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An animal experiment was done using six mongrel dogs that weighed 28 ± 3 kg to show that an accelerometer could detect skeletal muscle fatigue in dynamic cardiomyoplasty. Through left-side thoracotomy, the heart was exposed and an electrode to sense the heartbeat was positioned on the left ventricle. A left latissimus dorsi muscle flap (LDMF) was inserted into the left chest cavity and rolled around the heart. An accelerometer was put on the rolled LDMF to sense the ventricular acceleration by contraction of the LDMF and the heart. The LDMF was stimulated under these settings: pulse width, 210 μs; stimulation output, 6 V; burst frequency, 30 Hz; burst duration, 200 ms; synchronous ratio, 1 : 4; and synchronous delay, 66 ms. Output voltage from the accelerometer was recorded 1, 3, 5, 10, and 15 min after the beginning of stimulation. Percentages of the amplitude in all dogs after 3, 5, 10, and 15 min were 81 ± 10%, 63 ± 12%, 48 ± 11%, and 45 ± 14% of the values after 1 min, respectively. Significant differences were found between the values after 1 min and those after 3 min, between the values after 3 min and those after 5 min, and between the values after 5 min and those after 10 min. This study suggests that muscle fatigue is detectable with an accelerometer in actual dynamic cardiomyoplasty.

Changes in Cholinesterase Activity, Nerve Conduction Velocity, and Clinical Signs and Symptoms in Termite Control Operators Exposed to Chlorpyrifos: Masahiro GOTOH, et al. Asahi Rosai Hospital—We have surveyed periodical medical examinations for pest and termite control operators (n=64) exposed to chlorpyrifos and other organophosphate pesticides. Distribution of serum butyrylcholinesterase (BuChE) activities of all workers ranged 0.01-1.18 (ΔpH). Serum BuChE activities in 6 workers in one termite control company were severely depressed and ranged from 0.01 to 0.21 ΔpH. Erythrocyte acetylcholinesterase (AChE) activities in 3 workers were lower than the normal range. Erythrocyte AChE activities and serum BuChE acitivities in chlorpyrifos sprayers were significantly correlated (r=0.720). In other clinical signs, blood urine nitrogen (BUN) in 4 workers and white blood cell (WBC) counts in 4 workers were abnormal. Sensory nerve conduction velocities in the sural nerve of all 6 workers were significantly reduced to 18.8-26.6 m/s in the left leg and 19.2-27.2 m/s in the right leg. In the results of ophthalmic examinations, accommodation time (both eyes) in 4 workers extended over the normal range and electroretinography (ERG) in 2 workers showed abnormal ERG including disappearance of oscillatory potential. Chlorpyrifos residue in blood in 4 operators whose serum BuChE activities ranged from 0.01 to 0.03 ΔpH were detected in the range 2-8 ng/ml. They had sprayed chlorpyrifos daily for 5 d before every blood sampling. It is suggested that serum BuChE activity and sensory nerve conduction velocity are sensitive indicators to evaluate the effects of chlorpyrifos exposure, and may be used effectively to monitor exposure and the effects of chlorpyrifos on health. (J Occup Health 2001; 43: 157-164)

症例は69歳, 男性. 67歳時, 急性心筋梗塞 (AMI) で#7にステントを留置され, 68歳時, 不安定狭心症で#6にステントを留置されている. 今回, このステントとステントの中間の部分にAMIを発症したため緊急PTCAを行ったところ, 左冠状動脈主幹部 (LMT) 解離に伴う急性冠状動脈閉塞が発生した. 心原性ショックとなったため, PCPSにより循環を補助し, LADに perfusion catheter, Cxにガイドワイヤーを挿入して緊急冠状動脈バイパス術 (CABG) を施行した. 手術は, PCPS下に体外循環確立後, VfとしてSVGをLADに吻合し, perfusion catheter とガイドワイヤーを抜去した後, 大動脈を遮断し, SVGをCx#13に吻合した. LMT解離に伴う急性冠状動脈閉塞に対するCABGにおいては, 確実な心筋保護が問題となる. perfusion catheter によりLADの灌流を維持したままVf下にSVGをLADに吻合した後に心停止とした今回のわれわれの方法は, 有用であったと考えられた.

