The two-in-one model: a new variation of the arteriovenous malformation model in swine

We report a new variation of the well-established experimental arteriovenou s malformation (AVM) model in swine. To provide high flow through the rete mirabile (nidus, RM) and thereby to reduce the rate of spontaneous thrombos is of the AVM, we performed an end-to-end anastomosis of the left common ca rotid artery (CCA) and the external jugular vein (EJV) microsurgically in t hree micropigs. After 1 and 4 months the animals underwent angiograms of th e CCA and vertebral artery (VA). In all cases the diversion of the blood th rough the RM was patent, up to the 4 months follow-up. We observed an arter iovenous fistula (arteriovenous pseudomalformation, pAVF) between the VA an d the EJV in each case at both 1 and 4 months. This modification of the wel l-known AVM model in the micropig could be used to monitor long-term change s after embolisation, avoiding the naturally high rate of spontaneous throm bosis. This two-in-one model is thus well suited for preclinical testing of embolic materials.