Introduction: Acute heart failure (AHF) complicates acute Myocardial infarction (AMI) as a result of complex interaction of structural, hemodynamic, neurohormonal, and genetic maladaptations. This study aims to analyse the role of left atrial volume index (LAVI) compared to other conventional parameters of systolic and diastolic left ventricular function in patients with first time STEMI, in predicting in-hospital heart failure, in-hospital mortality and development of heart failure and mortality over a follow up period of 6 months.

Material and Methods: The present study is a prospective observational study conducted in the cardiology department of Assiut University Hospitals (AUH) on 70 STEMI patients admitted to coronary care unit (CCU). LVEF, LV wall dimensions, left atrial volume index, diastolic and systolic parameters were measured within 24 hours after admission and then 6 months later. These variables were correlated with development of heart failure according to Killip classification on admission and 6 months later by NYHA classification.

Results: There was a statistically significant difference regarding development of in-hospital heart failure (Killip classification > II) with the following variables LAV, LAVI, LVESD, FS, EF, and the diastolic parameters used to evaluate diastolic function whereas in-hospital mortality was related significantly to the same variables except LAVI, E/A ratio and EF by univariate analysis.
Six months later, follow up of our patients revealed a statistically significant relation between mortality development and the following variables; LAVI, EF, E/A ratio, DT, IVRT, TDI Septal e` and E/e` by univariate analysis.
A statistically significant relation between development of heart failure symptoms according to NYHA classification and subsequent admission was observed with the previously mentioned variables except DT and IVRT by univariate analysis.
Regarding LAVI, EF, E/A ratio, TDI septal é and E/é ratio as predictors of both in-hospital heart failure and mortality, all five variables had a statistically significant relation with development of in-hospital heart failure, but only TDI septal é and E/é ratio were significantly related to in-hospital mortality. All the previously mentioned five variables were related also to development of mortality or symptoms of heart failure and readmission over six months follow up.
Using multiple regression analysis, LAVI ml/m2, E/e` ratio, EF were the most significant predictors of in-hospital heart failure with E/e` ratio being the most powerful predictor.

Conclusions: LAVI and other determinants of systolic and diastolic functions of the heart played an important role in prediction of heart failure and mortality both in the in-hospital setting and after a follow up period of 6 months.
LAVI, E/e` ratio and EF are the most significant predictors of in hospital heart failure with E/e` ratio being the most powerful predictor.
LAVI and EF were the most powerful predictors of mortality and heart failure during a follow up period of 6 months respectively.