1990年1月から1997年10月までに当科で手術を施行した遠位弓部大動脈瘤症例15例中, 胸骨正中切開のみで手術が可能であった7例 (男性5例, 女性2例, 年齢63歳から78歳まで, 平均年齢72.7歳) を対象とし, 術前評価による瘤の解剖学的特徴と到達法との関連性について検討した. 手術は, 全例, 中等度低体温脳分離体外循環下に弓部下行置換を施行. 手術死亡は1例で, 破裂例であった. 瘤への到達法と術前評価より得られた瘤の解剖学的特徴を検討すると, 瘤が嚢状で下行大動脈が瘤からほぼ正常な径で起始しており, 瘤の最大径が70mm以上で, 末梢側伸展度が気管分岐部近傍までであれば, 胸骨正中切開のみで手術が可能であると考えられた. また, Inclusion 法による末梢側吻合に際し, 下行大動脈起始部に3本のプレジェット付き支持糸を置いて, 牽引することでより良好な視野が確保でき, きわめて有用であった.

We previously successfully developed a simple nonroller extracorporeal circulation system (NRECC). In aortic arch surgery, more than two pumps are generally used for systemic perfusion and selective cerebral perfusion (SCP); we developed a new pressure-dependent perfusion system for SCP based on our NRECC and operated by a single centrifugal pump. The cerebral perfusion line was branched from the main perfusion line, and one 15 French and two 12 French cannulae were used for SCP. The perfusion pressure was regulated with a tube occluder. Afterload was changed from 30 to 80 mm Hg, the pressure of the SCP line was increased from 80 to 200 mm Hg, and flow volume was measured. When the afterload was set at 50 mm Hg, according to the increase of perfusion from 80 to 200 mm Hg, the flow volume of the 15 French cannula increased from 280 to 950 ml/min. Under the same conditions, flow volume of the 12 French cannula increased from 160 to 560 ml/min. Sufficient flow volume of the SCP lines was obtained when the SCP line pressure was over 80 mm Hg. As a result of the increased perfusion pressure, the flow volume showed a direct increase. These findings suggest that aortic arch surgery is possible using this SCP system.

A newly devised hybrid graft with high antithrombogenicity for small caliber vascular grafts was developed. The design concept was based on the incorporation of a compliant open cell structured graft, autogenous endothelial cells (ECs), and artificial basement membrane. The latter, a gel complex of type I collagen and dermatan sulfate that showed enhanced adhesion and growth of ECs but reduced platelet adhesion, was coated onto a microporous polyurethane graft (internal diameter, 3 mm; length, 4.5 cm), with near-natural compliance. Ten seeded grafts were implanted bilaterally into the carotid arteries of dogs; anticoagulant or antiplatelet therapy was not administered. This hybrid graft showed a marked improvement in patency at 1 month compared with that of simply preclotted grafts (control specimens). This result was explained by the almost complete endothelialization when the graft was implanted, a high degree of adherent strength resistance to shear stress, and a high proliferative potential. Thus, this approach of combining biomechanical and cellular engineering designs may lead to an important functional small caliber graft.

A rupture of the ascending aorta which occurred in a woman on the 13th postoperative day following a right upper lobectomy with mediastinal lymph node dissection for lung cancer is reported herein. Fortunately, the patient was rescued from a cardiac tamponade and hemothorax by emergency operation. The operative findings suggested a traumatic rupture of the aorta, however, lymph node dissection of the mediastinum could not be excluded as a possible cause. Therefore, careful mediastinal lymph node dissection should be carefully performed in operations for lung cancer.

We present a patient who suffered from composite graft infection and mediastinitis. After replacement of the infected composite graft, in addition to administration of antibiotics, continuous irrigation of the mediastinum with solutions containing povidone-iodine and cefazolin sodium and transposition of the greater omentum were performed. His postoperative course was uneventful. Combined therapies including mediastinal irrigation and omental transposition should be considered after an operation for composite graft infection complicated with mediastinitis.

