Predictors of 30-day mortality and outcome in cases of myocardial infarction with cardiogenic shock treated by extracorporeal life support.

OBJECTIVES

The twin aims of this study were to identify the independent predictors of 30-day mortality and to analyse the outcomes of patients with cardiogenic shock (CS) associated with acute myocardial infarction (AMI) and necessitating extracorporeal life support (ECLS).

METHODS

The investigation was a single-centre, retrospective study of 77 patients who required ECLS for AMI with CS. A logistic regression analysis was performed to identify the independent variables associated with 30-day mortality.

RESULTS

Between February 2006 and November 2009, 745 patients in our establishment received ECLS. In the single-centre cohort, we retrospectively reviewed 77 patients who had required ECLS support for AMI with CS. The delay between AMI and CS ECLS was 15 ± 4 h. PCI was performed in 58 patients (75.3%) and isolated emergency CABG in 12 (15.6%). The remaining 7 patients (9.1%) did not undergo revascularization. ECLS duration averaged 9.8 ± 7.1 days. Nineteen patients were successfully weaned from ECLS (24%). Fifty-eight patients did not undergo or did not tolerate the weaning trial (76%). Forty patients died during ECLS support, 13 were implanted with a mono-ventricular (n = 9) or biventricular assist device (n = 4) and 5 were bridged to heart transplantation. Complications consisted primarily in pneumonia (51.3%) and acute renal failure requiring haemofiltration (46.1%). Pulmonary oedema occurred in 24 patients (31.6%) and major bleeding in 16 (21.33%). 30-day and in-hospital survival rates were, respectively, 38.9 and 33.8%. Multivariable analysis identified preimplantation lactate serum level, preimplantation creatinine serum level and previous cardiopulmonary resuscitation as independent predictors of 30-day mortality.

CONCLUSIONS

Prompt ECLS support is an effective strategy and provides a reasonable chance of survival in patients with AMI associated with profound CS. As shown in our results pertaining to predictive risk factors for 30-day mortality, reducing the duration of end-organ ischaemia is the keystone to management of this patient population. A major remaining challenge will consist in preventing pulmonary oedema following peripheral ECLS.