Paradoxical embolism to the superior mesenteric artery

Paradoxical embolism occurs when venous thrombi embolize into the systemic arterial circulation by passage of clots through an intracardiac septal defect. This paper describes a case of paradoxical embolism to the superior mesenteric artery in a patient with recent myocardial infarction and pulmonary embolism. This phenomenon was first described in 1877 (Cohnheim, 1877) and many case reports have followed but most of these have been autopsy findings. We emphasize that this diagnosis should be suspected in all patients who suffer systemic arterial emboli without any evidence of left heart origin and/or in association with pulmonary emboli. One author has reviewed 19 cases since 1930, most of which were reported in the past 15 years (Johnson, 1951). This probably reflects an increased awareness of the diagnosis and more sophisticated diagnostic modalities. It also raises the possibility that paradoxical embolism may be more common than originally believed.