Incidence and Predictors of In-Hospital Complications after Myocardial Infraction in Contemporary Clinical Practice: Findings from the FRENCHIE Myocardial Infarction Cohort

Introduction: It is important to identify patients presenting with myocardial infarction eligible for early hospital discharge in order to avoid prolonged hospitalizations and reduce costs. Hypothesis: From a contemporary French nationwide MI cohort, we aimed to analyze incidence and correlates of in-hospital MI complications. Methods: French Cohort of Myocardial Infarction Evaluation (FRENCHIE) is a large ongoing MI registry, which collects data from all patients admitted for MI < 48h of symptom onset in 21 French centers. In-hospital complications were collected and patients who experienced complications were compared to those who did not. Results: Overall, 9692 patients presenting with MI were enrolled (5325 STEMI (55%) and 4367 NSTEMI). Among these, 2755 (28%) presented at least one complication during hospitalization. The median length of stay was 4 days [3-7]. The complications were: high degree AV block (2.4%), atrial arrhythmias (7.7%), ventricular arrhythmias (5%), reinfarction (including stent thrombosis) (0.9%), stroke (0.6%), mitral valve and chordae rupture/tear (1.4%), ventricular free wall rupture (0.1%), ventricular septal defect (0.2%), tamponade (0.2%), heart failure (Killip class >1) (15.4%) including cardiogenic shock (3.2%) and need for assistance (1.3%), LV thrombus (1.5%), acute renal failure (4.2%), major bleeding (0.7%) and in-hospital death (2.9%). Independent predictors of the absence of any complications were: younger age (OR=0.97 and 95%CI=[0.96-0.97]), absence of PAD (1.4 [1.2-1.8]), absence of AF (2 [1.6-2.5], absence of HF (2.3 [1.7-3.1]), presentation as NSTEMI (as compared to STEMI) (1.6 [1.4-1.8]), successful PCI (0.6 [0.5-0.7]), heart rate (0.98 [0.98-0.99]), systolic blood pressure (1.01 [1.00-1.01]), creatinine (0.98 [0.97-0.99]), hemoglobin (1.06 [1.03-1.10]), leucocytes (0.94 [0.93-0.96]) and CRP (0.99 [0.99-1.00]). Conclusions: In-hospital complications after MI are still frequent (more than 1/4 of patients) and driven by atrial arrhythmias and heart failure. Patients presenting with inaugural NSTEMI successfully revascularized, with no history of cardiovascular disease, and normal heart rate, systolic blood pressure and biology parameters may be targeted for early discharge.