Predictors associated with mortality of extracorporeal life support therapy for acute heart failure: single-center experience with 679 patients

Sebastian D Sahli; Alexander Kaserer; Julia Braun; Maximilian Halbe; Yuliya Dahlem; Muriel A Spahn; Julian Rössler; Bernard Krüger; Francesco Maisano; Donat R Spahn; Markus J Wilhelm

doi:10.21037/jtd-21-1770

Predictors associated with mortality of extracorporeal life support therapy for acute heart failure: single-center experience with 679 patients

J Thorac Dis. 2022 Jun;14(6):1960-1971. doi: 10.21037/jtd-21-1770.

Authors

Affiliations

¹ Institute of Anesthesiology, University and University Hospital Zurich, Zurich, Switzerland.
² Departments of Biostatistics and Epidemiology, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland.
³ Clinic for Cardiac Surgery, University Heart Center, University and University Hospital Zurich, Zurich, Switzerland.
⁴ Medical Controlling, Medical Directorate University Hospital Zurich, Zurich, Switzerland.
⁵ University of Zurich, Zurich, Switzerland.

^# Contributed equally.

Abstract

Background: Extracorporeal life support (ECLS) therapy is increasingly used for cardiac and respiratory support postcardiotomy, refractory cardiogenic shock and cardiopulmonary resuscitation. This study aims to describe in-hospital mortality of patients requiring ECLS, identify independent predictors associated with mortality and analyze changes of mortality over time.

Methods: This retrospective study includes all adult ECLS cases at the University Hospital Zurich, a designated ECLS center in Switzerland, in the period 2007 to 2019.

Results: ECLS therapy was required in 679 patients (median age 60 years, 27.5% female). In-hospital mortality was 55.5%. Cubic spline interpolation did not detect evidence for a change in mortality over the whole period of 13 years. In-hospital mortality significantly varied between ECLS indications: 70.7% (152/215) for postcardiotomy, 67.9% (108/159) for cardiopulmonary resuscitation, 47.0% (110/234) for refractory cardiogenic shock, and 9.9% (7/71) for lung transplantation and expansive thoracic surgery (P<0.001). Logistic regression modelling showed excellent discrimination in the receiver operating characteristic (ROC) area under the curve (AUC) of 0.89 [95% confidence interval (CI): 0.87-0.92] and identified significant mortality predictors: age, simplified acute physiology score (SAPS) II, as well as new liver failure and each allogenic blood transfusion unit given per day. ECLS after cardiopulmonary resuscitation was associated with significantly higher mortality compared to ECLS for refractory cardiogenic shock.

Conclusions: In-hospital mortality of patients treated with ECLS therapy is high. Outcomes have not changed significantly in the observed period. We identified age, SAPS II, new liver failure and each allogenic blood transfusion unit given per day as independent mortality predictors. Knowledge of predictors strongly associated with in-hospital mortality may affect future decisions about ECLS indications and the respective management to use this elaborate therapy more effectively.

Keywords: Extracorporeal circulation; extracorporeal life support (ECLS)/extracorporeal membrane oxygenation (ECMO); mortality; outcome; predictors.