Plasma concentrations of platelet-specific proteins and serum thromboxane B2 production in response to treatment with dipyridamole. A pilot study of 27 post-myocardial infarction patients.

: In the present study 27 post-myocardial infarction patients were treated with Persantin capsules (Depot-Kapseln, sustained release form), containing 200 mg dipyridamole, b.i.d. over a period of 3 weeks. Baseline levels for plasma beta-thromboglobulin (BTG), platelet factor 4 (PF4), and serum thromboxane B2 (TXB2) were obtained on day 0 and subsequently on days 1, 3, 5, 7, 14 and 21. The baseline levels for plasma BTG and PF4 as well as for serum TXB2 significantly exceeded those for a control group consisting of healthy subjects. The plasma values for BTG and PF4 remained unchanged during the whole study period. During the first week of study the levels for serum X TXB2 were unchanged; however, on days 14 and 21 the means for TXB2 dropped significantly. There is experimental work to suggest that dipyridamole may exert an inhibitory effect on platelet thromboxane biosynthesis. The present results support this concept.