Effect of nitroglycerin on the phenomenon of ischemic preconditioning in patients with ischemic heart disease during paired exercise tests

Aim. To assess effect of nitroglycerin on ischemic preconditioning (IP) in patients with ischemic heart disease during paired exercise tests on treadm ill. Material and methods. Twenty males (age 50,1+/-1,7 years) with class I I-III stable angina pectoris underwent paired exercise tests (tests 1 and 2 ) on treadmill at 15 min intervals. Test 1 was regarded as baseline and tes t 2 as the preconditioning one. In 72-hours paired exercise tests (tests 3 and 4, both after 0,5 mg of sublingual nitroglycerin) were repeated at same intervals in between. Results. Improvement of several parameters of ischem ia severity was observed during test 2 compared with test 1 (significant in creases of double product and number of METs, decrease of maximal ST-depres sion and shortening of ST depression recovery time). These data suggested t he presence of IP phenomenon. Parameters of tests 3 and 4 significantly dif fered from parameters of tests 1 and 2, implying higher tolerance to ischem ia after nitroglycerin. But there was no significant difference between res ults of tests 3 and 4. Conclusion. In patients with ischemic heart disease nitroglycerin caused significant improvement of tolerance to ischemi, but a bolished IP during repeated exercise tests.