Impact of left atrial ejection fraction following myocardial infarction on prognosis

Introduction While left ventricular (LV) remodeling lead to heart failure and mortality after a myocardial infarction (MI), left atrial dilatation remain poorly described. We sought to evaluate left atrial ejection fraction (LAEF) after MI and its impact on prognosis. Method Out of 477 patients presenting a first ST-segment elevation MI with successful revascularization, LAEF was measurable in 374 patients who constituted the population study. Cardiac magnetic resonance imaging (CMR) was performed at baseline and after a 3-month follow-up. Results A reduced LAEF represented its lower quartile (LAEF  Fig. 1 ). More, we found an interaction between redLAEF and age on its effect on heart failure during follow-up (OR = 0.47, P = 0.022), with the effect of redLAEF being more prominent amongst > 65 years old patients. Overall, LAEF improved from 40.9 ± 10.3% to 42 ± 11.2% (P = 0.038) but did not differ amongst non-redLAEF patients (P = 0.77). LAEF improved over time in redLAEF patients (n = 75) who did not suffer from cardiovascular outcomes (from 27.7 ± 6.5% to 34.2 ± 13.3, P  Conclusion LAEF was a good predictor of cardiovascular outcomes in patients after an myocardial infarction, independently of LVEF and infarct size, and more specifically amongst > 65 years old patient.