Coronary artery "pseudothrombus" due to collateral flow artifact distal to left circumflex coronary stenosis.

Since the complexity, morbidity, and costs of coronary interventions are increased when coronary thrombus is present, identification of the cause of an angiographic filling defect is potentially important. We present a case report and review our experience with a flow artifact that mimicked thrombus ("pseudothrombus") in the setting of a severe proximal stenosis in the left circumflex coronary artery.