A subepicardial aneurysm is a rare complication of myocardial infarction that sometimes causes a left to right shunt at the ventricular level. We report on echocardiographic observations in two recent cases of inferior myocardial infarction complicated by rupture of a subepicardial aneurysm into the right ventricle (RV). Two-dimensional and color flow Doppler images in several planes offered diagnostic characteristics of the lesion, including discontinuity of the myocardium at the neck of the aneurysm, a narrow neck relative to the diameter of the aneurysm, and a back and forth flow at the neck of the aneurysm. These techniques also provided new findings, such as a two-chambered structure of the aneurysm and a circular flow pattern within the inner aneurysmal cavity. In addition, color flow Doppler imaging showed multiple shunt flows from the aneurysm to the RV. Echocardiographically diagnosed abnormalities were verified by and successfully treated with surgery in both cases. In conclusion, echocardiography with color flow Doppler imaging may have the potential to diagnose the anatomic and hemodynamic condition of a subepicardial aneurysm. (J Am Soc Echocardiogr 1997;10:192-96.)

We recently encountered a case of idiopathic constrictive pericarditis with severe ascites. At the time of pericardectomy, intraoperative monitoring of the pressurevolume (p-v) loops of the left ventricle by the conductance catheter method ~' 2 was useful to evaluate the effects of the procedure. The patient was a 58-year-old man. At 56 years old, he had discomfort in his chest and dyspnea with exertion. The symptoms did not improve with medical manage

We investigated the effects of coenzyme Q 10 and verapamil, either alone or in combination, on cardiac function impaired by repeated ischemic arrests and reperfusion in the isolated rat heart. In the group with a single ischemic arrest, the aortic flow, cardiac output, stroke volume, coronary flow, and heart rate recovered well (72% to 100% of the prearrest values). In the repeatedarrest group, the recovery of aortic flow (24%), cardiac output (30%), stroke volume (40%), or coronary flow (63%) was much poorer than that in the single-arrest group. Pretreatment with coenzyme Q 10 given intraperitoneally improved aortic flow, cardiac output, stroke volume, coronary flow, and heart rate. The addition of verapamil to the reperfusion solution also protected the cardiac function with a decrease in heart rate. However, combination therapy with coenzyme Q 10 and verapamil further increased the recoveries of aortic flow, cardiac output, stroke volume, and coronary flow to 57%, 61%, 77%, and 84%, respectively, which were better than the values after treatment with coenzyme Q 10 or verapamil alone. We, therefore, suggest that treatment with coenzyme Q 10 or verapamil, alone or in combination, in addition to St. Thomas' Hospital solution effectively protects cardiac function impaired by repeated ischemic arrests and reperfusion.

We are developing an original nonroller extracorporeal circulation system (NRECC). However, this NRECC could not perform selective cerebral perfusion (SCP). Therefore, we added cerebral perfusion lines and an automatic pressure controller to the system. The purpose of this study was to evaluate the stability and response of the pressure controller for the SCP in simulated clinical circulation. The NRECC consists of a centrifugal pump, four isolated vacuum suction lines and a conventional module. The SCP line branches from the main perfusion tubing and divides into three lines. Cerebral perfusion is regulated by a pressure controller, which is composed of an actuator, a pressure transducer, and a personal computer. The mock circuit was primed with normal saline, and the actual SCP pressure and flow were measured when the target pressure settled at 60, 80, and 100 mm Hg. The main perfusion flow was maintained at 4 L/min and the main perfusion pressure was altered from 120 to 300 mm Hg. The pressure and flow data were recorded. The SCP pressure was maintained within +/-1.47 mm Hg when the set pressure was 80 mm Hg. Fluctuation of flow in the SCP line was within the range of +/-2.8%. The time needed to reach the steady state pressure was 8+/-1 seconds when the initial setting of the roller occluder was full-open, and it took only 3+/-1 seconds to reach the next initial set pressure. We have developed the NRECC-SCP system. The SCP pressure is stable and quickly reaches steady state via the pressure controller. This system is useful for extracorporeal circulation during aortic arch operation.

