[Extracardiac fontan procedure in adult: report of a case]

We report a case of a 28-year-old female who underwent an extracardiac Fontan procedure. The subject was diagnosed as an atrioventricular septal defect (Rastelli classification: type C), a double outlet right ventricle, pulmonary artery stenosis, a hypoplasty of left ventricle, total anomalous venous return (Darling: Ib + IIb), and atrial flutter. She underwent a Blalock shunt and an aorto-pulmonary shunt at the ages of 3 and 9 years, respectively. Under a total CPB, an extracardiac total cavo-pulmonary connection (TCPC), using a 26 mm Hemashield graft, was completed. The postoperative course was uneventful. The complicated atrial anatomy and atrial arrhythmia indicated TCPC in this adult patient.

[A case report of ross operation and ventricular septal defect closure following correction of type A interruption by modified Blalock-Park, pulmonary artery banding and patent ductus arteriosus division]

A 2-year-old boy who had undergone a correction of a type A interruption using a modified Blalock-Park operation, pulmonary artery banding and the division of a patent ductus arteriosus, underwent a Ross operation and closure of ventricular septal defect (VSD). Although a pre-operative echo cardiogram revealed a bicuspid aortic valve, and a Doppler echocardiogram showed only 10 mmHg of pressure gradient across the aortic valve, Ross procedure was performed as a procedure accompanying the closure of a total conus VSD. The total conus VSD was closed with a Dacron patch using pledget mattress sutures. In addition, a running suture was applied over the denuded aortic root and the cranial margin to achieve water tight closure. An aortic root replacement procedure was our first choice for the Ross operation. After both coronary buttons were re-implanted into pulmonary sinuses, a pulmonary artery autograft was wrapped around by the remaining aortic wall for reinforcement to prevent future dilatation. The main pulmonary artery was reconstructed using a bicuspid pericardial valve conduit with a diameter of 24 mm. A post-operative echocardiogram showed no neoaortic valve regurgitation, good coaptation of tri-leaflets, mild regurgitation of pericardial valve and good cardiac performance.

[A modified Fontan operation in the presence of a supracardiac total anomalous pulmonary venous connection]

We report a case of 2-year-old girl with asplenia syndrome who successfully underwent modified Fontan procedure and concomitant repair of supracardiac total anomalous pulmonary venous connection (TAPVC). The preoperative diagnosis included a common atrioventricular canal (type C), a double outlet right ventricle, a common atrium, common atrioventricular valve regurgitation, pulmonary stenosis, and a bilateral superior vena cava (SVC). Cardiac catheterization revealed a Qp/Qs of 1.3, mean PA pressure of 16 mmHg and an Rp of 1.3. The TAPVC drained to left SVC (LSVC) at a position proximal to the hemiazygos vein with an ostium of 5 mm in diameter. The LSVC was divided distal to its connection to the common pulmonary vein (CPV). The TAPVC ostium was cut back into the CPV, then it was anastmosed with posterior aspect of the atrial wall in an effort to provide a wide anastomosis. The postoperative course was uneventful and the patient was discharged from hospital on the 35th postoperative day.

Double-Switch operation for congenitally corrected transposition

Double-switch operation was performed in 76 patients with congenitally corrected transposition of the great arteries at the Heart Institute of Japan, Tokyo Women's Medical University. Detailed surgical techniques of Mustard and Senning procedures for inlet switch, as well as arterial switch operation, pulmonary reconstruction by direct right ventricular-pulmonary arterial anastomosis, and external conduit repair for outlet switch are described in detail.

Optical imaging of excitation propagation evoked by stimulation to the trigeminal caudalis

The present study reports on a characteristic spatio-temporal propagation of differential fluorescent images in the rat brain stem slice by a high-speed optical imaging technique. Coronal or sagittal slices were stained with a voltage-sensitive dye RH-414, and the superficial layer of the trigeminal caudalis (Vc) was then electrically stimulated. The marginal layer and substantia gelatinosa showed larger rostrocaudal excitation than coronal, despite a lack of tract stimulation expansion in either direction. A perfusion of 0.5 micromol/l TTX, not 10 micromol/l CNQX suppressed these propagations. These findings suggest that the superficial layer of Vc has spatial differences in neuronal excitation propagation, as evidenced by morphological observations that dendrites in the superficial layers extend in the rostrocaudal direction.

