CHANGES IN CLOT DEFORMABILITY - A POSSIBLE EXPLANATION FOR THE EPIDEMIOLOGIC ASSOCIATION BETWEEN PLASMA-FIBRINOGEN CONCENTRATION AND MYOCARDIAL-INFARCTION

This study examined the theological properties of fibrin gels formed b y adding thrombin to plasma samples from 99 subjects with fibrinogen c oncentrations ranging from 1.45 to 4.14 g/l. A highly significant (r = 0.757; P < 0.001) inverse correlation was observed between plasma fib rinogen concentration and the extent of clot deformability as estimate d from the final value of the storage modulus (G') of the fibrin gel w hen obtained by theological analysis. A similarly significant correlat ion (r = 0.844; P < 0.001) was obtained using samples from 47 subjects in which fibrin cross-linking was blocked by addition of 0.1 mM iodoa cetamide to inactivate factor XIIIa. The characteristics of the relati onship between G' and fibrinogen concentration in the plasma samples w as comparable with that observed when the fibrin gel was formed by add ing thrombin to purified fibrinogen. These results suggest that the in creased risk of myocardial infarction associated with an elevated plas ma fibrinogen concentration may, in part, be explained on the basis of a decreased deformability of the fibrin clot formed.