Arteriotomy closure devices have been widely employed to expedite ambulation in patients undergoing diagnostic coronary angiography or percutaneous angioplasty. As compared with manual compression, these devices decrease time to complete vessel closure, allow earlier ambulation, and improve overall patient comfort. When complications occur, they are often severe and include vascular occlusion, significant bleeding, or inflammatory changes. Animal models have been used to evaluate the impact of these devices. In animal studies, the initial procedure seems to incite mild to moderate vascular spasm that resolves at an undetermined time after the initial procedure. Inflammation occurs early and is most prominent in suture-based and collagen-based procedures compared with extravascular clip procedures. At late time points (after 30 to 60 days), however, no significant differences in angiographic appearance of the vessels could be determined.