[A comparison between midline and paramedian approaches for combined spinal-epidural anesthesia]

We compared midline approach with paramedian approach for combined spinal-epidural anesthesia (CSEA) by needle through needle technique. Seventy patients undergoing elective gynecological surgery received CSEA with a 27 G Whitacre spinal needle, which protrudes 12 mm beyond the tip of the Tuohy needle. The successful subarachnoid puncture with first attempt was noted in 33 patients (94%) of midline group (M group), in 31 patients (89%) of paramedian group (P group). At the subarachnoid puncture, skin to epidural space distance (43.2 mm vs 53.4 mm) and protrusion length of spinal needle (5.5 mm vs 8 mm) were significantly longer in the P group than in the M group. Abdominal radiography revealed the flexion of epidural catheter in 19 patients (54%) of M group and in 2 patients (6%) of P group. The choice of midline or paramedian approach for CSEA did not affect the success rate of the subarachnoid puncture, but paramedian approach required longer protrusion length of the spinal needle than midline approach. To raise the success rate of subarachnoid puncture by paramedian approach, a long protruded spinal needle is recommended.

Central mu opioid receptor mechanisms modulate mustard oil-evoked jaw muscle activity

The injection of the small-fibre excitant and inflammatory irritant mustard oil (MO) into the temporomandibular joint (TMJ) region of rats evokes a sustained and reversible increase in electromyographic (EMG) activity of jaw muscles. The 'rekindling' of this nociceptive reflex by intrathecal (i.t.) administration of the opiate antagonist naloxone and mu but not delta and kappa selective opioid antagonist, suggests that it may be modulated by endogenous opioid inhibitory mechanisms.

[Case report of CABG for progressive coronary artery stenosis after 22-year history of Kawasaki disease]

More than 30 years has passed since Kawasaki disease was recognized as an independent disease entity, but the cardiovascular complications of Kawasaki disease are still not well known. We report an 22-year-old woman who underwent triple coronary artery bypass grafting because of a coronary artery aneurysm and multiple coronary artery stenoses, 22 years after the diagnosis of Kawasaki disease. A 2 cm coronary artery aneurysm due to Kawasaki disease was diagnosed when she was 10 years old, when she first presented with the symptom of dyspnea on effort. Since then, she was followed at the outpatient clinic. When she was 19 years old, the first coronary catheterization was performed. Two years later, the second coronary catheterization revealed progression of coronary artery disease. Therefore, coronary artery bypass grafting was performed. This case is rare from the point of view of long-term progression of coronary artery disease.

Angiogenesis effects of nerve growth factor (NGF) on rat corneas

This study was performed to evaluate the effects of nerve growth factor (NGF) upon angiogenesis in the rat cornea, to examine its possible application as an alternative angiogenic inducer and to provide basic data for further studies. Angiogenesis was induced by cornea micropocket assay, as previously described. Eight of thirty two eyes of Sprague-Dawley rats were randomly assigned to one of four groups, namely, a non-NGF group (Group 0), a 0.5 ng of NGF group (Group 0.5), a 1.0 ng of NGF group (Group 1.0) and a 5.0 ng of NGF group (Group 5.0). Pellets made of poly-2-hydroxylethylmethacrylate and sucralfate were implanted into the corneal stroma no closer than 1 mm from the limbus. After the implantation, the number of new vessels, vessel length and circumferential neovascularization were examined daily under the surgical microscope over a period of 7 days. The area of neovascularization was determined using a mathematical formula. Although new vessels in Group 0 and Group 0.5 were first observed at day 5, those of Groups 1.0 and 5.0 were first noted on days 4 and 3, respectively. However, the growth rates of new vessels in Groups 1.0 and 5.0 were higher than those of Groups 0 and 0.5 with the passage of time. The number, length, circumferential neovascularization and areas covered by the vessels in Groups 1.0 and 5.0 were significantly more than in Group 0 and Group 0.5 (p<0.05). This study showed that NGF had a dose-dependent angiogenic effects on the rat cornea and that the minimal effective dose of NGF was 1.0 ng per cornea. Also, it showed that NGF would be useful in angiogenic studies as an alternative angiogenic inducer.

