• Childhood Kidney Diseases
• /
• v.2 no.2
• /
• pp.138-144
• /
• 1998

Purpose : The use of cyclosporine and mitomycin in various immunologic or neoplastic disorders has been known to cause wide-ranged nephrotoxic effects including thrombotic microangiopathy. However, the mechanism of nephrotoxicity of these drugs has not been studied adequately, so that present experimental study has been undertaken to find out whether these drugs can cause direct damage to the kidney and to clarify the pathogenetic mechanism of nephrotoxic effect of these drugs. Materials and methods : Sprague-Dawley rats weighing 250-300 gm were used for experimental animals and unilateral renal perfusion technique, modified from the method described by Hoyer et al was used. Isolation of left kidney from systemic circulation was made by clamping aorta and left renal vein and a hole was punctured in the anterior wall of the left renal vein. Cyclosporine (2.5 mg in 4 ml solution) and mitomycin (1.6 mg in 4ml solution) were infused through left renal artery and normal saline was used in control rats. Forty-eight hours after infusion of the drugs, animals were sacrificed and left kidney removed and processed for histologic examination. Total ischemic time of left kidney was less than 15 minutes: Results : Cyclosporine-perfused group showed severe swelling of glomerular endothelial ceil along with swelling of glomerular epithelial cell and interstitial vascular endothelial cell. Mitomycin-perfused group also showed severe swelling of glomerular endothelial and epithelial cells. And in addition to these findings, they demonstrated platelets aggregation, swelling and degranulation of platelets and fibrin accumulation in some of the capillaries, indicating occurrance of thrombotic microangiopathy. Conclusion : present experiment indicates that cyclosporine and mitomycin can cause direct toxic injury to renal endothelial cell. And this direct toxic damage to endothelial cell seems to be an important initiating event for the development of thrombotic microangiopathy.

• Journal of Chest Surgery
• /
• v.31 no.7
• /
• pp.660-667
• /
• 1998

Background: This study is to evaluate the effectiveness and application of Lecompte procedure as a treatment for various complex cardiac anomalies with pulmonary outflow tract obstruction. Methods: Between July 1988 and December 1997, 44 patients underwent Lecompte procedure in Seoul National University Children's Hospital. The male to female ratio was 24 to 20 and the mean age was 29.2 months(range, 3 to 83). Of these patients, 28(63.6%) had transposition of great arteries with ventricular septal defect and pulmonary stenosis(or pulmonary atresia), 14(31.8%) had double outlet right ventricle with pulmonary stenosis(or pulmonary atresia), and so on. The principles of the technique are 1) extension of the ventricular septal defect or conal resection, 2) construction of a intracardiac tunnel connecting the left ventricle to the aorta, and 3) direct connection, without a prosthetic conduit, of the pulmonary trunk to the right ventricle. Results: There were 3 in-hospital deaths and their causes were sustained hypoxia, myocardial failure, and sepsis, respectively. There was 1 late death due to sepsis. Reoperations were performed in 6 patients who had pulmonary outflow tract obstructions(4 cases), residual muscular ventricular septal defect(1 case), and recurrent septic vegetation(1 case). The cumulative survival rates by the Kaplan-Meier method were 92.7%, 92.7%, and 92.7% at 1, 2, and over 4 years. The reoperation free survival rates were 92.7%, 92.7%, and 70.2% at 1, 3, and over 5 years. Among the risk factors for the operative death, aortic cross clamping time had statistical significance(p<0.05) and all the risk factors for the recurrent pulmonary stenosis such as age, pulmonary artery index, and materials used for the pulmonary outflow tract reconstruction had no statistical significance(p>0.05). Conclusions: Our review suggests that Lecompte procedure is an effective treatment modality for various complex cardiac anomalies with pulmonary outflow tract obstruction. Repair in early age is possible and the rates of mortality and morbidity are also acceptable.

• The Korean Journal of Nuclear Medicine
• /
• v.32 no.2
• /
• pp.121-128
• /
• 1998

Purpose: $Na^+-K^+$ ATPase activity has been estimated by the degree of inhibition of cation transport by cardiac glycosides (ouabain) using Rb-86 as a substrate. The biological characteristisc of T1-201 is known to be similar to those of potassium as a transport substrate in the presence of glucose, insulin or phobol myristate acetate (PMA). The purpose of this study was to measure ouabain sensitive $Na^+-K^+$ ATPase activity using T1-201 and compare with that using Rb-86. Materials and Methods: Smooth muscle cells isolated from rat aorta or human placental umbilical artery were cultured, and used to measure cellular $Na^+-K^+$ ATPase activity. $Na^+-K^+$ ATPase activity was measured as a percentage decrease in cellular uptake of T1-201 or Rb-86 by ouabain under the presence of glucose, insulin or PMA in media. Results: $Na^+-K^+$ ATPase activity measured with T1-201, as a transport substrate, was not different from those measured with Rb-86 in rat or human smooth muscle cell preparation. Incubation with high concentration glucose resulted in about 30% decrease in enzyme activity. In contrast, insulin or PMA resulted in 10-70% or 28% increases from baseline activity, respectively. Conclusion: These results suggests that 71-201 could replace Rb-86 in measurement of ouabain sensitive $Na^+-K^+$ ATPase activity in vitro. High level of glucose concentration decreased cellular $Na^+-K^+$ ATPase activity, but insulin or PMA increased it.

