Cardiac fibrinoid lesions produced by cross circulation or temporary A-V shunts

Localized acute cardiac lesions containing fibrinoid were produced in rabbits by carotid-jugular cross circulation or temporary arteriovenous shunts, using small amounts of heparin as anticoagulant. Excessive amounts of heparin markedly reduced the incidence of fibrinoid in the lesions, which suggests that the formation of fibrinoid was inhibited or its deposition in the heart prevented. The results of the experiments suggest that the shunting procedures not only produce mechanical damage to the heart, but also participate in the production of fibrinoid or its precursors, which is deposited in localized sites of cardiac damage.