Blind separation of cardiac components and extraction of input function from H(2)(15)O dynamic myocardial PET using independent component analysis

The independent component analysis (ICA) method is suggested to be useful for separation of the ventricles and the myocardium and for extraction of the left ventricular input function from the dynamic H(2)(15)O myocardial PET. The ICA-generated input function was validated with the sampling method, and the myocardial blood flow (MBF) calculated with this input function was compared with the microsphere results.

METHODS

We assumed that the elementary activities of the ventricular pools and the myocardium were spatially independent and that the mixture of them composed dynamic PET image frames. The independent components were estimated by recursively minimizing the mutual information (measure of dependence) between the components. The ICA-generated input functions were compared with invasively derived arterial blood samples. Moreover, the regional MBF calculated using the ICA-generated input functions and single-compartment model was correlated with the results obtained from the radiolabeled microspheres.

RESULTS

The ventricles and the myocardium were successfully separated in all cases within a short computation time (<15 s). The ICA-generated input functions displayed shapes similar to those obtained by arterial sampling except that they had a smoother tail than those obtained by sampling, which meant that ICA removed the statistical noise from the time--activity curves. The ICA-generated input function showed a longer time delay of peaks than those obtained by arterial sampling. MBFs estimated using the ICA-generated input functions ranged from 1.10 to approximately 2.52 mL/min/g at rest and from 1.69 to approximately 8.00 mL/min/g after stress and correlated well with those calculated with microspheres (y = 0.45 + 0.98x; r = 0.95, P < 0.000).

CONCLUSION

ICA, a rapid and reliable method for extraction of the pure physiologic components, was a valid and useful method for quantification of the regional MBF using H(2)(15)O PET.

Functional uncoupling of T-cell receptor engagement and Lck activation in anergic human thymic CD4+ T cells

Human thymic CD1a-CD4+ T cells in the final stage of thymic maturation are susceptible to anergy induced by a superantigen, toxic shock syndrome toxin-1 (TSST-1). Thymic CD4+ T-cell blasts, established by stimulating human thymic CD1a-CD4+ T cells with TSST-1 in vitro, produce a low level of interleukin-2 after restimulation with TSST-1, whereas TSST-1-induced adult peripheral blood (APB) CD4+ T-cell blasts produce high levels of interleukin-2. The extent of tyrosine phosphorylation of the T-cell receptor zeta chain induced after restimulation with TSST-1 was 2-4-fold higher in APB CD4+ T-cell blasts than in thymic CD4+ T-cell blasts. The tyrosine kinase activity of Lck was low in both thymic and APB CD4+ T-cell blasts before restimulation with TSST-1. After restimulation, the Lck kinase activity increased in APB CD4+ T-cell blasts but not in thymic CD4+ T-cell blasts. Surprisingly, Lck was highly tyrosine-phosphorylated in both thymic and APB CD4+ T-cell blasts before restimulation with TSST-1. After restimulation, it was markedly dephosphorylated in APB CD4+ T-cell blasts but not in thymic CD4+ T-cell blasts. Lck from APB CD4+ T-cell blasts bound the peptide containing the phosphotyrosine at the negative regulatory site of Lck-505 indicating that the site of dephosphorylation in TSST-1-activated T-cell blasts is Tyr-505. Confocal microscopy demonstrated that colocalization of Lck and CD45 was induced after restimulation with TSST-1 in APB CD4+ T-cell blasts but not in thymic CD4+ T-cell blasts. Further, remarkable accumulation of Lck in the membrane raft was observed in restimulated APB CD4+ T-cell blasts but not in thymic CD4+ T-cell blasts. These data indicate that interaction between Lck and CD45 is suppressed physically in thymic CD4+ T-cell blasts and plays a critical role in sustaining an anergic state.

