Blood coagulation system pathophysiology in acute myocardial infarction: the influence of anticoagulant treatment on laboratory findings.

Two hundred twenty patients admitted to a Coronary Care Unit were studied by serial plasma fibrinogen chromatography--a method for quantification of HMWFCs, native fibrinogen, and other fibrinogen derivatives in plasma. Enhanced formation of fibrin (intravascular coagulation/thrombosis) is reflected by elevation of plasma HMWFC. One hundred ten patients suffering from documented acute myocardial infarction showed early, sharp elevation of plasma HMWFC (p less than 0.001 when compared to normal and cardiac control groups), a finding which persisted for 10 to 20 days after infarction. Forty-three of the patients did not receive anticoagulant therapy, and the others received either initial heparin, heparin plus warfarin, or werfarin therapy. Plasma fibrinogen chromatographic findings, days 1 to 5, did not differ between the anticoagulated and nonanticoagulated treatment groups, although there were minor differences in the data for days 6 to 10. The results demonstrate that patients with acute myocardial infarction develop a coagulopathy characterized by enhanced fibrin formation, which is influenced to only a minor degree by conventional dosage anticoagulant therapy.