Comparison between the effects of spironolactone and eplerenone in the treatment of heart failure

INTERVENTION: Intervention 1: Intervention group 1: These patients recieve oral spirinolactone tablet, 25 mg daily in addition to carvedilol and angiotensin converting enzyme inhibitor for 6 months. Intervention 2: Intervention group 2: These patients recieve oral eplerenone tablet produced by Daroupakhsh company, 25 mg daily in addition to carvedilol and angiotensin converting enzyme inhibitor for 6 months. CONDITION: I50.1 Systolic heart failure. ; Left ventricular failure PRIMARY OUTCOME: Global longitudinal systolic strain. Timepoint: at the beginning of the study and 6 months after starting treatment. Method of measurement: Echocardiography. Left ventricular ejection fraction. Timepoint: at the beginning of the study and 6 months after starting treatment. Method of measurement: Echocardiography. INCLUSION CRITERIA: New onset symptomatic systolic heart failure with left ventricular systolic ejection fraction less than 40%