Tsuguo Igari

Intravascular Imaging Methods for Venous Disorders.

The purposes are to assess the problems associated with intravascular imaging methods such as angioscopy and intravascular ultrasound (IVUS) and to evaluate their efficacy through the results of our observations. A total of 54 limbs in 53 patients, 50 patients with chronic venous insufficiency and 3 patients with deep vein thrombosis, were diagnosed and operated on using angioscopy (Olympus OES, order made type) and IVUS (Endosonics, model 82700). The imaging catheters were inserted through a branch of the long saphenous vein and the valves and the intraluminal views were observed. By angioscopy, intraluminal views were clearly observed in 98% of all lesions. However, observation became more difficult in iliac veins compared to in femoral and in long saphenous veins (p<0.01). Venous wall and thrombus were detected more by IVUS than by angioscopy (p<0.01), but only 21 valves (24%) were visualized by IVUS among the 88 valves observed by angioscopy. The intravascular imaging method of angioscopy is more suitable for observing valves and intraluminal views compared with IVUS, whereas IVUS is more suitable for observing the cross-sectional venous wall.

The length of the aorta from the subclavian artery to the renal artery based on computed tomographic measurements in Japanese adults

To estimate the length of the aorta from the subclavian artery to the renal artery in Japanese adults, its length was measured on computed tomographic (CT) images. Data from a total of 110 patients without aortic or aortic valvular diseases (54 men, 56 women) who had undergone 7-mm-slice-interval CT examination of the entire aorta was analyzed in this study. The length of the aorta was found to be 214.1 ± 20.7 mm and showed a positive correlation with height (r = 0.664). Especially, the length of the aorta in male patients was correlated with body mass, i.e., height, weight, and body surface area. From these results, it appears that the majority of commercially available intra-aortic balloon catheters are too long for use in the Japanese population. It is concluded that a shorter, more suitable catheter should be made available for safe use in Japanese patients.

Postoperative Alteration in the Size of Dacron Vascular Prostheses Implanted in the Infrarenal Abdominal Aorta

The degree and significance of postoperative alteration in the size of Dacron grafts in the infrarenal abdominal aorta was assessed by computed tomography. We studied a total of 41 knitted Dacron fabric grafts, comprising 28 Gelseal triaxial grafts and 13 Hemashield Microvel grafts, and 29 woven Dacron fabric (Veri-Soft Woven) grafts which were used to replace the infrarenal abdominal aneurysms. These three types of Dacron fabric dilated immediately after replacement to 1.4–1.5 times the manufactured size, but did not dilate further after the surgery.

Changes in platelet aggregation during cardiopulmonary bypass: comparison of poly-2-methoxyethylacrylate and heparin as a circuit coating material.

At present, there are various biomaterials that have high biocompatibility. In particular, there are many types of coated circuits in cardiopulmonary bypass (CPB) systems. However, only a few clinical studies have investigated platelet aggregation caused by these coated circuits. In this study, a CPB system coated with poly-2-methoxyethylacrylate (X coating) was used to ascertain whether platelet aggregation could be suppressed during CPB, and a comparison was made between X coating and ordinary (covalently bonded) heparin coating. The subjects were 19 adult patients who were scheduled to undergo valve replacement or valvuloplasty. They were divided into two groups: group X (X coating) and group H (heparin coating). The platelet aggregation threshold index (PATI, grading curve) and β-thromboglobulin and plalelet factor IV levels were assessed preoperatively (control), 5 min after heparin administration, 10 and 60 min after the start of CPB, and 0 and 2 h after the end of CPB. The results indicated that platelet aggregation was reduced during CPB and that platelets were activated. The changes in platelet aggregation associated with the X coating were shown to be similar to those associated with heparin coating.

Graft-wall endoleak 18 months after successful endoluminal AAA repair

Purpose: To describe a case of graft-wall endoleak 18 months after successful endoluminal repair of an abdominal aortic aneurysm (AAA). Methods and Results: A 71-year-old man with infrarenal AAA was successfully treated with an endoluminal aortomonoiliac graft and femorofemoral crossover bypass with surgical ligation of the right external iliac artery. The stent-graft was made from 2 Gianturco Z-stents and a tapered thin-walled (0.1-mm) Dacron graft. Eighteen months after endografting, the patient complained of a pulsatile abdominal mass. Angiography and computed tomography showed graft-wall endoleak. Aneurysmectomy was performed, and the aneurysm was successfully replaced with a Y-shaped knitted Dacron graft. A hole in the graft wall was found 3 cm from the proximal edge of the stent-graft. Conclusions: This case suggests that the use of thin-walled graft material in endografts may not be sufficiently durable.

Bland white Garland syndrome with type A aortic dissection.

