Hyperaggregability of platelets in thromboembolic disorders

The influence of combined treatment with propranolol and acetylsalicylic acid on platelet aggregation in coronary heart disease.

“…Increased platelet aggregation in patients with coronary artery disease has been reported several times (O'Brien, Heywood & Heady, 1966;Hampton & Gorlin, 1972;Yamazaki, Takahashi & Sano, 1975), but not in all studies (Steele, Weily, Davies & Genton, 1973;Levites & Haft, 1975). In the present study we have found no difference in spontaneous platelet aggregation and aggregation induced by adrenaline and fibrinogen in patients with coronary artery disease when compared to normal subjects.…”

Platelet aggregability measured by screen filtration pressure method in cerebrovascular diseases.

“…Such phenomenon also was found in the acute stage of thromboembolic disorders including cerebral thrombosis using the OD method. 1 In our observation, 9 a correlation was observed between the SFP value and the intensity of secondary aggregation using the OD method (P < 0.05), but the correlation coefficient was not as high, e.g., 0.534. This suggests that both methods show a platelet aggregability, but both aggregabilities represent behavior of platelets from a different standpoint.…”

“…It may suggest that an effect of thrombosis induces a hyperaggregability of platelets. In a previous report, 1 we have pointed out the importance of interaction of injured inner surface of blood vessels and platelet aggregability. In relation to this phenomenon, it is interesting that simultaneous appearance of hyperaggregability of platelets, decrease of adhesive platelet count and increase of blood coagulability occurred immediately after an exercise test on coronary sclerotic patients.…”

“…We could not find hyperaggregability of platelets in the recovery stage of cerebral thrombosis using the OD method. 1 It may show a different character of the SFP method from the OD method. As the SFP method used whole blood, it is possible that several factors in the blood may influence SFP.…”

“…1 In the above report, the platelet aggregability was measured by the optical density (OD) method used by Born' and O'Brien. 8 Though the OD method is the most popular method for detecting platelet aggregability, it was not possible to avoid destruction or injury of platelets during the centrifugation procedure required for preparation of platelet-rich plasma as a testing sample.…”