• Journal of Chest Surgery
• /
• v.41 no.2
• /
• pp.229-238
• /
• 2008

Background: Protection of the brain is a major concern during thoracic aortic surgery using hypothermic circulatory arrest (HCA). This study compares the surgical outcomes of two different cerebral protection methods in thoracic aortic surgery using HCA: retrograde cerebral protection (RCP) and antegrade cerebral protection (ACP). Material and Method: We retrospectively reviewed data on 146 patients who underwent thoracic aortic surgery from May 1995 to February 2007 using either RCP (114 patients, Group 1) or ACP (32 patients, Group 2) during HCA. There were 104 dissections (94 acute and 10 chronic) and 42 aneurysms (41 true aneurysms and 1 pseudoaneurysm), and all patients underwent ascending aortic replacement. There were 33 cases of hemiarch replacement, 5 of partial arch replacement, and 21 of total arch replacement. Result: The two groups were similar in preoperative and operative characteristics, but Group 2 had more elderly (over 70 years old) patients (34.4% vs. 10.5%), more coronary artery diseases (18.8% vs. 4.4%), more total arch replacements (46.9% vs. 5.3%) and longer HCA time ($50{\pm}24$ minutes vs. $32{\pm}17$ minutes) than Group 1. The operative mortality was 4.4% (5/114) and 3.1% (1/32), the incidence of permanent neurologic deficits was 5.3% (6/114) and 3.1% (1/32), and the incidence of temporary neurologic deficits was 1.8% (2/114) and 9.4% (3/32) in Groups 1 and 2, respectively. There were no statistical differences between the two groups in operative mortality, postoperative bleeding, or neurologic deficits (permanent and temporary). Conclusion: The early outcomes of aortic surgery using HCA were favorable and showed no statistical difference between RCP and ACP. However, the ACP patients endured longer HCA times and more extended arch surgeries. ACP is the preferred brain protection technique when longer HCA time is expected or extended arch replacement is needed.

• Investigative Magnetic Resonance Imaging
• /
• v.2 no.1
• /
• pp.96-103
• /
• 1998

Purpose : To assess the clinical utility of turbo contrast-enhanced magnetic resonance angiography(CE MRA) in the evaluation of the aortic arch and its major branches and to compare the image quality of CE MRA among different coils used. Materials and Methods : Turbo three-phase dynamic CE MRA encompassing aortic arch and its major branches was prospectively performed after manual bolus IV injection of contrast material in 29 patients with suspected cerebrovascular diseases at 1.0T MR unit. the raw data were obtained with 3-D FISH sequence (TR 5.4ms, TE 2.3ms, flip angle 30, slab thickness 80nm, effective slice thickness 4.0mm, matrix size $100{\times}256$, FOV 280mm). Total data acquisition time was 4. to 60 seconds. We subjectively evaluated the imge quality with three-rating scheme : "good" for unequivocal normal finding, "fair" for relatively satisfactory quality to diagnose 'normal' despite intravascular low signal, and "poor" for equivocal diagnosis or non-visualization of the origin or segment of the vessels due to low signal or artifacts which needs catheter angiography. At the level of the carotid bifurcation, it was compared with conventional 2D-TOF MRA image. Overall image quality was also compared visually and quantitatively by measuring signal-to-noise ratios (SNRs) of the ascending aorta, the innominate artery and both common carotid arteries among the three different coils used(CP body array(n=12), CP neck array(n=9), and head-and-neck(n=8). Results : Demonstration of the aortic arch and its major branches was rated as "good" in 55% (16/29) and "fair" in 34%(10/29). At the level of the carotid bifurcation, image quality of turbo CE MRA was same as or better than conventional 2D-TOF MRA in 65% (17/26). Overall image quality and SNR were significantlygreater with CP body array coil than with CP neck array or head-and-neck coil. Conclusions : Turbo CE MRA can be used as a screening exam in the evaluation of the major branches of the aortic arch from their origin to the skull base. Overall imagequality appears to be better with CP body array coil than with CP neck array coil or head-and-neck coil.

