PLASMA CHEMOTACTIC ACTIVITY DURING DIPYRIDAMOLE-INDUCED MYOCARDIAL-ISCHEMIA

Background: We have previously reported that transient myocardial isch emia induced during exercise or dipyridamole challenge leads to the re lease of increased amounts of hydrogen peroxide into circulating blood . It would indicate that the temporary functional changes within myoca rdial cells may constitute there a sterile inflammatory area. Therefor e we decided to evaluate the chemotactic properties of plasma in patie nts undergoing dipyridamole provocative test, as a sign of released in flammatory mediators. The ischemia occurrence was evaluated with Tc-99 m-SestaMIBI followed by single photon emission computed tomography (SP ECT). Methods: Blood samples were obtained from the peripheral vein of 42 patients (18 men and 24 women, mean age 61 years). Plasma chemotac tic activity was determined by the use of the Boyden chamber method: i mmediately before dipyridamole challenge (time 0), 7, and 30 min after drug infusion. The migration of control polymorphonuclear neutrophils towards evaluated plasma samples was estimated. Results: Chemotaxis o f control PMNs towards plasma isolated from patients without signs of myocardial ischemia 7 min after dipyridamole administration was signif icantly diminished in comparison with baseline values (p=0.003). Plasm a obtained 7 min after dipyridamole infusion from patients manifesting signs of myocardial ischemia by SPECT attracted control PMNs signific antly more intensively in comparison to plasma isolated at time 0 (p=0 .0005). Conclusions: The obtained results indicate that transient myoc ardial ischemia induced by dipyridamole challenge leads to generation of chemotactic factors detectable in peripheral blood plasma. (C) 1998 Elsevier Science Ireland Ltd.