Micro-arteriovenous malformation causing spontaneous metacarpal pad hemorrhage in a dog.

A 5-year-old neutered male Labrador retriever dog with a 3-year history of intermittent hemorrhage from the right metacarpal pad was evaluated. A small region of hyperattenuation of the metacarpal pad was evident on computed tomographic angiography. Excisional biopsy of the location of the purported hemorrhage revealed a micro-arteriovenous malformation on histologic examination.