin (Tn) elevation seems to be common in patients with IE and could be associated with a poor prognosis. The aim of this study was to synthesize the prognostic value of Tn in patients with IE. Methods and results We searched in MEDLINE, EMBASE, and the Cochrane library, including the Cochrane Central Register of Controlled Trials (CENTRAL) until February 2020. Observational studies reporting on the association between Tn and in-hospital and 1-year mortality, and IE complications were considered eligible. As each centre uses different conventional or ultra-sensitive Tn, with different normality threshold, we considered them as normal or elevated according to the criteria specified in each article. Articles were systematically selected, assessed for bias, and, when possible, meta-analysed using a random effect model. After retrieving 542 articles, 18 were included for qualitative synthesis and 9 for quantitative meta-analysis. Compared with patients with normal Tn levels, patients with Tn elevation presented higher in-hospital mortality [odds ratio (OR) 5.96, 95% confidence interval (CI) 3.46-10.26; P<0.0001], 1-year mortality (OR 2.67, 95% CI 1.42-5.02; P=0.002), and surgery rates (OR 2.34, 95% CI 1.42-3.85; P=0.0008). They also suffered more frequent complications: central nervous system events (OR 8.85, 95% CI 3.23-24.26; P<0.0001) and cardiac abscesses (OR 4.96, 95% CI 1.94-12.70; P=0.0008). Conclusion Tn elevation is associated with a poor prognosis in patients with IE. Troponin determination seems to provide additional help in the prognostic assessment of these patients.