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We report an angle-resolved photoemission spectroscopy (ARPES) study of ${\mathrm{Li}}_{x}{\mathrm{CoO}}_{2}$ single crystals which have a hole-doped ${\mathrm{CoO}}_{2}$ triangular lattice. Similar to ${\mathrm{Na}}_{x}{\mathrm{CoO}}_{2}$, the Co $3d\phantom{\rule{4pt}{0ex}}{a}_{1g}$ band crosses the Fermi level with strongly renormalized band dispersion while the Co $3d\phantom{\rule{4pt}{0ex}}{e}_{g}^{\ensuremath{'}}$ bands are fully occupied in ${\mathrm{Li}}_{x}{\mathrm{CoO}}_{2}$ ($x=0.46$ and 0.71). At $x=0.46$, the Fermi surface area is consistent with the bulk hole concentration indicating that the ARPES result represents the bulk electronic structure. On the other hand, at $x=0.71$, the Fermi surface area is larger than the expectation which can be associated with the inhomogeneous distribution of Li reported in the previous scanning tunneling microscopy study by Iwaya et al. [Phys. Rev. Lett. 111, 126104 (2013)]. However, the Co $3d$ peak is systematically shifted towards the Fermi level with hole doping excluding phase separation between hole rich and hole poor regions in the bulk. Therefore, the deviation of the Fermi surface area at $x=0.71$ can be attributed to hole redistribution at the surface avoiding polar catastrophe. The bulk Fermi surface of Co $3d\phantom{\rule{4pt}{0ex}}{a}_{1g}$ is very robust around $x=0.5$ even in the topmost ${\mathrm{CoO}}_{2}$ layer due to the absence of the polar catastrophe.

We examined the arrangement of the coronary arterial and cardiac venous systems in 46 specimens with discordant atrioventricular connections so as to identify any structural abnormalities and to consider their surgical implications in terms of anatomical biventricular repair. Grossly abnormal arterial courses were seen in 11 hearts (24%). A substantial branch supplying the morphologically right ventricular outflow tract, which could restrict a ventriculotomy, was found in 61% of cases. The coronary sinus received all the morphologically right ventricular veins, as well as the posterior interventricular vein, in 40 hearts, this pattern being in contrast to the pattern in the normal heart. The morphologically left ventricular and anterior interventricular veins, all of which drain via the coronary sinus in the normal heart, were frequently connected independently to the morphologically right atrium in the specimens with discordant connections, the drainage occurring through the spaces between the pectinate muscles. These direct drainages are at risk of potential damage either by extensive intra-atrial maneuvers or by postoperative intraatrial thrombosis. It is predicted, therefore, that surgical results can be improved still further when account is taken of this vascular anatomy of the heart itself.

The conducting films were prepared from a solution containing a soluble poly(4-methylpyrrole 3-carboxylate) and an organic electron acceptor. The principal acceptor studied here was tetracyanoethylene (TCNE). The solution was homogeneous, so that the conducting film was obtained directly from the solution cast on a glass plate or some substrates. The present films exhibited relatively high conductivity (≈ 10 4 ∼ 10 1 S/cm), which was dependent on quantity of TCNE added to the polymer solution and the alkyl-chain length of the esters.

The purpose of this study is to analyze the operative maneuver and long term outcome of the arterial switch operation (ASO) for congenitally corrected transposition of the great arteries (c-TGA) or double inlet left ventricle (DILV). Since October 1977, 221 patients had undergone ASO in National Cardiovascular Center, Japan. Of these, 8 patients underwent ASO as a part of double switch operation (DSO) for c-TGA, and 1 patient underwent ASO and ventricular septation for the DILV with a rudimentary right ventricle simultaneously. We retrospectively reviewed these 9 patients. Six patients had a past history of the pulmonary artery banding. Age at the time of ASO ranged from 6 months to 5 years (median 3 year). As a reconstruction of the pulmonary artery at the time of ASO, Lecompte maneuver was performed in 7 patients, and original Jatene procedure was performed in 2. Coronary transfer was done as usual in all patients. There was no early death, and 1 patient died 1 year after the operation due to chronic heart failure. Late complication related to the ASO was pulmonary artery stenosis (1 patient after DSO) and aortic regurgitation (1 patient after ventricular septation).

