The performance of an ECG by non-medicalized prehospital teams (firefighters, first responders, paramedic ambulances) is developing across the territory to cope with the increasing demand (SAMU calls) for a service that cannot meet it (limited Mobile Emergency and Resuscitation Unit - SMUR - teams).

Early diagnosis of acute coronary syndrome is key to appropriate management. A delay in care can quickly lead to complications ranging from rhythm disorders to cardiac arrest. Furthermore, as with reperfusion in strokes, the earlier reperfusion treatment is initiated, the greater the beneficial effect in ST-segment elevation myocardial infarction (STEMI).

Moreover, the main elements for diagnosing STEMI in the prehospital setting remain the ECG, along with the anamnesis (medical history) and clinical examination (typical pain).

This is an observational, retrospective and single-center study (SAMU 91) carried out between September 1, 2023 and December 31, 2024. The inclusion criteria for our study were adult patients who had been regulated by SAMU 91 during a primary intervention and who had ST+ ACS registered in the eMUST registry. The main objective was to study the difference in the admission times of patients admitted to the emergency intensive care unit of cardiology or coronary angiography and presenting with ST+ ACS on the ECG performed by a primary SMUR team versus a non-medical team referred by the SAMU. The secondary objectives were to study the descriptive variables between the two groups (SMUR and non-medicalized vector), the typicity of pain, the mortality rate and the morbidity rate between the two groups.

The list of patients with ST+ ACS in department 91 during the year 2023 and 2024 were extracted from the E-Must registry (Registry for the Evaluation in Emergency Medicine of Therapeutic Strategies for Myocardial Infarction of less than 24 hours treated by the SAMU/SMUR of Île-de-France) and the missing information was retrieved via the SAMUScript medical regulation software (call schedules, address of the place of intervention,...)

Inclusion Criteria:

• Adult patient
• Patient regulated by the SAMU 91 between 09/2023 and 12/2024
• Patient referred for coronary angiography for ST+ ACS
• Patient registered in the E-Must register (Registry for the Evaluation in Emergency Medicine of Therapeutic Strategies for Myocardial Infarction of less than 24 hours treated by the SAMU/SMUR of Île-de-France)

Exclusion Criteria:

• Secondary transport

All patients regulated by the SAMU 91 in primary intervention in the Essonne department with ST+ ACS and admitted to the ICU or coronary angiography department