Impact of diverting general practitioner's after-hour calls to emergency medical dispatch centers in patients with acute myocardial infarction.

Objective: The aim of this study was to analyze the impact of diverting off-hour calls to Emergency Medical Dispatch Centers (EMDC) on time delays and revascularization procedures for patients with ST-segment elevation myocardial infarction (STEMI) in a French region.

Methods: A total of 3376 consecutive patients admitted for acute STEMI were included from the RICO survey (a French regional survey for acute myocardial infarction). Patients were retrospectively classified into two groups: before (2001-2004) and after EMDC (2005-2008) implementation and followed up for mortality as primary outcomes. In addition, we examined the impact of the diversion on the delay to definitive care.

Results: During the study, 1781 (53%) patients were evaluated before and 1595 (47%) after the EMDC implementation. Access to healthcare facilities was similar for the two groups. The rate of off-hour calls remained stable over time. The median delay from first medical intervention to hospital admission decreased from 75 to 60 min. The off-hour median interval from door to primary percutaneous coronary intervention dropped from 152 to 98 min. The multivariate analyses showed that EMDC implementing reduced preadmission delays even when adjusting for potential confounders. Moreover, EMDC implementing was associated with a fall in 30-day mortality by 60% in patients admitted during off hours and undergoing primary percutaneous coronary intervention (10 vs. 4%).

Conclusion: In a real world setting, improving the quality of prehospital organization was effective not only on reducing delays but also on improving access to revascularization. Our results showed the beneficial impact of EMDC implementing on management of STEMI.