肝部下大静脈閉塞によるBudd-Chiari症候群を合併した肝細胞癌の1例を報告した.症例は46歳の男性,主訴は下肢の浮腫である.入院時現症では貧血,黄疸はないが,肝脾腫と両下肢の浮腫を認めた.検査所見ではT-Bilirubin 2.7mg/dl, ICG R15'28.6%と異常値を示し,腹部超音波検査,腹部CT,血管造影などの画像診断で肝右葉に肝細胞癌が認められた.また,下大静脈造影で肝部下大静脈は,1.5cmにわたり完全閉塞をきたしていた.右開胸と上腹部傍正中切開にて開胸開腹を行い,肝右葉腫瘤の核出と下大静脈右房間に人工血管を用いてバイパス手術を行った.切除肝には1.9×1.6cmの被膜におおわれた腫瘤が認められた.バイパス後の下大静脈圧は23cmH2Oから12cmH2Oに低下した.術後10ヵ月経た現在,再発はなく,グラフト内の血流も良好で症状の改善が認められている.

Aneurysms of the interatrial septum are uncommon lesions that are often accompanied by other cardiac anomalies or systemic thrombosis. The authors report 1 case of atrial septum aneurysm that was diagnosed by two-dimensional contrast echocardiography. At surgery a membrane-like, fenestrated aneurys mal protrusion to the right atrium without thrombosis was seen. The atrial septum was closed without using an artificial patch after some of the aneurysm with fenestrations was resected.

Chlordane has been widely used to protect soil and house foundations against termite infestation. Pest control operators (PCOs) are occupationally exposed to chlordane. The relationship between chlordane and its metabolites in blood of PCOs and spraying conditions were investigated. Chlordane and its metabolites were detected in the blood of some chlordane-exposed PCOs, but not in that of the controls. Trans-nonachlor and the metabolites oxychlordane and heptachlor epoxide were detected in the blood of PCOs. Total concentration of chlordane and its metabolites in blood (trans-nonachlor + oxychlordane + heptachlor epoxide) was less than 5.6 ppb (mean: 0.89 ppb). The concentration of chlordane and its metabolites in blood of chlordane-exposed PCOs was significantly correlated with the number of spraying days and the amount of chlordane sprayed, particularly with a large correlation coefficient (r = 0.81, P less than 0.001) with the spraying days in the three months prior to the medical examination. The concentration of chlordane and its metabolites in blood is considered to be a useful indicator of biological monitoring for chlordane exposed workers (PCOs).

The authors examined the physiological changes of men riding motorcycles carrying different loads. Nine healthy professional riders were the subjects. They used professional Honda MD 90B-90CC motorcycles. Each subject made test rides with the loads of 0, 10, 15, and 20 kg, taken at random, on a concrete road for 20 min at a speed of 30 km/h. The environmental temperature at the time of the test, skin temperature, vibration sense threshold at a vibration level of 125 Hz, critical flicker fusion frequency, pinching power, grasping power, pulse rates, and blood pressure were measured. The pulse rates were significantly different for the rides with the four different loads, and the changes in pulse rate after the ride with the loads of 10 and 20 kg were comparatively higher than those before the ride. The changes of systolic blood pressure after the rides with the loads of 15 and 20 kg were significantly higher than those before the rides. The other changes observed were not significantly different.

We measured vibratory sense thresholds (VSTs) at 63Hz and 125Hz on the third fingertip of the right hand and on the third toe of the right foot of 74 male workers. The subjects were workers engaged in manufacturing ceramic color and transfer printing paper, whose blood lead (Pb-B) levels were 2-58 micrograms/dl. They were divided into three groups according to the Pb-B levels, namely, below 9, 10-19, and 20 micrograms/dl or more. For statistical analysis, simple and partial correlations, and Scheffé's multiple comparison between the least squares means were used. The VSTs on the fingertip as well as on the toe showed a significant correlation with age. The VSTs at 125Hz on the fingertip were also significantly correlated with alcohol consumption and cigarette smoking. Controlling for age, systolic blood pressure, alcohol consumption and smoking habit, a significant dose-effect relationship was observed between the VSTs at not only 63Hz but at 125Hz on the fingertip, and each of the corresponding Pb-B levels. A similar tendency was also observed at the two frequencies on the toe. The measurement of VSTs was considered to be an effective screening test for sensory nerve disorders caused by lead poisoning.