ELEVATION OF FACTOR-VII ACTIVITY AND MASS IN CORONARY-ARTERY DISEASE OF VARYING SEVERITY

The present study was undertaken to determine whether the extent of Factor VII elevation correlated with the severity of coronary artery disease and whether zymogen or activated Factor VII was responsible for this elevation. A group of 69 patients with coronary artery disease with old myocardial infarction was compared with 28 control subjects. The patient groups showed elevated levels of Factor VII procoagulant activity (FVII:C) and more markedly elevated Factor VII antigen (FVII:Ag) levels than the control group; therefore they had a decreased FVII:C to FVII:Ag ratio. The increased Factor VII level in the patient groups was caused by elevated Factor VII zymogen levels, and not by activated Factor VII. Since FVII:C levels strongly correlated with the titer of thrombin-antithrombin III complexes in all patients, the hypercoagulable state accompanying severe coronary atherosclerosis seems to underlie the increase of FVII and TAT in the stable phase of myocardial infarction.