• Korean Journal of Veterinary Research
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• v.39 no.2
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• pp.390-393
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• 1999

Transcolonic scintigraphy using $^{99m}Technetium$ pertechnetate ($^{99m}TcO_{4}$) was performed in 5 dogs with portosystemic shunts. In all dogs, the activity in the heart was seen before liver activity. Also time activity curve was revered. The mean shunt index in 5 dogs was 82.3% (range 79.6~87.1%). Transcolonic scintigraphy is quick, simple and useful diagnostic method for canine portosysternic shunts.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.905-906
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• 2007

An intercomparison of ac shunts between the National Research Council of Canada and Korea Research Institute of Standards and Science is presented. The comparison was performed for the recently develop 1 A and 5 A current shunts at KRISS. The results of the both phase angle and ratio error of the resistive shunts are agree within the level of $\pm$1.5ppm and $\pm$5ppm respectively at 50 Hz.

• Journal of Chest Surgery
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• v.21 no.1
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• pp.136-142
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• 1988

Between February, 1983, and March, 1987, thirty-one systemic-pulmonary shunts were performed in 28 patients with cyanotic congenital heart disease. Age ranged from 8 months to 28 years [mean age, 5.4 years, Weight ranged from 7 kg to 48 kg [mean weight, 16kg]. There were 4 classic Blalock-Taussig shunts, 5 central polytetrafluoroethylene shunts, 1 aorta-right pulmonary artery shunt with graft, and 21 modified Blalock-Taussig shunts. One patient required another shunt immediately due to insufficient pulmonary blood flow with patent graft. There was no postoperative death. Conduit diameters included 4mm [2 cases], 5 mm [22 cases], and 6 mm [3 cases]. Long term follow up was available in 27 patients [96.4%] with mean period of 20 months [range, 4 months to 49 months]. The effectiveness of shunt was evaluated by cardiac catheterization with angiography [15 patients] or clinically. They showed improvement of systemic oxygen saturation values by 12% and decrease of hemoglobin by 2.3gm/dl [P<0.01]. There were 2 shunt occlusion in central shunts at 32 and 48 months respectively, and one narrowing of graft in modified Blalock-Taussig shunt at 12 months. The patency rate was 91.6% at 24 months for 5 mm grafts in modified Blalock-Taussig shunt.

• Journal of Chest Surgery
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• v.15 no.2
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• pp.194-203
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• 1982

In this investigation we undertook to evaluate the utility of radionuclide cardiac angiography in the detection of cardiac shunts before and after surgical correction. Time-activity curves of ventricles and lungs were evaluated after bolus intravenous injection of 99mTc-human serum albumin in 512 preoperative patients and 551 post-operative patients. Omitting 31 cases of technical failure due to poor bolus, we detected shunts in 459 cases of 481 preoperative evaluations, so the detectability was 95.4%. The cases which couldn`t be detected by this method had small amount of shunt. Also the degree of shunt detected by radioisotope methods were well correlated with oxymetry method. [r=0.89, p<0.01 ] In postoperative evaluations, 18 out of 411 patients with left to right shunt and 10 out of 140 right to left shunt were found to have remnant shunts with radionuclide cardiac angiography. Of the 28 cases with failed operation, 2 were confirmed in reoperation, 2 by cardiac catheterization, 2 by two -dimensional echocardiography. All except one .f these patients had membranous ventricular septal defects and those with left to right shunts had moderate to severe pulmonary hypertension and shunt amount. Also those had larger septal defects than control group. We consider that radionuclide cardiac angiography is a simple and noninvasive method which can show the preoperative diagnosis and postoperative follow up of cardiac shunts.

• The Korean Journal of Nuclear Medicine
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• v.21 no.2
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• pp.155-165
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• 1987

The noninvasive nature of the radionuclide angiocardiography provided a useful approach for the evaluation of left-to-right cardiac shunts (LRCS). While the qualitative information can be obtained by inspection of serial radionuclide angiocardiograms, the quantitative information of radionuclide angiocardiography can be obtained by the analysis-of time-activity curves using advanced computer system. The count ratios method and pulmonary-to-systemic flow ratio (QP/QS) by gamma variate fit method were used to evaluate the accuracy of detection and localization of LRCS. One hundred and ten time-activity curves were analyzed. There were 46 LRCS (atrial septal defects 11, ventricular septal defects 22, patent ductus arteriosus 13) and 64 normal subjects. By computer analysis of time-activity curves of the right atrium, ventricle and the lungs separately, the count ratios modified by adding the mean cardiac transit time were calculated in each anatomic site. In normal subjects the mean count ratios in the right atrium, ventricle and lungs were 0.24 on average. In atrial septal defects, the count ratios were high in the right atrium, ventricle and lungs, whereas in ventricular septal defects the count ratios were higher only in the right ventricle and lungs. Patent ductus arteriosus showed normal count ratios in the heart but high count ratios were obtained in the lungs. Thus, this count ratios method could be separated normal from those with intra cardiac or extracardiac shunts, and moreover, with this method the localization of the shunt level was possible in LRCS. Another method that could differentiate the intracardiac shunts from extracardiac shunts was measuring QP/QS in the left and right lungs. In patent ductus arteriosus, the left lung QP/QS was higher than those of the right lung, whereas in atrial septal defects and ventricular septal defects QP/QS ratios were equal in both lungs. From this study, it was found that by measuring QP/QS separately in the lungs, intracardiac shunt could be differenciated from extracardiac shunts.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.25 no.2
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• pp.147-162
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• 2022

