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Background and Objective: Coronary artery disease (CAD) is one of the major cardiovascular diseases that affect the global population. This study was performed to evaluate the electrocardiogram (ECG) changes of patients before and after coronary artery bypass graft (CABG) surgery.
Methods: This descriptive-analytical study was performed on 100 patients (71 males and 29 females) in the age range of 37 to 78 years (mean age of 57.87±8.14 years) by census method undergoing CABG surgery in Amir Al-Momenin Kordkoy Hospital, north of Iran during the second half of 2020. Data including age, sex, and results of ECG changes, including changes in heart rate and pulse rate (PR) the day before surgery, the day of hospitalization, 4 hours after surgery, 18 hours after surgery, one day, and two days after surgery was recorded in a questionnaire.
Results: The highest mean heart rate and PR were observed at 4 hours after surgery and then heart rate and PR were reduced and on the second day, heart rate and PR were lower than  the day of hospitalization (P<0.05).
Conclusion: Considering the significant changes in ECG after surgery, careful examination and monitoring of patients, especially high-risk individuals led to early detection of significant changes in patients and reduced subsequently complications in patients with appropriate and timely treatment.