Fuyuki Asami

Erythropoietin, but not asialoerythropoietin or carbamyl-erythropoietin, attenuates monocrotaline-induced pulmonary hypertension in rats.

Erythropoietin (EPO) has long been utilized for the treatment of renal anemia. The erythropoietin receptor (EPOR) is also expressed in the cardiovascular and central nervous systems in addition to an erythroid lineage, to provide an organoprotective role against several types of cellular stress. Pulmonary hypertension (PH) is a poor prognostic disease caused by primary and secondary pulmonary vascular injury. We observed the effects of EPO derivatives on monocrotaline-induced PH in rats on the supposition that EPO may protect small arteries from injury. Asialoerythropoietin (AEPO) lacks sialic acids in the termini of carbohydrate chains that results in rapid clearance from blood. Carbamyl-erythropoietin (CEPO) interacts with EPOR/βc heterodimers, but not with EPOR homodimers expressed in erythroid cells. Monocrotaline-injected rats were treated with continuous intravenous injection of 2500 ng/kg/day of EPO, AEPO, or CEPO for 21 days, and lung histology, cardiac function, and mRNA expression in the lungs were examined. Wall thickening of small arteries in the lungs and PH were improved by administration of EPO, but not by its non-hematopoietic derivatives, AEPO, or CEPO. Erythropoietin administration increased mRNA expression of the anti-apoptotic molecule, Bcl-xL, and maintained expression of the CD31 antigen. We conclude that lungs may express EPOR homoreceptors, but not heteroreceptors. Adequate serum erythropoietin levels may be essential for pulmonary protective effects.

Floating thrombus originating from an almost normal thoracic aorta

We present a case of floating thrombus originating from an almost normal thoracic aorta in a 54-year-old man who presented with acute arterial occlusion of his left leg. Transesophageal echocardiography (TEE), computed tomography, and magnetic resonance imaging showed two masses in an almost normal aorta after embolectomy for the acute arterial occlusion. Although the embolus was thrombus histologically, malignant tumors could not be ruled out. The masses did not decrease in size after 7 days of anticoagulant therapy, so they were extirpated under cardiopulmonary bypass (CPB) and TEE guidance. Frozen section examination during CPB indicated that there was no evidence of malignancy in the removed mass. TEE played an important role in the diagnosis and surgery of this condition, and it was useful when deciding on a surgical strategy. Because the treatment strategy for this disease remains controversial, further studies are needed.

Descending aorta–external iliac artery bypass for middle aortic syndrome

We encountered a surgical case of middle aortic syndrome (MAS) in a 56-year-old man who had resistant hypertension. Computed tomography showed severe stenosis of the abdominal aorta from below the superior mesenteric artery to above the inferior mesenteric artery. Although bilateral renal artery stenosis was confirmed, renal function was within normal limits. A 10-mm vascular prosthetic graft was used to perform a descending aorta to left external iliac artery bypass. His hypertension was well controlled without medication. This extra-anatomic bypass may be a simple and useful approach for treating MAS if it is not necessary to reconstruct the renal artery or visceral artery.

Major factors of homologous blood transfusion in valvular heart operation with intraoperative autologous blood predonation in cases with difficulty in preoperative predonation

Intraoperative autologous blood predonation is reported to be useful for the prevention of homologous blood transfusion in cardiac operations, especially in on-pump coronary artery bypass grafting (CABG). However, CABG is now performed more often off-pump than on-pump. We analyzed the major factors of homologous blood transfusion in 25 consecutive cases of valvular heart operation with intraoperative autologous blood predonation except those with preoperative autologous blood donation. Homologous blood was not transfused in 18 cases, but was in 7 cases only after cardiopulmonary bypass (CPB). The homologous transfusion was not correlated with body weight, CPB dilution or duration, or preoperative hematocrit level, but was found to correlate with age (r2=0.289, p=0.0413), bleeding output (r2=0.197, p=0.0485), and predonation blood volume (r2=0.436, p=0.0152). In conclusion, suitable intraoperative predonation may reduce the necessity for homologous blood transfusion in valvular heart operations.

Successful surgical removal of an intravenous leiomyoma extending to the right atrium 4 years after hysterectomy

to the right atrium 4 years after hysterectomy Chizuo Kikuchi*, Fuyuki Asami, Kazuhiko Hanzawa and Masanori Tsuchida Division of Thoracic and Cardiovascular Surgery, Niigata University Graduate School of Medicine and Dental Sciences, Niigata, Japan * Corresponding author. Division of Thoracic and Cardiovascular Surgery, Niigata University Graduate School of Medicine and Dental Sciences, 1-757 Asahimachi-dori Chuouku, Niigata City 951-8510, Japan. Tel: +81-25-2272243; e-mail: chizuo@kk.email.ne.jp (C. Kikuchi). Received 12 September 2012; received in revised form 9 October 2012; accepted 22 October 2012

A Case of Popliteal Artery Entrapment Precisely Imaged by Multi-Scan Computed Tomography

症例は16歳,男性,高校ボクシング部選手.平成17年4月より300m走で下肢に痛みが出現する間歇性跛行のため当科を紹介受診した.ABIは右1.23,左0.99で,足部の動脈拍動は触知できた.しかし,足関節を背屈すると触知できなくなり,膝窩動脈捕捉症候群を疑った.64列マルチスライスCT(MSCT)により左膝窩動脈の内側偏位と高度狭窄,および腓腹筋内側頭による膝窩動脈の圧排を認め,左膝窩動脈捕捉症候群Delaney分類II型と診断した.手術所見では,膝窩動脈自体の器質的変化は認めず,異常筋束の切断のみで動脈の圧排は解除された.術後症状は改善し,左ABIは1.11と改善,背屈しても1.22と低下しなくなった.画像診断を中心に報告する.