We report the case of a 72-year-old patient with a left main coronary artery originating from the pulmonary trunk with type A aortic dissection. He is the oldest patient among those reported in the literature, operated due to acute type A aortic dissection and has survived 4 year after the operation without surgery on the coronary artery.

Is absence of the left coronary ostium diagnostic of Bland White Garland syndrome

Is absence of the left coronary ostium diagnostic of Bland White Garland syndrome? To the Editor: I read the recent report by Dr. Igari et al.1 describing a case of Bland-White-Garland syndrome (BWGS) with type A aortic dissection with great interest. BWGS involve the anomalous origin of the left coronary artery (LCA) from the pulmonary artery (PA) and is rare congenital defect that is often lethal if not diagnosed and treated. Long-term survival is uncommon and depends upon the development of collateral vessels from the right coronary artery (RCA) or other source. The patient reported is particularly interesting because of the absence of symptoms until the age of 72 years. Although the anomaly described could be BWGS, definitive findings to this effect do not appear in the text or figures, the only description of the LCA being, “We could not find the LCA at both the true and false lumen,” and, “Selective right coronary angiogram showed that there was retrograde filling of the left coronary system from the right coronary artery.” Absence of the left coronary ostium does not necessarily indicate BWGS. The postoperative aortogram is somewhat obscure in illustrating the origin of the LCA from the PA and retrograde blood flow filling to the LCA draining to the PA. The reported effectiveness of intraoperative myocardial protection also differs somewhat from that usually expected in older patients with this syndrome. We treated BWGS in a 50-year-old patient undergoing direct LCA reimplantation. During cardiopulmonary bypass, not even high-potassium high-flow retrograde cold blood cardioplegia did achieved satisfactory cardiac standstill due to the brisk noncoronary collateral blood flow from the systemic artery. This condition has been reported in several adults.2 Dr. Igari’s patient was extremely old and asymptomatic, so the noncoronary collateral blood flow must have been considerable, but Igari et al. accomplished the procedure without any problem in cardioplegia. In my opinion, it is unlikely that retrograde cardioplegia would work under moderate hypothermia. According to their description, the lesion was possibly atresia or acquired occlusion of the main LCA, or single right coronary artery unless they clearly show the connection of the LCA to the pulmonary artery. If the case were definitively diagnosed as BWGS, I agree it is an extremely rare case worth reporting because of the patient’s advanced age. I would thus like the authors to present the diagnostic findings for this important and interesting case. Takemi Kawara, MD Department of Surgery Kurume University School of Medicine 67 Asahi-machi, Kurume 830–0011, Japan

Radial Shunting for Renal Ischemia During Reconstruction of the Renal Artery

A new method of preserving the kidney during reconstruction of renal arteries is presented. This method of continuously perfusing the kidney with normothermic, autologous blood flow from a radial artery is very simple and provides enough time to reconstruct renal arteries even for inexperienced surgeons.

Cardiopulmonary bypass system-mountable anesthetic machine

Miniaturization of the cardiopulmonary bypass (CPB) system may provide several benefits, such as decreasing the manpower, cost, and amount of homologous blood required and improving patient care. We have proposed a portable CPB system-mountable anesthetic machine. Our portable CPB system consists of a bypass circuit, a hard shell reservoir, a membrane oxygenator, and two pumps. The reservoir has three chambers, one venous and two suction chambers. These three chambers can control the negative pressure when connected with an ordinary vacuum system in the operating room. Pumps are used for perfusion and blood transfer from suction to venous chamber. We have been working to create a newly designed pump for this system. This pump consists of a polycarbonate rotor with six polyurethane vanes and acrylic acid resin housing. The housing is narrowed at both the inflow and outflow ports. This pump has characteristics of a vane pump as well as a friction pump. By using a DC brushless motor, it is possible to perfuse from 0.1 to 10 l/min, under bench testing. Preliminary animal tests of its operation produced very satisfactory results. Regarding hemolysis, the plasma free hemoglobin level was below 80mg/dl after 4h of operation using two pumps. This low-cost disposable CPB system enables it to be used for the portable CPB system-mountable anesthetic machine.

Open Heart Surgery without Homologous Blood with Particular Reference to Preoperative Collection of Autologous Blood and Ultrafiltration during Extracorporeal Circulation.

術前貯血と限外濾過法併用により同種血輸血回避を目指した90症例を対象に無輸血開心術について検討した. 無輸血率と関連があると思われる13因子と無輸血開心術達成の多変量解析による検討で, 術後出血量, 術中失血量, 体表面積が, 無輸血開心術への関連度の高い因子として選択された. 無輸血開心術が困難と予想される症例においては, 蛙跳び法による術前貯血量の増量, さらに新鮮自己血輸血により凝固因子の温存をはかり, 出血量の軽減を行うことにより無輸血率を向上させうると考えられた.