Predictive value of the APACHE II score in cardiogenic shock patients treated with a percutaneous left ventricular assist device

Johannes Mierke; Thomas Nowack; Tobias Loehn; Franziska Kluge; Frederike Poege; Uwe Speiser; Felix Woitek; Norman Mangner; Karim Ibrahim; Axel Linke; Christian Pfluecke

doi:10.1016/j.ijcha.2022.101013

Predictive value of the APACHE II score in cardiogenic shock patients treated with a percutaneous left ventricular assist device

Int J Cardiol Heart Vasc. 2022 Mar 30:40:101013. doi: 10.1016/j.ijcha.2022.101013. eCollection 2022 Jun.

Authors

Affiliations

¹ Technische Universität Dresden, Department of Internal Medicine and Cardiology, Herzzentrum Dresden, University Clinic, Dresden, Germany.
² Kreiskrankenhaus Freiberg, Klinik für Innere Medizin II, Freiberg, Germany.
³ Klinikum Chemnitz, Klinik für Innere Medizin I, Chemnitz, Germany.

Abstract

Background: The APACHE II score assesses patient prognosis in intensive care units. Different disease entities are predictable by using a specific factor called Diagnostic Category Weight (DCW). We aimed to validate the prognostic value of the APACHE II score in patients treated with a percutaneous left ventricular assist device because of refractory cardiogenic shock (CS).

Methods: From the Dresden Impella Registry, we analyzed 180 patients receiving an Impella CP®. The main outcome was the observed intrahospital mortality ( $\hat{S} (t_{h o s p})$ ), which was compared to the predicted mortality estimated by the APACHE II score.

Results: The APACHE II score, which was 33.5 ± 0.6, significantly overestimated intrahospital mortality ( $\hat{S} (t_{h o s p})$ 54.4 ± 3.7% vs. APACHE II 74.6 ± 1.6%; p < 0.001). Nevertheless, the APACHE II score showed an acceptable accuracy to predict intrahospital mortality (ROC AUC 0.70; 95% CI 0.62-0.78). Thus, we adapted the formula for calculation of predicted mortality by adjusting DCW. The total registry cohort was randomly divided into derivation group for calculation of adjusted DCW and validation group for testing. Intrahospital mortality was much more precisely predicted using the adjusted DCW compared to the conventional DCW (difference of predicted and observed mortality: -4.7 ± 2.4% vs. -23.2 ± 2.3%; p < 0.001). The new calculated DCW was -1.183 for the total cohort.

Conclusion: The APACHE II score has an acceptable accuracy for the prediction of intrahospital mortality but overestimates its total amount in CS patients. Adjustment of the DCW can lead to a much more precise prediction of prognosis.

Keywords: APACHE II score; Cardiogenic shock; Impella CP®; Percutaneous left ventricular assist device; Predicted mortality.