The measurements of the natriuretic peptide are useful and beneficial for risk stratification irrespective of the cause during admission time or during hospital stay course. the aim of the study is to Assessment of the role of Brain natriuretic peptide in diagnosis of acute coronary syndrome . Evaluation of the relation of Brain natriuretic peptide to the severity and occurrence of complications in acute coronary syndrome .

Ischemic heart disease (IHD) is regarded as one of the important leading causes of disability and death across the globe.

Acute coronary syndrome (ACS) applies to a variety of events reporting ischemia, ranging from stable angina without myocardial necrosis to ST -segment elevation myocardial infarction (STEMI). The need for prevention and detection of coronary vascular disease as early as possible by using newer and more cost effective tools is suggested . For risk stratification in patients with ACS, serial ECG monitoring and cardiac biomarkers measurement are needed as part of the diagnostic workup. B-type natriuretic peptide is synthesized as a high molecular weight precursor pro-brain natriuretic peptide (BNP) which is cleaved to release BNP and the amino-terminal fragment, N-terminal pro (NT-pro) BNP. Both peptides are released from the cardiac ventricles in response to the increased wall stress and hence its levels may indicate ventricular strain BNP is believed to have its role as natriuretic hormone and vasodilation. Among other effects are inhibition of the Renin Angiotensin-Aldosterone system(RAAS), and sympathetic nervous system. After an ischemic occurrence, BNP levels peak in 14 to 40 hours .

Inclusion Criteria:

• patients with acute coronary syndrome.

Exclusion Criteria:

• Patients with previous MI
• Eection fraction (EF) less than 30%
• Patients having cardiomyopathy
• Patients having renal, liver, malignant, infectious, or inflammatory diseases .

patients with acute coronary syndrome.