The Evaluation of Helicopter Emergency Medical Services With a Physician for Acute Myocardial Infarction in Japan: A Registry-Based Study of Prognosis and Time Reduction.

OBJECTIVE: The aim of this study was to compare the prognosis and time reduction between helicopter emergency medical services (HEMS) with a physician and ground emergency medical services (GEMS) in acute myocardial infarction (AMI) cases. METHODS: This is a registry-based study of the Japan Helicopter Emergency Medical Service Registry from April 1, 2015, to March 31, 2018. RESULTS: A total of 605 cases of AMI were registered in the HEMS group and 794 cases in the GEMS group. In the cases of non-cardiopulmonary arrest (CPA), the prognosis between HEMS and GEMS did not differ significantly. Regarding the road distance, for ranges of 20 to 40 km and > 40 km, the times from the call to the angiography room were significantly shorter with HEMS than GEMS (median 91 vs. 97 minutes, P = .036 and 101 vs. 132 minutes, P = .002, respectively). In cases of CPA, HEMS had a higher rate of return of spontaneous circulation than GEMS (55.3% vs. 36.8%, P = .038), but HEMS had a lower prognosis than GEMS (22.9% vs. 38.9%, P = .036). CONCLUSION: The present study suggested that HEMS had an advantage in reducing the time to angiography in AMI cases of non-CPA. In cases of CPA, HEMS increased the return of spontaneous circulation without improving the prognosis.