To the Editor: Factor VII (FVII) deficiency is the most common among the autosomally recessive inherited coagulation disorders and may result in prolonged, excessive bleeding after injury or surgery [1]. FVII, a vitamin K-dependent glycoprotein, is an integral part of the extrinsic phase of the clotting cascade. After damage to the endothelium, tissue factor is exposed to plasma components and binds to circulating FVII forming the tissue factor:factor VIIa complex [2,3]. This complex activates factors IX and X leading to activation of thrombin resulting in a thrombin burst to initiate clotting. FVII plasma levels are affected by environmental factors such as vitamin K deficiency in liver disease and during anticoagulation with vitamin K antagonists. FVII deficiency is suspected when a prolonged prothrombin time cannot be attributed to acquired factors. The activated partial thromboplastin time, thrombin time and fibrinogen concentrations remain normal. There is poor correlation with FVII levels and bleeding risk. Typically bleeding is not seen with FVII levels greater than 5% [4]. Bleeding patterns are variable, but are typically mucus membrane-derived in adults [1]. Patients with congenital FVII deficiency requiring major surgery may have a greater risk of bleeding than the general population. Perioperative bleeding management for these patients is determined on a case-by-case basis, considering baseline factor levels, bleeding history, and type of surgery. Unlike other coagulation factor deficiencies, hemostasis can be maintained throughout surgery with FVII levels as low as 5-15% [1,4]. We present the perioperative cardiac surgery management of a patient with newly diagnosed FVII deficiency.A 58 year-old male with end-stage biventricular systolic dysfunction secondary to nonischemic cardiomyopathy with an estimated left ventricular ejection fraction of 27%, atrial fibrillation, and hypertension was transferred from outside of the United States to our institution for a heart transplant evaluation. Prior to transfer, the patient had been successfully maintained on warfarin long-term for atrial fibrillation without bleeding. During his transplant evaluation, he had persistently elevated INR values for 3 weeks after warfarin withdrawal despite vitamin K repletion of 25 mg over five days. A hematologic evaluation revealed normal aPTT and fibrinogen, but FVII level of 21%. A decision was made to implant a Thoratec biventricular extracorporeal ventricular assist device (VAD) despite his mild FVII deficiency. Given this patient's lack of bleeding history while being anticoagulated with warfarin, hematology recommended using fourfactor prothrombin complex concentrate (4PCC) in the event of intraoperative bleeding in lieu of surgical prophylaxis. Preprocedure INR was 1.5, he was not pretreated with blood products or factor concentrates. The patient underwent cardiopulmonary bypass (CPB) for 248 min. After CPB ended and unfractionated heparin was reversed, the patient experienced moderate bleeding with a FVII level of 2...