Early complications related to acute myocardial infarction: evolution over 20 years and risk factors. The ECAMI study

Acute myocardial infarction remains a significant cause of mortality and complications. These complications are usually considered to be primarily associated with left anterior descending coronary artery involvement, i.e., with anterior infarct. The aim was to study the circumstances under which early complications occurred within the first few hours of an acute myocardial infarction. We analyzed data from a prospective, observational, multicenter prehospital registry covering the Greater Paris area. All patients meeting clinical and electrocardiographic criteria for ST-elevation myocardial infarction (STEMI) and having been managed by a mobile intensive care unit between 2006 and 2023 were included. The analysis focused on risk factors, STEMI characteristics, including the presence of complications (Killip class III or IV, conduction or rhythm disturbances, use of catecholamines, defibrillation or chest compressions, orotracheal intubation), treatment administered, response times, and outcomes. We investigated the evolution over time of complications and associated factors. A total of 30,021 patients were analyzed, 23,382 (78%) of whom were male and 6,550 (22%) female, with a median age of 60 (IQR 52-72) years. 5,038 (18%) of these patients experienced early complications. The incidence of early complications decreased significantly over time, from 21% in 2006 to 17% in 2023, with no significant variation based on infarct territory. Killip class III or IV and defibrillation or chest compressions were more common in anterior infarcts (9% vs 5%, respectively), while rhythm/conduction disturbances were more common in non-anterior infarcts (12% vs 10%). Age and response times were the primary factors associated with early complication incidence. Complication's onset was linked to higher mortality rates (15% vs. 2%; p < 0.0001). Over the past 15 years, the incidence of early complications related to STEMI and in-hospital mortality has significantly decreased. Early complication onset was not related to infarction location, but strongly related to age.