Background: Although emergency care of acute myocardial infarction (AMI) could theoretically be improved through improved patient delay, this notion remains to be confirmed. Additionally, the influence of large earthquakes on the emergency care of AMI cases remains to be elucidated. The Great East Japan Earthquake (March 11, 2011) has enabled us to address these issues.
Methods and results: We analyzed the data from 2008 to 2011 (n=3,937) in the Miyagi AMI Registry Study. In-hospital mortality was significantly lower in 2011 as compared with the previous 3 years (7.3% vs. 10.5%, P<0.05). This improvement was noted especially during the first 2 months after the Earthquake, associated with shorter elapsing time from onset to admission (120 vs. 240min, P<0.001) and higher performance rate of primary percutaneous coronary intervention (PCI) (86.8% vs. 76.2%, P<0.01). Importantly, after the Earthquake, patients with early admission (≤3h from onset) was significantly increased (59.1% vs. 47.0%, P<0.05) and their prognosis became better (7.9% vs. 11.4%, P=0.02), associated with a lower prevalence of heart failure on admission (6.9% vs. 16.2%, P=0.02) and higher performance rate of primary PCI (89.1% vs. 76.4%, P<0.01).
Conclusions: Emergency care of AMI improved soon after the Great East Japan Earthquake compared with ordinary times by the contribution of earlier admission from onset and higher performance rate of primary PCI. (Circ J 2014; 78: 634-643).