Purpose: To design a prospective study on endovascular closure of congenital portosystemic shunts. The primary endpoint was to assess the safety of endovascular closure. The secondary endpoint was to evaluate the clinical, analytical and imaging outcomes of treatment. Methods: Fifteen patients (age range: 2 days to 21 years; 10 male) were referred to our center due to congenital portosystemic shunts. The following data were collected prior to treatment: age, sex, medical history, clinical and analytical data, urine trimethylaminuria, abdominal-US, and body-CT. The following data were collected at the time of intervention: anatomical and hemodynamic characteristics of the shunts, device used, and closure success. The following data were collected at various post-intervention time points: during hospital stay (to confirm shunt closure and detect complications) and at one year after (for clinical, analytical, and imaging purposes). Results: The treatment was successful in 12 participants, migration of the device was observed in two, while acute splanchnic thrombosis was observed in one. Off-label devices were used in attempting to close the side-to-side shunts, and success was achieved using Amplatzer™ Ductus-Occluder and Amplatzer™ Muscular-Vascular-Septal-Defect-Occluder. The main changes were: increased prothrombin activity (p=0.043); decreased AST, ALT, GGT, and bilirubin (p=0.007, p=0.056, p=0.036, p=0.013); thrombocytopenia resolution (p=0.131); expansion of portal veins (p=0.005); normalization of Doppler portal flow (100%); regression of liver nodules (p=0.001); ammonia normalization (p=0.003); and disappearance of trimethylaminuria (p=0.285). Conclusion: Endovascular closure is effective. Our results support the indication of endovascular closure for side-to-side shunts and for cases of congenital absence of portal vein.

• The Korean Journal of Nuclear Medicine
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• v.13 no.1_2
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• pp.7-14
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• 1979

Radionuclide cardiac angiography has distinct advantages in safety, patient comfort, cost and ease of performance. This method offers diagnostic accuracy equivalent to that of cardiac catheterization. By this method the qualitative and quantitative diagnosis of the cardiac shunts are available. Also for it is repeatable with ease and more physiologic, it has application in following pre- and post-operative shunt patients. We performed the radionuclide cardiac angiographies in 147 cases of heart diseases and 26 cases of normal group. 1. The detection of left-to-right shunt was possible in 22 of 24 patients, and 2 patients were not diagnosed due to small shunt amount. (Qp/Qs<1.3) In 21 patients of right-to-left shunt, all were diagnosed by radionuclide cardiac angiography. 2. With the pulmonary time-activity curve, $C_2/C_1$ ratio was calculated. In normal control group, a range of $C_2/C_1$ ratios of $21{\sim}38%$ was established with a mean value of $28.6{\pm}4.6%$. In patients with left-to-right shunts determined by catheterization data, the range of $C_2/C_1$ ratio was $33{\sim}90%$, with a mean value of $67.8{\pm}12.2%$. 3. In 8 cases of left-to-right shunt, $Q_p/Q_s$ ratios determined by radionuclide cardiac angiography were compaired with those of cardiac catheterization. The correlation coefficient was 0.907. (P<0.001) 4. Postoperative radionuclide cardiac angiographies were done in 21 cases. 3 of 13 patients with left-to-right shunts were found to have residual shunts. 8 patients with right-to-left shunts were confirmed to have no residual shunt.

• Journal of Chest Surgery
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• v.18 no.2
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• pp.314-319
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• 1985

Nineteen patients with various types of cyanotic congenital heart disease underwent systemic-pulmonary artery shunts with a microporous polytetrafluoroethylene [PTFE] graft between September, 1983, and April, 1985. Age ranged from 3 months to 18 years, and seven of them were less than 12 months old. There were seventeen Great Ormond Street type of modified Blalock-Taussig shunts, and two central polytetrafluoroethylene shunt [ascending aorta-right pulmonary artery]. There was one postoperative death [1/19=5.3%] in a 10 Kg child born with pulmonary atresia and ventricular septal defect associated with patent ductus arteriosus. He had another anomaly of imperforated anus. Relief from cyanosis was achieved in other eighteen patients with variable degree. Eighteen survivors have been followed up from 1 month to 19 months. Clinical status, auscultation, oxygen partial pressure of arterial blood, and hemoglobin have been used to establish shunt patency in all survivors. By above criteria, all survivors have good patent shunt.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1445_1446
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• 2009

This paper represents the step response characteristics of shunts for impulse current. This work is aimed at the development of the reference measuring system(RMS) for impulse current rated 10 kA at 1/$20{\mu}s$, 100 kA at 4/$10{\mu}s$, 20 kA at 8/$20{\mu}s$, 40 kA at 30/$80{\mu}s$. According to the IEC 60060-2, the step response characteristics was assessed. As results of the test, the step response characteristics of newly developed shunts for impulse current satisfied requirements of RMS.

• Journal of Chest Surgery
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• v.11 no.2
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• pp.227-231
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• 1978

Since January 1973 we have performed 47 arteriovenous shunts and 22 arteriovenous fistulas for 57 patients with acute or chronic renal failure. Of these 57 cases, 50 cases had chronic renal failure and the other 7 cases had acute renal failure. The most frequent complications after operations were thrombosis, bleeding and infection. Less frequently dislodgement of shunt and aneurysmal change of the fistula were found. After 47 arteriovenous shunts, 21 those complications [44%] were found. On the other hand after 22 arteriovenous fistulas, 5 complications were found. Now we are using the arteriovenous shunt only for the patients who need emergency short term hemodialysis and temporary dialysis until arteriovenous fistula could be used.