Abstract
AIMS: Cardiogenic shock (CS) is the leading cause of in-hospital mortality in patients suffering acute myocardial infarction (AMI). Despite advances in their management, short- and long-term mortality remain unacceptably high. We assessed short and intermediate-term outcomes for a contemporary cohort of patients with AMI-CS managed at a referral centre with a large catchment area, and sought to identify clinical factors portending a favourable prognosis. METHODS AND RESULTS: Of 1162 consecutive, unselected patients with CS we studied 316 with AMI-CS. Our primary endpoint was native heart survival (NHS) defined as survival to discharge without advanced heart failure (HF) therapies. Our secondary endpoints were adverse events, overall survival, and readmissions up to 1 year following discharge. Association of clinical data with NHS was analysed using logistic regression. Of 316 patients, 168 (53.2%) achieved NHS, 140 (44.3%) died, and 8 (2.5%) were discharged after receiving advanced HF therapies. Overall, 181 patients (57.3%) received temporary mechanical circulatory support (MCS), with 78 (24.7%) receiving intra-aortic balloon pump, 107 (33.9%) percutaneous ventricular assist device, and 62 (19.6%) veno-arterial extracorporeal membrane oxygenation. Of 176 discharged patients (55.7%), 170 (53.8%) were alive at 30 days, and 156 (49.4%) at 1-year post-discharge, while 56 (31.8%) had at least one readmission and 30 (17.0%) one HF-related readmission, by 1-year post-discharge. Patients with NHS were younger, had lower CS severity by SCAI stage, less commonly underwent intubation, or received temporary MCS, had a shorter time from CS onset to MCS deployment, and more commonly underwent coronary intervention with fewer stents deployed, compared to patients who died or underwent advanced HF therapies. Bleeding and vascular complications were less common in patients achieving NHS compared to patients who died or received advanced HF therapies. After multivariable adjustments, clinical variables associated with NHS included: younger age, lower vasoactive-inotropic score, lower serum creatinine, and lactate at shock onset, successful coronary intervention with fewer stents deployed, and absence of intubation, or use of veno-arterial extracorporeal membrane oxygenation (all P ≤ 0.05). CONCLUSION: We studied a contemporary cohort of patients with AMI-CS and high rates of temporary MCS use, and identified clinical factors associated with a higher likelihood for successful outcomes. The need for transfer to an advanced CS centre, the impact and management of adverse events, and the type and timing of temporary MCS as opposed to intensification of pharmacologic therapy, should be studied as clinical practice targets for improving patient outcomes.