Institutional Characteristics and Prognosis of Acute Myocardial Infarction with Cardiogenic Shock in Japan ? Analysis from the JROAD/JROAD-DPC Database

Background: The high mortality of acute myocardial infarction (AMI) with cardiogenic shock (i.e., Killip class IV AMI) remains a challenge in emergency cardiovascular care. This study aimed to examine institutional factors, including the number of JCS boardcertified members, that are independently associated with the prognosis of Killip class IV AMI patients. Methods and Results: In the Japanese registry of all cardiac and vascular diseases-diagnosis procedure combination (JROADDPC) database (years 2012-2016), the 30-day mortality of Killip class IV AMI patients (n=21,823) was 42.3%. Multivariate analysis identified age, female sex, admission by ambulance, deep coma, and cardiac arrest as patient factors that were independently associated with higher 30-day mortality, and the numbers of JCS board-certified members and of intra-aortic balloon pumping (IABP) cases per year as institutional factors that were independently associated with lower mortality in Killip class IV patients, although IABP was associated with higher mortality in Killip classes I-III patients. Among hospitals with the highest quartile (≥9 JCS boardcertified members), the 30-day mortality of Killip class IV patients was 37.4%. Conclusions: A higher numbers of JCS board-certified members was associated with better survival of Killip class IV AMI patients. This finding may provide a clue to optimizing local emergency medical services for better management of AMI patients in Japan.