We describe a case of a 67-year-old woman with a history of cerebral infarction and pulmonary embolism that presented with chest pain. Subsequent evaluation resulted in a diagnosis of acute myocardial infarction and occult DVT, and imaging revealed a rare congenital absence of the infra-renal portion of the inferior vena cava, with lower extremity venous drainage diverted via an ascending lumbar vein. Associations between congenital absence of the inferior vena cava and thrombosis are discussed.