This research tries to the rate of arrhythmia manifested during the first (48) hours of heart infarction and define its nature as well as its relationship with heart infarction in regard to patients subjected to anti-coagulation (streptokinase) therapy and patients who were not subjected to it. Moreover, it also aims to detect the relationship between arrhythmia and the death rates of the patients during their stay in the Heart Intensive Care Unit. The study started in October 2012 and lasted twelve months, up to October 2013. The sample of study here consisted of (187) patients hospitalized in the Heart Intensive Care Unit having acute myocardial infarction. The sample included (142) males (76 % of the sample) and (45) females (24%). The research reached the following findings: A hundred and seven of the patients monitored in the study were smokers; and smoking was the most important risk factor causing myocardial infarction. Ventricular extra systole were the most common symptoms of acute myocardiac infarction arrhythmia during the first (48) hours of hospitalization reaching (79%). The second was increased auto ventricular rhythms rating (43 %). High rates of dangerous arrhythmia like (VT) and (VF) rating (9%) in patients who were not subjected to streptokinase (anti-coagulation) compared with those subjected to it (4. 5%), and (3.8) respectively. Decreased (EF) increased the possibility of life-threatening ventricular arrhythmia like (VT). Diabetes did not increase the dangers of arrhythmia monitored in this research