• Proceedings of the KOSOMBE Conference
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• v.1996 no.05
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• pp.88-90
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• 1996

The right and left atrial pressures are important parameters in automatic control of a total artificial heart (TAH) within normal physiological ranges. Our TAH is composed of a moving actuator, right and left ventricles and the interventricular space enclosed by a semi-rigid housing. During operation of the TAH, the jnterventpicular space's volume is changed dynamically by the difference between the ejection volume of one ventricle and the inflow volume of the other. Therefore, the changes in pressure of the interventricular space is related to both atrial pressures. We measured the interventricular pressure (IVP) waveform using a pressure sensor and attempted to indirectly estimate the changes of atrial pressures. This method has an advantage that the sensor does not contact the blood directly. Furthermore, the IVP waveforms have its zero baseline in each pump cycle, thus the pressure measurements are free from the transducer drift problems by measuring the peak pressure from these baseline values. From the In vitro experiments, we found that the IVP waveform contained several useful parameters such as negative peak, dP/dT on the initial break, the area enclosed by the profile in each stroke, which are associated with atrial pressures and the filling conditions of the ventricles. The measured atrial pressures were linearly related to the negative peak of the interventricular pressure.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.05
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• pp.82-83
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• 1996

In this paper, we present a simplified model for complicance determination of the moving-actuator type totally implantable artificial heart (TAH). The modeling equations are derived from the mechanics and geometry of the TAH components. The interventricular pressure and volume are computed for determining the compliance of the interventricular space using this model. The model is capable of generating realistic hemodynamic variables such as the left atrial pressure and interventricular pressure and is proved to be acceptable. This model can be used as an initial step for analyzing characteristics of the moving-actuator type TAH.

• Journal of Veterinary Clinics
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• v.15 no.1
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• pp.14-21
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• 1998

Ultrasonogram for kidney, spleens liver, intestine and heart was evaluated 11 Chriu horses and 14 Thoroughbred horse. The kidney was determined at both flan and both 17th intercostal spaces. The spleen was determined at the left 13-17 intercom spacer and the liver was determined at the right 7-13 intercostal space. The heart was determined at the right 4-6 intercostal space and left 3-6 intercostal space. The length, of rig kidney at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 16.2, 12.6, 13.1 and 11.2 mm, respectively. The width of right kidney at the Thoroughbed horse, Thorughbred foul, Cheju horse and Cheju foul were 5.4, 4.3, 4.6 and 4.2 mm, respectively. The depth of right kidney at the Thoroughbred horsed Thoroughbred foul, Cheju horse and Chrju foul were 5.2, 4.4, 4.5 and 4.3 mm, respectively. Similar ultrasonographic measurements were obtained for the left kidney, The left ventricular end-diastolic diameter at the Thoroughbred horse, Thoroughbred fouls Cheju horst and Cheju foul were 107, 83, 85 and 73 mm, respectively. The left ventricular end-systolic diameter were at the Thoroughbred horse, Thoroughbred foul, Cheiu horse and Cheiu foul were 63, 52, 53 and 45 mm, respectively. Also, the interventricular septum in end-diastole, interventricular septum in end-systoles left ventricular wall end-diastoles left ventricular wall end-systoles right ventricular end-diastole diameter, aorta and left atrium at t Thoroughbred horse, Thoroughbred foul, Chriu horse and Chriu foul were measured. Experimental renal stone and enterolith of colon were observed by ultrasonography.

• Journal of Biomedical Engineering Research
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• v.19 no.4
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• pp.385-391
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• 1998

A new balancing method of atrial pressures balancing for the moving actuator total artificial heart(TAH) without an extra compliance chamber was developed. The asymmetric operation of the pendulous moving actuator have made it possible to compensate the left and right pump output difference by utilizing the interventricular air space as an internal compliance chamber in a pump housing. Furthermore, the balancing performance between left and right pump outputs is increased through the improvement of the flexibility of part of the polyurethane housing. However, the increase of the flexibility of the pump housing causes a little loss of the cardiac output due to the reduction of active filling property. In this paper., a good condition between the balance and pump output performance is evaluated by adjusting the air volume in the interventricular space through a series of in vitro experiments. This new pump was implanted in a sheep weighting 63kg, and it survived for 3 days and the average cardiac output during postoperative days was about 4.2 L/mim with the atrial pressures under 15 mmHg.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.11
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• pp.216-218
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• 1995