Effects of leucocyanidines on activities of metabolizing enzymes and antioxidant enzymes

Procyanidolic oligomers (leucocyanidines, LCs) extracted from grape seeds (Vitis vinifera) are known to have antioxidant and antimutagenic activities, and a protective effect against cardiovascular disease. In the present study we examined the influence of LCs on the activities of phase 1 enzymes and conjugation enzymes and on antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase. Administration of LCs (25, 50, and 100 mg/kg. p.o. for 7 d) markedly decreased the activities of NADPH-cytochrome P450 reductase, P4501A1, P4501A2, and P4503A4, but significantly increased the activities of glutathione S-transferase and phenolsulfotransferase in rat liver. However, the activities of antioxidant enzymes were not affected by LC administration. The inhibition of P450s and increases in phase II enzyme activities indicate a role for LCs as a chemopreventive agent against toxic or carcinogenic metabolites of P450 isozymes.

Involvement of GABA(A) receptor in modulation of jaw muscle activity evoked by mustard oil application to the rat temporomandibular joint

The effect of intrathecal administration of the GABA(A) receptor antagonist bicuculline methylbromide on jaw muscle electromyographic (EMG) activity evoked by mustard oil injection into the rat temporomandibular joint was studied. Bicuculline given prior to mustard oil augmented the EMG activity evoked by mustard oil, and "rekindling" of EMG activity was induced by bicuculline given 30 min after mustard oil. These results suggest that central GABA(A) receptors modulate reflex responses to noxious craniofacial stimuli.

Effect of hemofiltrated whole blood pump priming on hemodynamics and respiratory function after the arterial switch operation in neonates

BACKGROUND

Primed blood might have some deleterious effects on neonates during cardiopulmonary bypass (CPB) due to unbalanced electrolytes and inflammatory mediators. We hemofiltrated pump-primed blood before CPB to reduce inflammatory mediators and to adjust pH and the concentrations of electrolytes. The current study investigated the effects of hemofiltrated whole blood priming on hemodynamics and respiratory function after CPB in neonates.

METHODS

Patients who underwent the arterial switch operation in the neonatal period for transposition of the great arteries with intact ventricular septum were chosen for this study. Seventeen patients underwent CPB with hemofiltrated blood priming (group HF) and 23 patients underwent CPB with nonhemofiltrated blood priming (group N). The concentrations of electrolytes and bradykinin and high molecular weight kininogen of the primed blood before and after hemofiltration were measured. At 4 hours after completion of CPB, the left ventricular percent fractional shortening, and the relation between the mean velocity of shortening and the end-systolic wall stress (stress velocity index), were measured by echocardiogram in 7 patients in group HF and 6 patients in group N. Alveolar--arterial oxygen tension difference (AaDO2) and respiratory index (AaDO2 divided by arterial oxygen tension) were measured at several points for 48 hours after CPB in all patients.

RESULTS

Hemofiltration of the primed blood maintained electrolytes within a physiologic level and significantly reduced the concentrations of bradykinin (5,649 +/- 1,353 pg/mL versus 510 +/- 35 pg/mL, p < 0.05) and high molecular weight kininogen (52.7% +/- 3.2% versus 40.1% +/- 3.0% of normal plasma value, p < 0.05). The percent of fractional shortening at 4 hours after completion of CPB was significantly higher in group HF (n = 7) than in group N (n = 6) (22.0% +/- 0.7% versus 16.0% +/- 0.4%, p < 0.01). There was also a trend toward better stress velocity index in group HF than in group N (0.81 +/- 0.81 versus -2.17 +/- 0.45, p = 0.09). AaDO2 and respiratory index were significantly lower in group HF than in group N for 48 hours after CPB, respectively (p < 0.05).

CONCLUSIONS

Hemofiltrated fresh whole blood used for CPB priming attenuated cardiac impairment at early reperfusion periods and reduced pulmonary dysfunction in neonates with transposition of the great arteries with intact ventricular septum. This therapeutic strategy may have an advantage in preventing lung and heart dysfunction in pediatric patients who need CPB priming with blood.

