We report a case of angiosarcoma of the right atrium manifesting as cardiac tamponade. The patient was a 34-year-old woman. Echocardiography, CT scans, MRI and coronary angiography revealed a tumor arising in the right atrium. Radical excision of the tumor with cardiopulmonary bypass was performed. The resected tumor measured 5×6×3cm, and microscopic examination revealed angiosarcoma. Adjunctive radiation therapy was performed and she had high quality of her life for more than 2 years. However, she died of hemorrhage caused by liver metastasis of the tumor on the 29th postoperative month.

A case of chylorrhea arising after median sternotomy for treatment of atrial septal defect was reported. The patient was a 55-year-old male, who had visited our outpatient clinic with a complaint of edema in the bilateral lower legs in June 1990. Under a diagnosis of atrial septal defect, a patch closure was performed in November. On the 5th postoperative day, a full liquid diet was started. Two hours and a half after the food intake, the drainage from a tube inserted into the anterior mediastinum turned milky white. Chylorrhea was diagnosed. The patient was placed in N.P.O. and maintained by an intravenous hyperalimentation. Drainage of 250-350ml/day milky white fluid persisted until the 14th postoperative day, when a 5cm removal of the mediastinal tube resulted in dramatic decrease in drainage. Thus chylorrhea in this case was cured by conservative treatment.

A Pulmonary arterial flow-directed catheter (Oxymetry 93A-741-7.5F), combining the fiberoptic reflectometric system of continuous measurement of mixed venous blood oxygen saturation (SvO₂) was used for hemodynamic measurements including thermodilution cardiac output estimation and hemoglobin value in 21 cases of open heart surgery. Immediately after open heart surgery there was low correlation between Hb (hemoglobin value) and SvO₂ (r=0.513, p<0.05). However there was no correlation between SvO₂ and cardiac function (pulmonary capillary wedge pressure and cardiac index). With almost normal Hb (10-13g/dl) the average cardiac index (CI) in cases of SvO₂ less than 60% was 2.47l/min/m² which was significantly lower than those with SvO₂ more than 60% (p<0.01). With normal CI (2.5-4.0l/min/m²) the average Hb in cases of SvO₂ less than 60% was 7.40g/dl which was significantly lower than those of more than 60% (p<0.01). This study suggested that there is low cardiac function or severe anemia in the state of SvO₂ less than 60%.

A 59-year-old man was hit by a car in the back of the knees. He had a cold sensation and pulselessness in the right leg. He did not have bone fractures, but had dirty skin injuries in the back of bilateral knees. DSA revealed complete obstruction of the right popliteal artery and good collateral flow to the peripheral arteries in the right lower leg. We did not perform emergency operation because of the good collateral flow and dirty skin injuries. After the healing of the skin injuries, we performed popliteal artery reconstruction with autologous saphenous vein graft. The postoperative course was uneventful with successful patency of the graft.

It had been proposed by Kurata that relative threshold value F_th of single motor units depends on the gradient G (kg/sec) of the tension increase of muscle in such a manner as
F_th (≡T.G) =ρG^λ
Here T₁ is the time interval from the onset of EMG to the moment of recruitment of a motor unit and ρ is a proportional constant. The motor unit with a positive/negative value of λ is characterized to be static/phasic.
Morimoto and Hasegawa reported that the above relation also holds for the relaxation period, provided that Ftn and G are replaced by the tension at the moment of silence and the absolute value of G, respectively. In this case, the motor unit with a positive/ negative value of λ is characterized to be phasic/static.
In order to investigate the characteristics of motor units during relaxation period under the influence of pre-relaxation states, such as the increase of tension up to 4kg at the gradient of 0.5kg/sec and the state sustained at 4.0kg for 30sec. Single motor units of m, vastus medialis were studied by the same method as that of Morimoto and Hasegawa.
The following results were obtained;
1) Both at contraction and relaxation periods, the above relation was confirmed.
2) The motor unit with characteristics of recruitment modes was influenced by the pre-relaxation state, but its tendency was not definite. These results suggest that phasic/static characteristics of motor units are not stationary but fluctuate depending on the pre-relaxation states.

In this study, the relationships between the contractile properties of human motor units and their discharge patterns, characteristics of recruitment and others were examined. Action potentials of single human motor units in m, extensor digiterumwere detected by use of an inserted electrode. Tension curves of single motor units were recorded under the conditions that tension in finger extension was gradually increased, and that the subject relaxed his muscle as soon as he observed a sweep on a Braun tube triggered by the action potential of a single motor unit. About 100 twitch tension curves were summed up to obtain the average tension curve of a single motor unit. The τ-S diagrams were obtained from the mean discharge intervals (τ) of motor units at various sustained tensions and their standard deviations (S) . The λ values were also obtained from the relation F_th (-T₁G) =ρG^λ.
It was observed that the contraction time of the twitch tension curve of single human motor unit in a muscle was nearly proportional to τs (the τ values at a constant S value) . We presume that the regularity of discharging of motor unit affects the contraction speed in human muscle, because the motor unit with more regular discharging has longer contraction time of twitch.

This report documents a case of three-channeled aortic dissection. The diagnosis of dissecting aneurysm was made by chest X-P and CT to 70-year-old man, with a chief complaint of back pain. Aortogram showed aortic aneurysm (DeBakey type IIIb), which had an entry at distal of the beginning of the left subclavian artery. Though we had given a pressure control therapy, the patient died on the 5th day of the admission. At autopsy, a new dissection was found in the chronic dissecting outer wall, forming three channeled dissection and rupture was there. Three-channeled dissection is very rare, only 8 cases including ours have been reported so far. From this case, we learned it very difficult to diagnose and treat it.

Aortic valve replacement was carried out for aortic regurgitation in Behçet's disease. A prosthetic valve was fixed using reinforced felt-strip mattress sutures. Difficulty to ensure adequate myocardial protection due to ostial stenosis in the right coronary artery resulted in the occurrence of intraoperative myocardial infarction. Right ventricular assist with the help of a centrifugal pump was employed to obtain successful recovery from right cardiac failure. It was noted that at operation attention should have been paid to the aortic valve and also to abnormalities of the coronary artery and that control of the inflammatory reaction by steroids was essential before and after the operation.

We studied the effects of granulocytic elastase (GEL) and fibronectin (FN) on the coagulation and fibrinolytic system when using cardiopulmonary bypass (CPB). Blood sampling was performed before CPB (Pre), just after CPB (Post) the 1st postoperative day (PD1) and the second postoperative day (PD2). Laboratory parameters were GEL, FN, fibrinogen (Fib), prothrombin time (PT), fibrin degradation products (FDP), D dimer (D-D), α2 plasmin inhibitor plasmin complex (PIC) and antithrombin III (AT III). The level of GEL was highest and that of FN was lowest at Post. The levels of Fib, PT and AT III were lowest and that of PIC was highest just after CPB. The levels of FDP and D-D were highest on PD1. The levels of GEL and D-D correlated just after CPB and on PD1 and PD2. The level of GEL correlated with that of PIC on PD1. These results demonstrated that the level of FN decreased with CPB. And it was expected that CPB time affected the level of GEL. The levels of GEL affects D-D and PIC which are fibrinolysic factors particularly related to secondary fibrinolysis.