A new atrial pressures balancing method for moving actuator total artificial heart(TAH) without an extra compliance chamber is developed. The structural characteristics of the pendulous moving actuator have made it possible to compensate the left and right pump output difference by utilizing the interventricular air space as an internal compliance chamber in a pump housing. Furthermore, the balancing performance is increased through the improvement of the flexibility of part of the polyurathane housing. However, the increase of the flexibility of the housing causes a little loss of the cardiac output due to the reduction of active filling performance. In this paper, a good condition between the balance and pump output performance is evaluated by adjusting the air volume in the interventricular space through a series of in vitro experiment.

• Journal of Veterinary Clinics
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• v.12 no.1
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• pp.861-876
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• 1995

This study was carried out to get fundamental information about the normal ultrasonogram of the liver and heart in Korean native cattle and calves. The interventricular septum, left ventricular internal diameter, left ventricular free wall thickness, aortic diameter, left atrial diameter, and right ventricular internal diameter of hear in 10 Korean native calves were determined at 4-5 right intercostal spare by use of ultrasonography. The caudal vena cava, portal vein, gallbladder, liver of 9 Korean native cattle and 10 calves were determined at 12, 11 and 10th intercostal spares by use of ultrasonography. Cursor-directed M-mode and gray-scale, B-mode ultrasonograms were obtained with electronic scanning ultrasound equipment with a 3.5 or 5.0-MHz convex transducer. The results obtained through the experiments were summarized as follows: 1. The result of ultrasonographic examination of the korean native calves' heart 1) Interventricular septum in systole and diastole was 1.23 and 0.81 cm, respectively(vc=28.84, 17.4). 2) Ventricular internal diameter in systole and diastole was 2.50 and 4.91 cm, respectively(vc=17.44, 12.73). 3) Left ventricular free was thickness in systole and diastole was 1.44 and 0.92 cm, respectively(vc=26.85, 23.54). 4) Aortic diameter was 2.69.m, .rspectevely(vc=11.29). 5) Left atrial diameter was 1.82 cm(vc=15.31). 6) Right ventricular internal diameter in systole and diastole was 1.12 and 1.9 cm, respectively(vc=33.71, 24.43). 3. Ultrasonographic measurments of caudal vena cava, portal vein, gallbladder of Korean native calves 1) Dorsal margin of caudal vena cava at the 12, 11 and 10th intercostal space was 13.5, 15.3 and 18.1 cm, respectively(p<0.01). 3) Depth of caudal vena cava at the 12, 11 and 10th intercostal space was 4.4, 4.5 and 4.6 cm, respectively. 3) Diameter of caudal vena cava at the 12, 11 and 10th intercostal space was 11.6, 1.7 and 1.6 cm, respectively. 4) Dorsal margin of portal vein at the 12, 11 and 10th intercostal space was 16.2, 18.6 and 21.4 cm, respectively(p<0.01) 5) Depth of portal vein at the 12, 11 and 10th intercostal spare was 4.5, 4.4 and 3.9 cm respectively. 6) Diameter of portal vein at the 13, 11 and 10th intercostal space was 2.1, 2.2 and 1.9 cm respectively. 7) Dorsal margin of gallbladder at the 11 and 10th intercostal space was 23.6 and 23.9 cm, respectively(p<0.01), 8) Longitudinal diameter of gallbladder at the 11 and 10th intercostal space was 7.1 and 5.9 cm, respectively(p<0.05). 9) Transverse diameter of gallbladder at the 11 and 10th intercostal space was 2.4 and 2.1 cm respectively(p<0.01). 3. Ultrasonographic measurments of caudal vena cava, portal vein, gallbladder of Korean native cattle 1) Dorsal margin of caudal vena cava at the 12 and 11th intercostal space was 22.2, and 25.4 cm, respectively(p<0.01). 2) Depth of caudal vena cava at the 12 and 11th intercostal space was 103 and 11.1 cm, respectively(p<0.01). 3) Diameter of caudal vena cava at the 12 and 11th intercostal space was 3.1 and 3.0 cm, respectively. 4) Dorsal margin of portal vein at the 12 and 11th intercostal space was 29.3 and 32.9 cm, respectively(p<0.01). 5) Depth of portal vein at the 12 and 11th intercostal space was 9.6, and 9.2 cm, respectively. 6) Diameter of portal vein at the 12 and lith intercostal space was 3.4 and 3.3 cm, respectively. 7) Dorsal margin of gallbladder at the 11 and 10th intercostal space was 43.1 and 45.5 cm, respectively(p<0.01). 8) Longitudinal diameter of gallbladder at the 11 and 10th intercostal space was 10.1 and 9.4 cm, respectively. 9) Transverse diameter of gallbladder at the 11 and 10th intercostal space was 4.0 and 3.7 cm, respectively. 4, Ultrasonogaphic measurments of dorsal margin, ventral margin, size and angles of the Korean native calves' liver. 1) Dorsal margin of liver at the 12, 11 and 10th intercostal space was 11.0, 9.6, and 12.4 cm, respectively(p<0.01). 2) Ventral margin of liver at the 12, 11 and 10th intercostal spate was 20, 24 and 26.1 cm, respectively(p<0.01). 3) Size of the liver at the 12, 11 and 10th intercostal space was 9.0, 14.6 and 13.8 cm, respectively(p<0.01). 4) Angle of liver at the 12, 11 and 10th intercostal space was 40, 46 and 37, respectively(p<0.01). 5. Ultrasonographic measurmants of dorsal margin, ventral margin, size and anglses of the korean native cattle's liver 1) Dorsal margin of the liver at the 12, 11 and 10th intercostal space was 14.4, 18.2 and 26, 3 cm, respectively. 2) Ventral margin of liver at the 12, 11 and 10th intercostal space was 41.1, 46.4 and 49.3 cm, respectively(p<0.01). 3) Size of the liver at the 12, 11 and 10th intercostal space was 26.8, 28.2 and 23.2 cm, respectively(p<0.01). 4) Angel of liverat the 15, 11 and 10 intercostal space was 41, 40.6 and 35.7, respectively(p<0.05). It was concluded that the ultrasonographic values oletermined in this study can be used as references for the diagnosis of morphologic changes in the hear and liver in korean native calves, and in the liver in korean native rattle.

