Examination of the appropriate timing of reperfusion therapy for recent myocardial infarction: a Japanese single-center retrospective study

Abstract

Background: The various guidelines clearly mention the treatment strategies for in patient of acute myocardial infarction (MI) presenting more than 24 h from symptom onset (recent myocardial infarction, RMI). However, the appropriate timing of reperfusion for RMI is unclear. Methods: We retrospectively evaluated 525 consecutive MI patients who underwent percutaneous coronary intervention (PCI) in our hospital between January 2008 and December 2012. Results: Sixty RMI patients were more frequently associated with cardiac complications such as myocardial rupture (3.3% vs. 0%; p < 0.01), ventricular septal rupture (3.3% vs. 0.4%; p < 0.05), and congestive heart failure (15% vs. 2.6%; p < 0.001) than 272 consecutive ST-elevation myocardial infarction (STEMI) patients. Of the 60 RMI patients, 33 (55.0%) underwent PCI within 7 days (early-PCI group) and 27 (45.0%) underwent PCI after 7 days (late-PCI group). Left ventricular ejection fraction measured by echocardiography at second hospital day was similar between the groups. The early-PCI group was more significantly associated with cardiogenic shock and heart failure and more frequently required intra-aortic balloon pumping (24.2% vs. 3.7%; p < 0.05) than the late-PCI group. There were no significant differences in 30-day mortality, cardiac complications, and major cardiac events during long-term follow-up (12–36 months) between the groups. Conclusion: RMI patients had a higher incidence of cardiac complications than AMI patients. Clinical outcomes were similar between patients undergoing early revascularization and those undergoing late revascularization, although the former group included a higher proportion of patients with severe cardiac failure.

Keywords

• Recent myocardial infarction
• Percutaneous coronary intervention