Short heparin thrombin clotting time, increased fibrinogen and platelet aggregates count in coronary disease: a probable hypercoagulable state.

Several indices of plasmatic and platelet coagulability (H.T.C.T., AT III, fibrinogen and Wu-Hoak test) were studied in 82 patients with acute and chronic coronary artery disease. The results were compared with those obtained in a control group. The most interesting result is the consistent shortening of H.T.C.T. as compared to the control group, particularly in patients with acute myocardial infarction. H.T.C.T. was always inversely correlated with the fibrinogen level. Those data suggest an important influence of fibrinogen levels on H.T.C.T., but this observation does not rule out the possibility that the heparin neutralizing activity (PF 4) will also influence the test. No positive correlation between H.T.C.T. and AT III could be observed. The elevated levels of AT III in acute myocardial infarction did not confirm the existence of a consumption of AT III due to chronic intravascular coagulation in these patients. The Wu-Hoak test increased only in patients with acute coronary disease, never in the other groups. In conclusion, H.T.C.T. may be assumed to be a valid test for indicating the existence of a possible hypercoagulability state.