Aneurysm of the subclavian artery: a complication of retrograde brachial artery catheterization.

A case of an aneurysm of an anomalous right subclavian artery following retrograde catheterization of the right brachial artery is described. This complication was not recognized until the patient presented with symptoms related to a superior mediastinal mass. After appropriate studies were performed operative intervention was successful in establishing a patent subclavian artery.