الفهرس 
Acknowledgment
IrisinOnly 14 pages are availabe for public view
 |  | from | 149 |  |  |
| | | from | 149 | | |
Abstract
Summary
Myocardial infarction (MI) is defined pathologically as myocardial cell death caused by prolonged ischemia. It is the most common cause of death worldwide. Ischemic heart failure (HF) is one of the major complications of MI in spite of recent advances in its management.
Irisin is one of the newly discovered myokines in 2012 by Boström and his colleagues. It is mainly synthesized from muscular tissue and the cardiac muscle is considered the best source of irisin and can affect its level. There is a growing interest about the role of irisin in cardiovascular diseases. Thus, the aim of this study is to:
1-To assess the level of serum irisin in MI patients with or without HF. 2-To evaluate possible relations among irisin, cardiac markers, lipid profile and inflammatory cytokine TNF-α.
The present study was carried on 86 subjects divided into 3 groups: 33 patients with myocardial infarction, 33 patients had myocardial infarction with heart failure and 20 subjects of matched age and sex as healthy control. All patients were admitted to Coronary Care Unit (CCU) of Assiut University hospital, Assiut, Egypt during the period from October 2015 until April 2017.
All patients were subjected to:
1- Complete history
2- Complete physical examination including blood pressure, heart rate, cardiac examination, BMI, WHR.
3- Electrocardiogram (ECG).
4-Echocardiography: Left ventricular ejection fraction (LVEF).
5-Blood samples were taken and used for determination of cardiac markers (CK-MB, troponin I) serum irisin, TNF-α and lipid profile.
Results of the present study showed that BMI, WHR systolic and diastolic blood pressure were significantly elevated in MI and HF patients in comparison to control group.
Left ventricular ejection fraction was significantly lower in MI patients and HF compared to control group and markedly decreased in HF patients in comparison to MI patients.
The cardiac biomarkers (cardiac troponin-I and CK-MB) were significantly increased in both MI and HF patients compared to the control group. While blood troponin level in HF patients was significantly lower than in MI patients, serum CK-MB level was statistically insignificantly higher.
Serum irisin level was significantly lower in MI and HF patients compared to the control group with a slightly insignificant higher level in HF patients.
Significant elevation of serum TNF-α in MI and HF patients compared to the control group was noticed with slight insignificant increase in HF patients.
Both MI and HF patients were found to have significantly higher total serum cholesterol, triglycerides and LDL- cholesterol levels and a lower serum HDL-cholesterol levels in comparison to the controls.
This study showed significant negative correlation between both BMI, WHR, systolic and diastolic blood pressure with serum irisin level in MI and HF patients, while the correlation between serum irisin level and LVEF was significantly positive in both MI and HF patients.
Significant negative correlations between irisin level and cardiac biomarkers CK-MB and troponin-I were detected in MI and HF groups.
Noteworthy, there was a significant negative correlation between serum irisin level and TNF-α in MI and HF patients.
Also, significant negative correlations between irisin and atherogenic lipids (total cholesterol, LDL-C and TGs) and a significant positive correlation between serum irisin level and HDL-C were observed in both MI and HF patients.
In conclusion, irisin levels are decreased in patients with MI and HF. It is negatively correlated to CK-MB, troponin, TNF-α, TC, LDL-C and TGs and positively correlated to HDL-C in MI and HF patients. It might be a useful biomarker in diagnosis of MI and HF beside troponin and CK-MB. Irisin could have anti-inflammatory and hypolipidemic effects. Further studies are needed to clarify the possible mechanisms and the role of irisin as a promising prophylactic or therapeutic agent in different cardiovascular diseases.