The Level of Interleukin-6 in Coronary sinus and peripheral blood in patiens with unstable angina after coronary intervention

Abstract

Background：It has not been completely understood whether acute phase responses of unstable angina result from a disruption of coronary plaques or from an instability & hypersensitivity of the plaque itself. Plasma IL6 can be affected by several systemic factors, so it is difficult to conclude that IL-6 level in the peripheral blood always reflects the level of the coronary sinus blood. Methods：We measured the IL-6 level in coronary sinus blood and peripheral blood of 14 patients (11 men, 3 women, mean age 55±6 years, range 43 to 65 years with unstable angina before, and 4, 8, 16, 24, and 36 hours after undergoing percutaneous coronary intervention (PCI, respectively. Results：A statistically significant increase of all IL-6 levels in both coronary sinus blood and peripheral blood following PCI was noted. There was also a correlation between IL-6 levels in coronary sinus blood and peripheral blood following PCI (correlation coefficient r＝0.416, p＝0.01, although the difference of the concentration of IL-6 between coronary sinus blood and peripheral blood following PCI was increased as time passed. There was no statistically significant relationship between the number of coronary lesions treated with PCI and the amount of elevation of plasma IL-6 level. Conclusion：It is difficult to infer that the IL-6 level in peripheral blood exactly reflects the level found in the coronary sinus blood and the plaque rupture induced by PCI is the main cause of the elevated plasma IL-6.(Korean Circulation J 2001;31(8 :773-779