In 5 dogs studied over a 3-month period, we evaluated the chronic effects of the combination of deep dorsal vein arterialization with implantation of an inflatable venous compression device. The device was placed around the proximal corpora cavernosa, sparing the left dorsal artery. A left-to-right, end-to-side dorsal artery-dorsal vein fistula was fashioned, and the right dorsal vein was anastomosed to the corpus cavernosum as an end-to-side venocorporeal window. From postoperative day 15, the device was activated twice a day for 3 months. Intracavernous pressure (bilateral) and left dorsal artery blood flow were monitored, and the patency of the anastomoses was evaluated by vascular clamping, arteriography, cavernosography and microscopic dissection. The device was well-tolerated, requiring no anesthesia during activation. (A sixth dog developed glanular hyperemia and priapism and was excluded from evaluation). With cuff inflation, the intracavernous pressure was significantly higher on the experimental side (range, 20 to 106 cm. H2O higher; p = 0.028), and arteriography demonstrated contrast flowing in the fistula and window in 3 of 4 dogs in which it was done. Both clamping and microscopic dissection of the specimen showed patency of the anastomoses in all 5 dogs. Histologic examination revealed maintenance of normal cavernous tissue histology.