• Journal of Chest Surgery
• /
• v.35 no.6
• /
• pp.430-438
• /
• 2002

It is known that low birth weight is a risk factor for poor outcome in cardiac surgery for many cardiac defects. We reviewed our recent surgical experiences on congenital heart defect (other than patent ductus arteriosus) in low birth weight babies. Material and Method: From September 1994 to February 2001, 31 consecutive infants weighing 2500 g or less underwent cardiac surgery with (OHS group n=12) or without cardiopulmonary bypass (CHS group n=19). A retrospective study was carried out to evaluate short-and intermediate-term outcome. Mean gestational age and age at operation were 36.9 weeks(range, 32.3-42weeks) and 32.1days (range, 0-87days) respectively. Mean body weight at birth and operation were 1972g (range, 1100-2500g) and 2105g (range, 1450-2500 g) respectively. There was no difference between the two groups in age and body weight. Defects included ventricular septal defect (VSD) (n=3), VSD with arch anomaly (n=2), total anomalous pulmonary venous return (n=2), transposition of the great arteries (TGA) (n=2), truncus arteriosus (n=2), and univentricular heart with cor triatriatum (n=1) in OHS group, and coarctation of aorta (n=7), tetralogy of Fallot (TOF) (n=3), TOF with pulmonary atresia (n=3), multiple muscular VSDs (n=1), double outlet right ventricle (n=1), pulmonary atresia with intact ventricular septum (n=2), tricuspid atresia (n=1), and TGA with multiple VSD (n=1) in CHS group. 13 patients (41.9%) were intubated pre-operatively. Result: There were 4 early deaths(＜30 days); 1 (8.3%) in OHS group and 3 (15.8%) in non-OHS group. All these early deaths were related to the pulmonary artery banding(PAB). There was no operative mortality in infants undergoing complete repair and palliative operations other than PAB. Delayed sternal closure was required in 3 patients. Prolonged postoperative mechanical ventilation (>7 days) was required in 7 patients(58.3%) in OHS and 7(38.8%) in CHS group. Late mortality occurred in 3 patients, two of which were non-cardiac. A patient in OHS group was documented to have neurologic sequelae. All the survivors except two are in NYHA class 1. Conclusion: Complete repair and palliative operations other than PAB can be performed in low birth weight infants with low operative mortality and an acceptable intermediate-term result. However, about a half of the patients required long-term postoperative mechanical ventilation.

• Journal of Chest Surgery
• /
• v.34 no.10
• /
• pp.754-762
• /
• 2001

Background: To evaluate the efficacy of arterial switch operation for transposition of great arteries, serial echocardiographic studies were performed in 8 patients who underwent the surgery between 1989 and 1998 at Dept. of Thoracic & Cardiovascular Surgery, Yeungnam University Hospital in Daegu City, Korea. Material and Method: Follow-up period ranged from 6 months to 11 years(average of 4.1 years). Body weight ranged from 2.6kg to 4.8kg, with average of 3.6kg. 5 of 8 patients were preoperatively diagnosed as TGA+VSD, and 3 as TGA+IVS. LV function was evaluated by the measurement of LV shortening fraction, LVSTI, and LVEF. RVSTI was also measured. Postoperative function of valve and growth of great vessels were analyzed by the measurement of PSPGV, valvular regurgitation, LA/AO ratio, root dimension of aorta and pulmonary artery, comparing with the age matched controls, respectively. Result: LVEF had an average of 65.0+9.03% which is tended to increase serially. LVAOPG had an average of 15.9mmHg. RVPAPG, 27.5mmHg. From the measurement of aortic root dimension of 6 patients at end-systole, aortic root growth was assumed to increase more than the mean value of normal growth. PA root dimension at end-systole showed a similar growth progress when compared with age matched normal controls. Postoperative pulmonic valve regurgitation was noted in 5 of total 8 patients, in which 1 patient who showed grade 2 and 4 showed below grade 1. AR, in 6 patients and all grade 1 Except 1 patient, all the valvular regurgitations were below grade 1, which was presumed to be clinically insignificant.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.2 no.1
• /
• pp.65-73
• /
• 1999

Purpose: Regurgitation, vomiting and feeding intolerance are frequent in the neonates. Esophageal function and gastric peristalsis are not fully developed in the neonates, so we should give attention to reduce the incidence of regurgitation and vomiting after feeding. It is necessary to shorten the gastric emptying by change of feeding types and postprandial postures. Gastric emptying time was measured by ultrasound in the neonates to evaluate the effect of feeding types and postprandial postures. Method: We measured gastric antral cross sectional area along the abdominal aorta at the level of the superior mesenteric artery in longitudinal section at NPO state (4 hours after feeding), 0 and every 30 min. after feeding until the value goes below or back to the NPO state. Fifteen neonates were examined in each breast-fed and formula-fed group in supine position. Eighteen and 15 neonates were examined in supine and prone posture after formula feeding, respectively. We used 5 MHz convex prove with Aloka Echo Camera SSD-650. Result: 1) Gastric emptying time of breast-fed infants was $76.0{\pm}20.02$ min. which was significantly shorter than $96.0{\pm}20.28$ min. of formula-fed infants. 2) Gastric emptying time on postprandial prone posture was $85.0{\pm}22.43$ min. which was not significantly different from $96.0{\pm}20.28$ min. on postprandial supine posture. Conclusion: Breast feeding is strongly recommended to the neonates to shorten gastric emptying time. So we can expect to reduce the incidence of regurgitation, vomiting and feeding intolerance. The postprandial posture depends on the traditional trend which is safe and comfortable to the mothers.