10-Year Temporal Trends of In-Hospital Mortality and Emergency Percutaneous Coronary Intervention for Acute Myocardial Infarction

BACKGROUND: The mortality rate of acute myocardial infarction (AMI) has improved dramatically because of reperfusion therapy during the last 40 years; however, recent temporal trends for AMI have not been fully clarified in Japan. OBJECTIVES: The purpose of this study was to elucidate the temporary trend in in-hospital mortality and treatment of AMI for the last decade in the Tokyo Metropolitan area. METHODS: We enrolled 30,553 patients from the Tokyo Cardiovascular Care Unit Network Registry, diagnosed with AMI from 2007 to 2016, as part of an ongoing, multicenter, cohort study. We analyzed the temporal trends in basic characteristics, treatment, and in-hospital mortality of AMI. RESULTS: The overall emergency percutaneous coronary intervention (PCI) rate significantly increased (P < 0.001). In particular, it remarkably increased in patients older than 80 years of age (58.3% to 70.3%, P < 0.001) and patients with Killip III or IV (Killip III, 46.9% to 65.7%; Killip IV, 65.2% to 76.6%, P < 0.001 for both). The crude and age-adjusted in-hospital mortality remained low (5.2% to 8.2% and 3.4% to 5.5%, respectively) and significantly decreased during the decade (P < 0.001). The in-hospital mortality remarkably decreased in patients older than 80 years of age (17.3% to 12.7%, P < 0.001) and in those with cardiogenic shock (38.5% to 27.3%, P < 0.001). CONCLUSIONS: This large cohort study from Tokyo revealed that in-hospital mortality of AMI significantly decreased with the increase in emergency percutaneous coronary intervention rate over the decade, particularly for high-risk patients such as older patients and those with cardiogenic shock.