Endothelial dy~function by increasing production of endothelin-l (ET-I) and decreasing production of Nitric Oxide (NO), exacerbates myocardial ischemia in patients with stable angina and acute coronary syndromes.
The aim of the present study is to measure the plasma concentration of ET-I in patie1J.ts with coronary heart disease and to determine its relation to the clinical presentation, cardiovascular risk factors, extent, severity and angiographic lesion morphology of coronary atherosclerosis.
Sixty patients are divided into two groups according to their clinical status, group I included 30 patients with stable angina and 30 patients with unstable angina as group II, together with 20 healthy volunteers as control group were included in this study.
Venous blood samples were taken to assess fasting blood sugar, serum creatinine, lipid profile and endothelin assay.
Diagnostic coronary angiography was done for all patients using digital angiography system and standardized angiographic projections.
The results of this study showed that plasma ET-I levels were significantly elevated in patients with stable angina and unstable angina when compared with healthy control subjects. Mean plasma ET-l concentration in patients with stable angina was significantly elevated when compared with that of patients with unstable angina. There was a statistically significant difference in plasma endothelin level between patients with unstable angina who were receiving and those were not receiving heparin. There is a positive correlation between plasma ET-I level and the number of coronary vessels diseased and also with the total score of severity of CAD in patients with stable angina.
Conclusion: Endothelin-l is implicated in the pathophysiology of atherosclerotic myocardial ischemia. Heparin might be a promising tool to decrease the contribution of ET-I in the reduction of vasoconstriction during acute coronary events. Therapies that reduce ET-l concentration (like drugs which increases HDL, decreases LDL and ACE inhibitors) and inhibit its action (ET-receptor blockers) by relieving constriction may significantly lessen the hemodynamic significance of coronCllY stenosis
|
