Incidence and survival rate of bystander-witnessed out-of-hospital cardiac arrest with cardiac etiology in Osaka, Japan: a population-based study according to the Utstein style

Purpose: To clarify the incidence and survival rate of bystander-witnessed out-of-hospital cardiac arrests (OHCA) with cardiac etiology in Osaka Prefecture, Japan, with a population of nearly 9 million according to the Utstein style. Subjects and Methods: 5047 consecutive OHCA cases were treated by ambulance personnel during the 12-month period starting since 1 May 1998. 974 cases were considered to be bystander-witnessed OHCA with cardiac etiology and analyzed using the Utstein style. Results: Of the 974 cases (100%), 50 cases (5.1%) survived after 1 month and 28 (2.9%) of them after I year. The Ventricular fibrillation (VF)/ventricular tachycardia (VT) group comprised 164 (16.8%) cases and there were statistically differences between the two groups as below (the VF/VT group vs. the non-VF/VT group): gender (male: 76.8 vs. 60.7%), age (61.7 +/- 14.7 vs. 68.7 +/- 17. 1), history of ischemic heart disease (IHD) (30.5 vs. 15.3%), performance rate of bystander cardiopulmonary resuscitation (CPR) (34.1 vs. 21.4%) and time interval between receipt of an emergency call and arrival at the scene (5.5+/-2.9 vs. 6.0+/-2.9 min). Conclusion: The incidence of bystander-witnessed (OHCA) with cardiac etiology and VF or VT were remarkably low compared with those reported by other studies conducted in some areas of Europe or the USA. (C) 2003 Elsevier Ireland Ltd. All rights reserved.