Prognostic value of dynamic cardiac biomarkers in patients with acquired refractory thrombocytopenic purpura: A retrospective study in Chinese population

Introduction Thrombotic thrombocytopenic purpura (TTP) is becoming a curable disease with the introduction of therapeutic plasma exchange (TPE). However, cardiovascular complications remain essential causes of mortality in patients with refractory TTP, while the association of cardiac biomarkers with the prognosis of TTP warrants further investigation. Methods Patients admitted to the First Affiliated Hospital of Soochow University for refractory TTP from 2013 through 2020 were included in this retrospective study. Clinical characteristics were collected from electronic health records. Biomarker levels on admission and post TPE were recorded. Logistic regression was adopted to identify risk factors for mortality. Results A total of 78 patients with refractory TTP were included in this study. Twenty-one patients died during hospitalization, with a mortality rate of 26.9%. High-sensitivity cardiac troponin T (hs-cTnT), N-terminal probrain natriuretic peptide (NT-proBNP), and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ratios (AAR) were increased in deceased patients compared with the survival group. Multivariate analysis showed that AAR after TPE was associated with overall mortality (OR: 4.45, 95% CI 1.09-18.19). The areas under the receiver operator characteristic curve (AUC) of AAR, hs-cTnT, and NT-proBNP for the association with mortality were 0.814, 0.840, and 0.829, respectively. Conclusion Higher post-TPE cardiac biomarker levels are associated with increased in-hospital mortality in patients with refractory TTP.