Dipyridamole and thrombocyte count in open-heart surgery.

The effect of dipyridamole (Persantine) on the thrombocyte count in connection with open-heart surgery and perfusion was studied in 12 patients. A control series of 38 patients undergoing open-heart surgery was available. The dose of dipyridamole, depending on the duration of the perfusion, was 40 to 80 mg. intravenously. We found that dipyridamole definitely had the effect of maintaining the thrombocyte count. At the end of perfusion, the mean thrombocyte count in the dipyridamole group was 129 +/- 20.6 x 10(9)/L. and in the control group 82 +/- 7.4 x 10(9)/L. The result was statistically almost significant (p less than 0.05). At the end of anesthesia the respective mean values were 164.9 +/- 29.7 and 110.8 +/- 8.1 x 10(9)/L. The difference was almost significant (p less than 0.05). The use of dipyridamole did not increase the postoperative hemorrhagic tendency. Our results support the earlier experimental findings that dipyridamole favors the maintenance of thrombocyte counts.