Definite improvement in left ventricular function at six years after the Takeuchi procedure

We report a case of a six-year-old girl who underwent the Takeuchi procedure for anomalous origin of the left coronary artery from the pulmonary artery at the age of 4 months. The left ventricular function was severely deteriorated before the initial operation and at 6 years after the procedure showed a remarkable improvement. Mitral regurgitation disappeared during the 6 years. The intrapulmonary tunnel was sufficiently patent to provide adequate blood flow for the anomalous coronary artery. This patient showed supravalvular stenosis due to shrinkage and thickening in the equine pericardium used for reconstruction of the pulmonary artery, and this stenosis was successfully released by autologous pericardial patch angioplasty.

[Heparin monitoring during cardiopulmonary bypass in congenital heart surgery]

The Hepcon/HMS system automatically provides the activated clotting time and a whole blood heparin concentration. It also provides the adequate protamine dose by titration of protamine to heparin. 45 patients undergoing congenital heart surgery with cardiopulmonary bypass (CPB) were studied by the Hepcon/HMS device. We measured the heparin dose response before heparin administration, and the ration between the dose of protamine (ml) which was necessary for heparin neutralization at the termination of CPB and the dose of total heparin (ml) in each patient. The value of heparin dose response ranged 120-390 (mean 228) IU/kg. The ratio between protamine dose and heparin dose varied 0.11-0.99 (mean 0.55). There was a statistically significant correlation between the duration of CPB and this ratio (r = -0.51, n = 45, p = 0.0005). From the standpoint of variances in the value of heparin dose response, conventional way of the heparin administration according to the patient's body weight alone may cause inadequacy of anticoagulation during CPB. A dose of protamine determined by Hepcon device that is smaller than a conventional dose of protamine prevents inadvertent overdose and, therefore, can reduce the adverse effects excessive protamine has.

[Cerebral oxygenation during non-blood prime cardiopulmonary bypass in congenital heart surgery]

To analyze oxygen delivery to the brain and cerebral cellular oxygenation during non-blood prime and blood prime cardiopulmonary bypass (CPB), 22 patients undergoing cardiac surgery with CPB were studied by near infrared spectroscopy (NIRS) monitor (NIRO 500, Hamamatsu Photonics). NIRS can assess continuously cytochrome oxidase (Cyt.aa 3) which is the terminal enzyme of the intramitochondrial respiratory chain. Patients were grouped according to conditions of CPB management: one group underwent repair with non-blood prime (group A, n = 12); the second group underwent with blood prime (group B, n = 10). Body weights ranged from 5.5 kg to 58 kg in group A, and 2.9 kg to 16 kg respectively. CPB was maintained at flow rates between 100 to 150 ml/kg/min. and the acid-base management strategy was alpha stat in all patients. No neurological complication was observed. NIRS date were expressed as changes from baseline where cannulation was prepared. The lowest value of Cyt.aa 3 was -2.7 +/- 0.7 mumol/l in the group A, and -3.9 +/- 1.0 mumol/l in the group B. From the standpoint of changes in Cyt.aa 3, non-blood prime cases we studied were speculated to be within a safety limit. In order to define the definite safety limits, however, further studies including the reduction velocity of Cyt.aa 3 signal as well as the absolute value of the lowest Cyt.aa 3 concentration are required.

Postnatal development of central nociceptive mechanisms modulating jaw muscle activity in the rat

Postnatal changes in the electromyographic (EMG) activity of jaw muscles evoked by mustard oil (MO) application into the rat temporomandibular joint region and the recurrence of increased jaw muscle activities after intravenous injection of naloxone were compared among 4, 6 and 8-week-old rats. In all the groups, MO application increased EMG activity on the ipsilateral side, however, 4-week old rats showed only a small increase in EMG activity on the contralateral side. The EMG activity on the contralateral side increased in an age-dependent manner. The recurrence of increased jaw muscle activity was not induced in 4-week old rats. These results suggest that a neural circuit for generating contralateral responses and mechanisms for central excitation are not established until after 4 weeks postnatally.