Aneurysmal dilatation can occur infrequently at the proximal site of an arteriovenous fistula probably because of abnormal wall stresses. However, there might be other intrinsic factors that contribute to aneurysmal formation besides the fistula, because only a very small number of patients with fistulae develop such an aneurysm. We describe herein the histopathological characteristics of a brachial artery aneurysm in a 57-year-old male patient on cholesterol apheresis through a radio-cephalic fistula, and the relationship of the aneurysm with the underlying disease is discussed.

The infection of an endoluminal stent graft (ESG) for AAA repair is unusual. We report the successful management of this serious complication with an open in situ graft replacement and omentopexy.

To promote further improvement of surgical results in the longer terms after the Fontan procedure, we have paid attention to age at operation. Establishment of a non-cyanotic circulation at younger stage, for example around 1 year of age, could have potential advantages in postoperative cardiac performance and functional status. In order to commence the Fontan circulation safe and sound, in turn, the surgical intervention ought to be arranged in a less invasive fashion. In this respect, we introduced off-pump Fontan procedure. Since April 1996, 77 patients have undergone the off-pump Fontan procedure. Its less invasive nature was demonstrated in terms of inflammatory reaction immediately after the operation. Further devices are being sought. These include an alternative off-pump procedure even without a temporary bypass for drainage through the inferior caval vein, which has been thus far applied in 14 patients. This option proved to provide readily an excellent surgical field when an extracardiac conduit is to be anastomosed to the orifice of the inferior caval vein. Another device can be a cordial preparation of the extracardiac channel at the time of the bidirectional Glenn procedure when the staged approach is chosen.

In patients with Marfan syndrome, pregnancy is associated with a potential higher risk of aortic dissection. To determine the incidence and characteristics of aortic dissection in pregnancy, clinical courses of 8 patients with Marfan syndrome were reviewed. Aortic dissection occurred in 3 patients, one of whom had developed rapid dilatation of the ascending aorta during pregnancy. The patient underwent Bentall operation subsequent to cesarean section and simple hysterectomy. All patients tolerated pregnancy well, with favorable maternal and fetal outcomes. Follow-up echocardiography showed no apparent worsening of cardiovascular status attributable to pregnancy such as aortic dilatation and aortic regurgitation except for one patient. Dilatation of the ascending aorta during pregnancy is considered to be an important predictor for aortic dissection. Close observation should be mandatory in such patients. In patients with serious cardiovascular involvement such as acute aortic dissection, cesarean section is preferable for delivery. To prevent hemorrhagic complications under systemic heparinization, simultaneous hysterectomy should be considered as one option.

The outcome of aortic valve-sparing root reconstruction in Marfan syndrome was reviewed. Thirteen patients with Marfan syndrome underwent aortic valve-sparing root reconstruction for annuloaortic ectasia or aortic root dissection between 1994 and 1999. The grade of preoperative aortic regurgitation was I in 4, II in 2, III in 5, IV in 2 patients. The procedures of aortic valve-sparing were reimplantation in 7 and remodeling in 5 patients. There was no hospital and late death. Recurrence of aortic regurgitation greater than moderate grade developed in 1 patient immediately after the surgery and in the other 4 patients in the late stage. One patient of them required aortic valve replacement for it. Aortic valve-sparing root reconstruction is applicable in Marfan patients, although the indication should be cautious. Close observation is needed for recurrence of aortic regurgitation.

Recent modification of the Fontan operation was followed by remarkable improvement of surgical results in patients with tricuspid atresia and univentricular heart. Application of TCPC-type procedures contributed to this progress and new developments will yield better long-term postoperative results. Surgical strategies with the Fontan operation should include various preparatory procedures, such as systemic-pulmonary shunt, pulmonary arterial banding, plasty or reconstruction of pulmonary arteries, bidirectional Glenn anastomosis, creation of additional aortopulmonary anastomosis, and coil embolization of aortopulmonary collateral arteries.

