Clinical Differences of Recent Myocardial Infarction Compared With Acute Myocardial Infarction　― Insights From the Tokyo CCU Network Multicenter Registry ―

BACKGROUND: Characteristics and treatment outcomes of acute myocardial infarction (AMI) patients have been studied; however, those of recent myocardial infarction (RMI) patients remain unclear. This study aimed to clarify characteristics, treatment strategy, and in-hospital outcomes of RMI patients in the Tokyo CCU network database. METHODS AND RESULTS: In total, 1,853 RMI and 12,494 AMI patients from the Tokyo CCU network database during 2013-2016 were compared. Both RMI and AMI were redefined by onset times of 2-28 days and ≤24 h, respectively. The RMI group had a higher average age (70.4±12.9 vs. 68.0±13.4 years, P<0.001), more women (27.6% vs. 23.6%, P<0.001), lower proportion of patients with chest pain as the chief complaint (75.2% vs. 83.6%, P<0.001), higher prevalence of diabetes mellitus (35.9% vs. 31.0%, P<0.001), and higher mechanical complication incidence (3.0% vs. 1.5%, P<0.001) than did the AMI group. Thirty-day mortality was comparable (5.3% vs. 5.8%, P=0.360); major causes of death were cardiogenic shock and mechanical complications in the AMI and RMI groups, respectively. Death from mechanical complications (not onset time) in the AMI group plateaued almost 1 week after hospitalization, whereas it continued to increase in the RMI group. CONCLUSIONS: Both RMI and AMI patients have distinctive clinical features, sequelae, and causes of death. Although treatment of RMI patients adhered to guidelines, it was insufficient, and death from mechanical complications continues to increase.