[Intra- and postoperative heart rate changes following propofol anesthesia; a comparison with isoflurane anesthesia]

Bradycardia during propofol anesthesia is well known, but bradycardia after propofol anesthesia has not been studied well. We compared perioperative heart rates in patients who had undergone gynecological surgery under lumbar epidural anesthesia supplemented with light general anesthesia using isoflurane and nitrous oxide in oxygen (Group Iso, n = 25) with those who had received lumbar epidural anesthesia supplemented with propofol (Group Prop, n = 25). The heart rates for the Group Prop were significantly lower (P < 0.05) than those for the Group Iso after the induction of anesthesia up to 2 hours after surgery. Two patients in the Group Prop developed bradycardia below 50 bpm 1 and 2 hours after surgery. In one of them intravenous atropine was necessary to treat bradycardia. We conclude that more attention should be paid to postoperative as well as intraoperative bradycardia in patients who receive propofol.

[Pulmonary outflow tract reconstruction with autologous tissue during the Ross procedure: right ventricular characteristics in mid-term follow-up]

BACKGROUND

The Ross procedure requires the interposition of prosthetic or homograft extracardiac conduits to establish ventricle-pulmonary artery connection (RV-PA). These materials usually require multiple reoperations because of conduit failure. To avoid the re-replacement of currently available conduits, usage of autologous tissue may be preferable to reconstruct RV-PA connection during the Ross procedure, especially in the pediatric age group.

METHOD

Ten patients (mean age 8.7 years, range 2-23) with congenital aortic valve disease underwent the Ross procedure between June, 1996 and July, 1998. To establish RV-PA continuity, autologous aortic wall including aortic valve with a gusset of pericardial tissue was used in six patients, rolled pericardial conduit with fresh pericardial bicuspid valve in three and one direct anastomosis of pulmonary posterior wall onto the right ventricle with a fresh pericardial monocusp valved patch. All patient's postoperative courses were uneventful. All patients were followed up (mean follow-up period: 21.6 +/- 6.6 months) and postoperative right ventricular characteristics, cardio-thoracic ratio (CTR) on chest X-ray and pulmonary valve function were evaluated.

RESULTS

Postoperative right ventricular end-diastolic volume, right ventricular ejection fraction and right ventricular end-diastolic pressure did not change significantly (RVEDV: 128 to 113% of normal, RVEF: 56.4 to 51.5%, RVEDP: 5.9 to 10.1 mmHg). Pulmonary regurgitation during follow-up was mild in six patients and moderate in four. However, CTR decreased significantly over time (preop.: 56.5% postop.: 58.5%, late period: 53.4%).

CONCLUSION

Our results support the concept of the reconstruction of pulmonary outflow tract without foreign materials during the Ross procedure. Longer follow-up are necessary to define the possible limitation of this technique.

Sevoflurane and isoflurane reduce oxygen saturation in infants

Volatile anesthetics are generally known to exert several influences on the respiratory system, but their direct effect on oxygen saturation as measured by pulse oximetry (SpO2) in infants remains unknown. In this study, 70 infants under 2 years of age who received general anesthesia were examined to determine the effects of several volatile anesthetics and nitrous oxide on SpO2. After endotracheal intubation, the subjects were ventilated using a Jackson-Rees circuit with oxygen, nitrous oxide, and either sevoflurane, enflurane, or isoflurane adjusted to twice the adult minimum alveolar concentration (MAC) for the agents when used in combination with 67% nitrous oxide. In all cases, the end-tidal carbon dioxide tension (PetCO2) was maintained within the same range (28-35 mm Hg). Significantly lower SpO2 values (paired t test, P < .05) were observed when the subjects were ventilated with oxygen, 67% nitrous oxide, and sevoflurane or isoflurane--but not with oxygen, 67% nitrous oxide, and enflurane--than when they were administered oxygen, 50% nitrous oxide, and the original concentration of each volatile anesthetic. These results suggest that sevoflurane and isoflurane have different effects from enflurane on gas exchange systems.

