Giant Lambl's Excrescence Presenting as a Peripheral Embolus

An embolus to the left popliteal artery in a 70-year-old man was found on histologic examination to be a giant Lambl's excrescence. These are fine filliform projections of fibrous tissue covered by a single layer of endothelial cells, found on normal heart valves. Fusion of these processes results in a giant filliform excrescence attached to the endocardium by a pedicle. This is the first report of such a structure embolizing and obstructing a large peripheral artery.