Abstract 255: Half of Patients With Acute Myocardial Infarction Died Before Receiving the Advances in Coronary Intervention: The Yamagata Acute Myocardial Infarction Registry
Authors: Hirayama Atsushi , Watanabe Tetsu , Wanezaki Masahiro , Nishiyama Satoshi , Kawasaki Ryo , Narimatsu Hiroto , Hozawa Atsushi , Kubota Isao 
Published: July 2021

Background:
Recent advances in cardiac critical care have improved the outcome in patient with AMI; however, there are patients who could not receive acute medical care due to death before arrival to hospital.

Objective:
To describe the characteristics of the persons who died of AMI before arrival to hospital in regional registry for AMI in Japan.

Methods:
The Yamagata AMI registry established as a hospital-based registration of AMI (according to the MONICA criteria) in 1993 with cooperation from every hospitals in Yamagata prefecture (located in northern part of Japan, total population were 1,168,924 in 2010). Since 2009, all death certificates in Yamagata prefecture have been collected to monitor and investigate the characteristics of AMI in this area. Cases diagnosed as I-21 (stands for AMI on 10th revision of International Classification of Disease) were registered. In the current study, we used the registration data from January 2010 to November 2012. Cases from death certificate and cases died in emergency room were defined as “death outside the hospital”, and the rest cases were defined as “case arrived alive”. Multiple regression analysis was performed to describe the features of out-of-hospital death. Age, gender, onset season and year were used as independent variables in the analysis.

Result:
A total of 3663 cases were registered, and crude incident rate of AMI was 1.001 per 1000 persons. The proportion of “death outside the hospital” was 52.4% (1920 of 3663) and 36.0% (501 of 1392) in total subjects and subjects aged <75 years, respectively. In multiple logistic regression analysis, odds ratio and 95% confidence interval for “death outside the hospital” of age (10 years increased), female (vs. male), winter (vs. summer) were 1.38 (1.27-1.49), 1.38 (1.15-1.64) and 1.58 (1.24-1.96), respectively. These associations were preserved when confined to the patients aged <75 years.

Discussion:
Compared to previous report from UK in the middle of 1990’s, fatality outside hospital seemed to be unchanged (36.0% in this analysis vs. 32.7% (1151 of 3523) in subjects aged ≤75 years). Cases derived from death certificate could overestimate this rate in our analysis; however, this is after we exclude suspicious cases such as I-46 (cardiac arrest and cardiac sudden death) or I-50.9 (heart failure, unspecified) in this registration. It is also consistent to see that delay from onset to arrival to hospital was more frequently seen in women as reported previously. We furthermore found that the risk of out-of-hospital death increased in winter season, and this might be affected to the accessibility because of the amount of snow in this study area.

Conclusion:
Approximately half of the AMI patients could not reach to hospital for acute medical care. Opportunities to reduce cardiovascular mortality are still lying outside of hospital in this era and this might be of the point of intervention to improve the care.