Alteration of cell wall composition leads to amphotericin B resistance in Aspergillus flavus

An amphotericin B (AmB)-resistant mutant was isolated from a wild-type AmB-susceptible strain of Aspergillus flavus by serial transfer of conidia on agar plates containing stepwise increased concentrations of AmB up to 100 microg ml-1. The acquired resistance of mycelia was specific for polyene-antibiotics AmB, nystatin and trichomycin. Spheroplasts derived from the resistant mycelia were as susceptible to AmB as the wild-type. Chemical analysis of the cell wall revealed that levels of alkali-soluble and -insoluble glucans were significantly higher in the resistant mycelia as compared to those in the wild-type. When resistant mycelia were treated with SDS, they adsorbed as much AmB as wild-type mycelia. These results suggest that alterations in the cell wall components of mycelia, especially 1,3-alpha-glucan and protein complex in the outermost wall layer, lead to AmB resistance in A. flavus.

Time course of endothelin-1 and adrenomedullin after the Fontan procedure

BACKGROUND

The endothelium-derived vasoconstrictor endothelin (ET)-1 might contribute to the physiology of blood flow regulation and play a role in cardiovascular disease. Adrenomedullin (AM) is a potent vasodilator peptide that has major effects on cardiovascular function and has multiple biologic effects involved in cardiovascular homeostasis. Although pulmonary vascular resistance is known to be one of the most important factors to determine the indications for a Fontan procedure, the time course of the plasma cytokine before and after the Fontan procedure is not known.

METHODS

Sixteen patients were divided into two groups, 8 patients (1 to 14 years) who had the Fontan procedure (atriopulmonary connection) and 8 age-matched controls who had biventricular repair with normal central venous pressure. Plasma ET-1 and adrenomedullin levels were measured in both groups immediately before cardiopulmonary bypass, immediately after cardiopulmonary bypass, and 6 and 24 hours after cardiopulmonary bypass. A thermodilution catheter was inserted during the operation, and mean pulmonary arterial pressure, pulmonary wedge pressure, and cardiac output were measured, and pulmonary vascular resistance was calculated at the same time points. Correlation between the plasma ET-1 levels and pulmonary vascular resistance data were obtained in the Fontan group.

RESULTS

Plasma ET-1 levels in the Fontan group were elevated after operation and were higher than the control group at 6 and 24 hours after cardiopulmonary bypass. Plasma adrenomedullin in the Fontan group was lower than in the control group at 6 and 24 hours after cardiopulmonary bypass. A significant positive correlation was obtained between the plasma ET-1 and pulmonary vascular resistance data (r = 0.475).

CONCLUSIONS

Imbalance between increased ET-1 and relatively decreased adrenomedullin after cardiopulmonary bypass in the Fontan procedure could contribute to dominant effects of ET-1, which might induce vasoconstriction after the Fontan procedure. ET-1 might play an important role in maintaining vasoconstriction after the Fontan procedure.

[A case of supravalvular mitral ring]

A two-year-old girl with supravalvular mitral ring successfully underwent the excision of the ring. The preoperative echocardiogram showed supravalvular mitral ring and almost normal mitral leaflets. We paid attention not to injury mitral valve at the excision of the ring because supravalvular mitral ring adhered to the mitral valve.

[A case of Bentall's operation for an 11-year-old patient with Marfan syndrome]

An 11-year-old girl who was diagnosed to have Marfan syndrome in her infancy, visited us with complaints of easy fatigability and chest discomfort. She was pointed out to have acute development of annuloaortic ectasia with severe aortic regurgitation and mild mitral regurgitation. She underwent replacement of the ascending aorta and aortic valve using composite graft with prosthetic valve (Bentall's operation) and circular annuloplasty of the mitral valve. Bentall's operation for infants and children is remarkably rare because in this generation, acute development of aortic dilatation leading rupture and dissection is quite infrequent while main death is caused by mitral regurgitation.