Klippel-Trenaunay-Weber syndrome (KTWS) is a rare, congenital disorder characterized
by the triad of varicose veins, cutaneous hemangiomas, and hypertrophy of soft tissue
and bone. We present the case of a woman with KTWS, cor pulmonale, and death due to
recurrent pulmonary embolism (PE). The risk of deep venous thrombosis and PE in patients
with KTWS is evaluated, and treatment recommendations are made with emphasis on the
role of early, aggressive management in the subset of patients with KTWS known to
have thromboembolic disease.