title: Excretion of thromboxane A2 and prostacyclin metabolites before and after exercise testing in patients with and without signs of ischemic heart disease.
abstract: We addressed the hypothesis that platelets are not activated in association with effort-induced myocardial ischemia in stable coronary disease. Seventy-two patients undergoing a diagnostic bicycle exercise test were stratified according to the development of chest pain (yes/no, 33/39) and of exercise-induced ST-segment depression of at least 200 microV in the electrocardiogram (yes/no, 12/60). Noninvasive indexes of platelet activation and of platelet/vessel wall interaction (urinary excretion of the 2,3-dinor-metabolites of thromboxane A2 [Tx-M] and prostacyclin [PGI-M], respectively) were analyzed in samples collected in the basal state and after the test. Basal Tx-M and PGI-M did not differ in patients with (236 +/- 35 and 131 +/- 22 pg/mg creatinine, respectively) and without (185 +/- 16 and 101 +/- 13 pg/mg creatinine, respectively) chest pain, or in those with (178 +/- 45 and 162 +/- 41 pg/mg, respectively) and without (216 +/- 22 and 104 +/- 11 pg/mg, respectively) ST-segment depression during the test. Patients without chest pain or without ST-segment depression moderately increased (p less than 0.05) their urinary Tx-M (by 21% and 13%, respectively) and PGI-M (by 28% and 23%, respectively) after exercise. No significant increases were observed in those developing chest pain or ST depression during exercise. These data indicate that effort-induced myocardial ischemia is not associated with an increase in platelet activation or platelet/vessel wall interaction in patients with stable coronary disease.
authors.affiliation: Department of Clinical Physiology, University of Gothenburg, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Wennmalm
authors.forename: J
authors.initials: J
authors.lastname: Nowak
authors.forename: T
authors.initials: T
authors.lastname: Bjurö
mesh_terms: D003327:Coronary Disease / Q000175:diagnosis / Q000652:urine*; D004562:Electrocardiography; D011464:Epoprostenol / Q000652:urine*; D015444:Exercise; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015539:Platelet Activation; D013928:Thromboxane A2 / Q000652:urine*
chemical_list: D013928:Thromboxane A2; D011464:Epoprostenol