Since 1992, 46 patients have undergone the Ross procedure. Of these, a pulmonary homograft was used for reconstruction of the RVOT in 16, and a tailored heterologous or autologous pericardial roll tube in 9. In the remaining 21, the autologous tissues were used as a posterior wall of the channel, placing another patch (bearing a monocusp in 14) anteriorly. All the patients survived the procedure. Reoperation has been needed thus far in one for infection of the prosthetic patch placed at the right ventricular outflow tract, and catheter intervention in 2 for mild obstruction across the channel. On the basis of postoperative catheterization, presence or absence of a valvar structure across the right ventricular outflow tract did not affect ejection fraction of the right ventricle and right atrial pressure. In contrast, right ventricular end diastolic volume was smaller, as well as diastolic pulmonary arterial pressure was higher, when a competent trifoliate valve was provided at the right ventricular outflow tract. An incision to the ventricular septum for subaortic stenosis, coronary arterial obstruction preoperatively present, and age at operation younger than 2 years old, were unfavourable factors affecting right ventricular performance. We conclude that, in the majority of our patients, right ventricular performance was unlikely impaired even without a competent pulmonary valve. Use of a homograft, however, could be preferred in a selected group of patients with deleterious circumstances on the postoperative circulation.

Major advances have been achieved in surgery during the past century and further dynamic changes are expected along with progress in immunology, tissue and mechanical engineering, etc. in the 21st century. However, fewer medical students will choose the surgical field as their specialty, primarily due to the long training period, and inadequate income as compared to the heavy workload. To recruit the best and the brightest students in surgery, early exposure to the positive aspects of the surgical field is desirable. The training system should be further refined, and a sufficient number of positions with appropriate remuneration must be mode available.

When replacing the regurgitant tricuspid valve in children, the decision to use either a bioprosthesis or a mechanical valve remains controversial.The atrioventricular valve for the pulmonary circulation was replaced in 11 young patients aged between 8 months and 13 years. Complications of congenital cardiac malformation were present in seven patients, and Ebstein's anomaly in three; tricuspid valvular regurgitation was an isolated lesion in one patient. A bioprosthesis was implanted on seven occasions, and a bileaflet mechanical valve on eight, including re-replacement of the valve in four patients.One patient died two years after implantation due to respiratory problems. Tricuspid stenosis due to valve calcification occurred in four bioprostheses at between four and nine years after initial replacement (57%). In three of these cases the native valve leaflets had not been removed. Thrombosis occurred in one patient with a mechanical valve; rereplacement was successful. Anticoagulant-related hemorrhage occurred in another patient. Among patients receiving a mechanical valve, 83% of valves were dysfunction-free after five and ten years.When replacing an atrioventricular valve for the pulmonary circulation in children, we prefer to use a low-profile mechanical valve, especially when extensive repair of intracardiac malformation has been carried out, but ventricular function is good. In children with poor cardiac performance, a bioprosthesis is preferred, with total resection of the native valve leaflets.

Eight patients, 4 males and 4 females ranging in age from 10 to 54 years (mean 27 +/- 13 years) underwent the Ross operation using a cryopreserved pulmonary homograft harvested by and cryopreserved in our institutional "Tissue Bank". Seven patients had a congenital bicuspid aortic valve and 3 patients had had healed infective endocarditis of the aortic valve. Four young female patients wanted to have a baby after operation. The Ross procedure was carried out utilizing aortic root replacement techniques in all patients. All patients survived and are currently in NYHA class 1, but 2 cardiac events occurred in 2 patients during the mean follow-up term of 29 +/- 19 months. The one was the anastomic stenosis between the homograft and distal pulmonary artery treated by balloon dilatation and the other was ventricular tachycardia eventually managed by the insertion of an ICD. Pulmonary autograft valve regurgitation is present in 3 patients, but it is not progressive up to the present time. Pulmonary homograft valves function well in all patients. The Ross operation for adolescents and young adults should become more popular along with more easy availability of homograft valves based upon the establishment of the "Homograft Valve Bank" system in Japan.

