Senji Hayashi

Behavior of protein S during long-term oral anticoagulant therapy.

It has recently been reported that a natural anticoagulant, protein S (PS), is depressed during oral anticoagulation. Since more detailed information is required from the clinical standpoint, we measured plasma levels of PS [both total and free (not complexed) PS antigen], C4b-binding protein (C4bp) and other vitamin K-dependent proteins (factors II, VII, IX, X and protein C) in 60 plasma samples from patients on long-term oral anticoagulant therapy with warfarin. Together with the reduction of other vitamin K-dependent plasma proteins, PS decreased during warfarin treatment, being dependent on the intensity of the therapy. A considerable variation in plasma PS levels was also observed among individuals with a similar intensity of anticoagulation. Plasma concentration of C4bp was closely correlated with total PS level, and free PS/total PS ratio was independent of thrombotest values. These findings indicate that long-term oral anticoagulant therapy results in the suppression of the synthesis of PS, and that its reduction is on the whole balanced with C4bp and vitamin K-dependent coagulation factors. It was suggested that the metabolism of C4bp might be regulated by the plasma PS level, although this hypothesis needs further exploration.

Prediction of preserved flow to the infarct area based on admission electrocardiogram in anterior wall acute myocardial infarction

To determine whether preserved flow to the infarct area could be predicted from the admission electrocardiogram and to define the effect of preserved flow on the late results after reperfusion, 20 anterior myocardial infarction patients who were successfully reperfused were studied. Patients were divided into 3 groups: (1) no-flow group (8 patients), with an occluded infarct-related artery and no easily visible collaterals; (2) intact collateral group (6 patients); and (3) subtotal obstruction group (6 patients). From the admission electrocardiogram, the sum of ST-segment elevation (sigma ST), the sum of R-wave amplitude (sigma R) in leads V1 through V6 and the ratio of these (sigma R/sigma ST) were measured. There was no significant difference in sigma R among the 3 groups. The no-flow group had significantly lower sigma R/sigma ST and higher sigma ST than the intact collateral group or subtotal obstruction group. All patients (6 of 6) with subtotal obstruction and all except 1 patient (5 of 6) with intact collateral showed sigma R/sigma ST greater than 2.5 or sigma ST less than 2.0 mV. All patients (8 of 8) with no flow showed sigma R/sigma ST less than or equal to 2.5 and all except 1 patient with no flow (7 of 8) showed sigma ST greater than or equal to 2.0 mV. The regional wall motion was assessed by the radial method at 4 weeks. The mean percentage systolic shortening in the anterior and apical regions was significantly correlated with sigma R/sigma ST (r = 0.75, p less than 0.001) and sigma ST (r = -0.65, p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)