BACKGROUND: It has not been completely understood whether acute phase responses of unstable angina were from the disruption of coronary plaques or from the instability & hypersensitivity of the plaque itself. Meanwhile, plasma IL-6 can be affected by several systemic factors, so it is difficult to conclude that IL-6 level in peripheral blood always reflects that 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, 36 hours after undergoing percutaneous coronary intervention(PCI), respectively. RESULT: A statistically significant increase of all IL-6 levels in both coronary sinus blood and peripheral blood after PCI was noted. There was correlation between IL-6 levels in coronary sinus blood and peripheral blood after PTCA(correlation coefficient r=0.416, p=0.01), but the difference of the concentration of IL-6 between coronary sinus blood and peripheral blood after 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 IL-6 level in peripheral blood exactly reflect that of the coronary sinus blood, and that plaque rupture induced by PCI is the main cause of elevated plasma IL-6.
Angina, Unstable* ; Coronary Sinus* ; Female ; Humans ; Hypersensitivity ; Interleukin-6* ; Male ; Plasma ; Rupture