Our clinical experience was reviewed to determine the efficacy of replacement of the atrioventricular (AV) valve for the systemic circulation in children with discordant AV connections undergoing functional biventricular repair.Nine children underwent replacement of the morphologically tricuspid valve at the age of 10 months to 15 years. Ventriculoarterial connections were discordant in five children, and double outlet right ventricle with pulmonary stenosis or atresia in four. In all children the prosthesis chosen was a mechanical valve; valve sizes ranged from 19 mm to 31 mm.One patient died of ventricular failure immediately after surgery. Two patients underwent reoperation for re-replacement at eight and 68 months after the initial replacement because of non-structural dysfunction. Complete AV block occurred after intracardiac maneuvers in the non-survivor. Transient AV dissociation was noted in another patient. General conditions improved greatly after surgery in all survivors. In the morphologically right ventricle placed for the systemic circulation the end-diastolic volume fell from 327 +/- 182% (range: 109-621%) to 169 +/- 97% (range: 85-352%) of the anticipated normal value (p = 0.03), while pressure fell from 13 +/- 4 (range: 7-19) mmHg to 8 +/- 3 (range: 2-12) mmHg (p = 0.005). The ejection fraction was only marginally reduced (47 +/- 13% (range: 26-62%) preoperatively versus 34 +/- 11% (range: 20-54%) postoperatively; p = 0.13).In children with discordant atrioventricular connections and severe regurgitation across the morphologically tricuspid valve, the valve can be efficiently replaced for the systemic circulation.

The study aim was to determine whether re-replacement of the systemic atrioventricular (AV) valve can be achieved efficiently in children.The systemic AV valve was re-replaced in 10 children. Initial replacement was needed for regurgitation in nine cases and congenital mitral stenosis in one case at a mean age of 3.7 +/- 3.1 years (range: 0.7-10.2 years). The initial prosthesis chosen was a mechanical valve in all cases; prosthesis size ranged from 16 mm to 27 mm. Reoperation was indicated at a mean age of 9.7 +/- 3.6 years (range: 3.5-14.8 years) because of non-structural dysfunction in five cases, prosthetic valve endocarditis in two, thrombosed valve in two, and progressive obstruction of the left ventricular outflow tract in one case. Fibrous tissues were extensively resected to enlarge the valvular orifice. A translocation maneuver was employed in five cases.Re-replacement using a bileaflet mechanical valve was successful, with no operative or late deaths. Up-sizing was feasible in six cases with the initial valveor = 25 mm, the alternative prosthesis being 2-8 mm (mean 4.5 mm) larger than the initial one. Consecutive echocardiography demonstrated improved peak flow velocity across the AV valve (from 2.3 +/- 0.6 to 1.6 +/- 0.3 m/s). Catheterization showed improved mean pulmonary arterial pressure (from 32 +/- 13 to 21 +/- 3 mmHg). No change was seen in cardiac index (3.4 +/- 0.6 and 3.5 +/- 0.6 l/min/m2) or systemic ventricular ejection fraction (55 +/- 14% and 49 +/- 23%).Re-replacement of the systemic AV valve can be achieved efficiently, even in children, with up-sizing feasible by appropriate surgical maneuvers.

A new technique is described to repair aortopulmonary window with total defect in an 8-day-old baby. Because we expected the future growth of aorta, we used the anterior wall of the pulmonary artery as a large flap to reconstruct the posterolateral aortic wall. An equine pericardial patch was used to repair the defect in the pulmonary artery. This is a logically effective method for aortic reconstruction in a neonate with a large aortopulmonary septal defect.

It is now well recognized that regurgitation through a common atrioventricular valve can compromise the clinical course both before and after surgical interventions in patients with visceral heterotaxy. This may reflect the anatomic structure of the valve. This study aimed to determine whether the structure of the common atrioventricular valve found in the setting of hearts with isomeric atrial appendages and double inlet ventricle differs from that of the valve guarding a common junction in hearts with biventricular atrioventricular connections.Sixty-three autopsied hearts with double inlet ventricle and isomeric atrial appendages were studied, in addition to 79 with isomerism and biventricular atrioventricular connections, all having a common valve guarding the atrioventricular junctions.A valve with three or four leaflets was seen more frequently in hearts with double inlet ventricle than in those with biventricular atrioventricular connections (p = 0.016, chi-squared test). Complicated multiple orifices within the valvular curtain, including abnormal accessory orifices within a leaflet, were found in seven cases with double inlet to a dominant morphologically left or right ventricle. The presence of four papillary muscles was the most common pattern in hearts with double inlet ventricle. Straddling of the papillary muscles to a rudimentary and incomplete ventricle was seen in 23% of cases. Direct attachment of tendinous cords to the ventricular septum or parietal wall was seen 81% of hearts with double inlet.These features of the common valve found with double inlet atrioventricular connection seem less suited to function as the inlet valve supporting the systemic circulation. The recognized abnormal features should be identified preoperatively so as to plan more effective valvular plasty, or alternatively to establish different surgical strategies.

