A comparison of external velour and double velour Dacron grafts in the canine thoracic aorta.

Six external velour (Bionit C. R. Bard, Inc.; Billerica, MA) and 11 double velour (Microvel Meadox Medicals, Inc.; Oakland, NJ) warp-knit Dacron grafts with lengths of 6 cm and diameters of 8 mm were implanted in the canine upper descending thoracic aorta for 56 days. Differences were observed: four of 11 double velour grafts developed major perigraft hematomas, while none of the external velour grafts exhibited this complication. Healing of the external velour grafts was virtually complete (average full wall healing and endothelial-like cell coverage of 97.0%, SD 5.9%) in contrast to the seven (of 11) double velour grafts that were free of perigraft hematoma (average full wall healing and endothelial-like cell coverage of 40.9%, SD 20.9%).