• Journal of Chest Surgery
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• v.14 no.1
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• pp.49-59
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• 1981

This is one case report of surgically treated partial atrioventricular canal. The 22 year-old male patient had no definitive history of frequent respiratory infection and cyanosis in his early childhood. Since his age of 7 years, dyspnea was manifested on exertion. First appearance of congestive heart failure was at his age of 16 years old. The physical examination revealed that the neck veins were distended and heaving of precordium. A thrill was palpable on the left 3rd-4th intercostal space extending from the sternal border toward the apex and Grade IV/VI systolic ejection murmur was audible on it. Neither cyanosis nor clubbing was noted. Liver was palpable about 5 finger breadths. Chest X-ray revealed increased pulmonary vascularity and severe cardiomegaly (C-T ratio = 74%). EKG revealed LAD, clockwise rotation, LVH and trifascicular block. Echocardiogram showed paradoxical ventricular septal movement, narrowed left ventricular outflow tract and abnormal diastolic movement of the anterior leaflet of mitral valve. Right heart catheterization resulted in large left to right shunt (Qp : Qs = 5.7: 1), ASD and moderate pulfllonary hypertension. Finally, left ventriculogram revealed typical goose neck appearance of left ventrlcalar outflow tract. On Oct. 10, 1980, open heart surgery was performed. Operative findings were: 1. Large primum defect ($6{\times}5$ Cm in diameter) 2. Cleft on the anterior leaflet of mitral valve. 3. The upper portion of ventricular septum was descent but no interventricular communication. 4. Downward attachment of the atrioventricular valves on the ventricular muscular septum. 5. Medium sized secumdum defect ($2{\times}1$ Cm in diameter). The cleft was repaired with 4 interrupted sutures. The primum defect was closed with Teflon patch and the secundum defect was closed with direct suture closure. Postoperatively atrial flutter-fibrillation in EKG and Grade U/VI apical systolic murmur were found. The postoperative course was uneventful and discharged on 29th postoperative day in good general conditions.