VA-ECMO Support in Nonsurgical Patients With Refractory Cardiogenic Shock: Pre-Implant Outcome Predictors

Refractory cardiogenic shock (RCS) is associated with a high mortality. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used as acute cardiopulmonary support but selection of VA-ECMO candidates remains challenging. There are limited data on which pre-VA-ECMO variables that predict outcome. The aim of this study was to identify pre-VA-ECMO predictors of 90-day mortality. We retrospectively analyzed 76 consecutive patients (median age 52; interquartile range [IQR]: 37-60) supported with VA-ECMO due to RCS. The association between pre-implant variables and all-cause mortality at 90 days was analyzed with multivariable logistic regression. Main etiologies of RCS were acute myocardial infarction 51% and other AHF etiologies 49%. Cardiopulmonary resuscitation was performed in 54% of patients before initiation of VA-ECMO. Median duration of VA-ECMO was 5 days (IQR: 2-11). The 90-day overall mortality was 49% and in-hospital mortality was 50%; 46% died on VA-ECMO, 37% were successfully weaned, 13% were bridged to heart transplantation, and 4% to left ventricular assist device. Multivariable logistic regression analysis identified arterial lactate (odds ratio [OR] per mmol/L: 1.15; 95% confidence interval [CI]: 1.06-1.24; P = 0.001) and number of inotropes and vasopressors (OR per agent: 2.14; 95% CI: 1.26-3.63; P = 0.005) as independent predictors of 90-day mortality. In RCS patients arterial lactate level and number of inotropes and vasopressors were identified as independent pre-VA-ECMO predictors of 90-day mortality. Thus, the severity of cardiogenic shock expressed as levels of lactate and vasoactive agents just before start of VA-ECMO may be more predictive of outcome than the specific etiology of cardiogenic shock.