Relationship between Clinical Outcomes and Cardiopulmonary Resuscitation Time in Patients with Acute Myocardial Infarction Treated by Extracorporeal Membrane Oxygenation-Assisted Primary Percutaneous Coronary Intervention

Background and Objectives: Extracorporeal membrane oxygenation (ECMO) support is increasingly used in primary percutaneous coronary intervention (PCI) during cardiopulmonary resuscitation (CPR) to treat acute myocardial infarction (AMI) patients who experienced cardiogenic shock. However, to date, there have been no studies on the relationship between clinical outcomes and CPR time in such patients with AMI treated by ECMO-assisted primary PCI. Methods: From July 2008 to March 2016, we analyzed data from 42 AMI with cardiogenic shock patients who underwent CPR and were treated by ECMO-assisted primary PCI. The primary outcome was 30-day in-hospital mortality after primary PCI. The predictors of mortality were determined using a Cox proportional hazards model. Results: Thirty-day in-hospital mortality was observed for 33 patients (78.6%). The mean CPR time was $37.0{\pm}37.3$ minutes. The best cut-off CPR time value associated with clinical outcome was calculated to be 12.5 minutes using receiver operating characteristic curve analysis. Multivariate analysis revealed that CPR time of >12.5 minutes was an independent predictor of 30-day mortality (adjusted hazard ratio, 4.71; 95% confidence interval, 1.30-17.406; p=0.018). Conclusions: Despite ECMO support, the clinical outcomes of AMI patients with a complication of cardiogenic shock remain poor. Prolonged CPR time is associated with a poor prognosis in patients with AMI treated by ECMO-assisted primary PCI.