To extend the indications for corrective operation in patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries, surgical procedures were done to unify the blood sources for pulmonary perfusion. Since December 1985, 50 patients have undergone unifocalization at ages from 2 months to 26 years with a mean of 6 +/- 7 years. In total, 84 staged unifocalization procedures and 5 other palliative procedures were done in 49 patients. These included several operative procedures: simple ligation of major aortopulmonary collateral arteries in 8; pulmonary angioplasty in 29 including reconstruction of the pulmonary arterial tree by direct anastomosis or interposition between the central pulmonary arteries and the intrapulmonary arteries; construction of artificial central pulmonary arteries with use of a xenograft pericardial tube graft in 36 with no native central pulmonary arteries detected; and construction of supplemental central pulmonary arteries also with use of a pericardial tube graft in 10. The pericardial tube graft, if used, was anastomosed to the intrapulmonary arteries on one end and connected to a prosthetic tube on the other end so as to perfuse the reconstructed pulmonary arteries. The anastomosis was made inside the lung through the divided interlobar fissure. Five patients died after operation among those undergoing these 89 preparative operative procedures. Deaths were related either to bleeding caused by anticoagulation therapy administered to prevent thrombosis within the xenograft pericardial tube graft used or to progressive congestive heart failure as a result of an excessive amount of pulmonary blood flow. Twenty-six patients have undergone intracardiac repair after previous unifocalization. In 16 patients the artificial central pulmonary arteries surgically constructed were connected to each other and then an external conduit was placed. In another patient, intracardiac repair and unifocalization could be concomitantly achieved via a median sternotomy. The right ventricle to left ventricle systolic pressure ratio immediately after intracardiac repair in 27 patients ranged from 0.24 to 0.91 with a mean of 0.54 +/- 0.17. One patient (4%) died shortly after intracardiac repair because of thrombosis within the pulmonary arteries. Postoperative catheterization showed that pulmonary vascular resistance was correlated significantly with the number of pulmonary vascular segments functioning rather than with the condition of the central pulmonary arteries. We conclude that surgical unifocalization is a feasible procedure before subsequent intracardiac repair, even in patients with critically hypoplastic or absent central pulmonary arteries.

OBJECTIVE To clarify the precise anatomic arrangement of the annular attachment of a common atrioventricular valve in the setting of visceral heterotaxy. METHODS One hundred and twelve autopsied specimens with isomeric atrial appendages were studied. RESULTS Annular hinge points with a planar orientation were found in only 7 hearts. All others showed a nonplanar and undulating arrangement, including 7 with Ebsteins's malformation. When the posterior half of the valvar attachment was taken as a reference plane, the anterior part deviated superiorly, the distance from the plane to the anterior point being 6.7 +/- 4.9% of the circumferential length of the annulus. The ratio of the antero-posterior diameter to the width of the annulus was smaller in hearts with biventricular connections (0.77 +/- 0.15) than in those with double inlet ventricle (0.89 +/- 0.17, P < 0.001). Reflecting this, the ratio of superior deviation of the anterior valvar annulus compared to the antero-posterior diameter was greater in hearts with biventricular atrioventricular connections (P = 0.016), particularly in those with isomeric right appendages. No significant differences were found when the data was analyzed according to variations in ventricular morphology. CONCLUSIONS The precise evaluation of the annular structure of a common atrioventricular valve may well prove to be of clinical significance so as optimally to achieve valvar annuloplasty.

As we have tried to demonstrate in this chapter, extensive understanding of morphology is necessary for successful definitive repair in individual patients with isomeric atrial appendages, as well as for the further evolution of optimal surgical strategies. Obviously different from patients with the usual atrial arrangement, those with isomeric atrial appendages have specific morphologic features that may underscore the clinical problems frequently found in this setting. Surgical strategies as well as individual operative procedures should be established on the basis of knowledge regarding those features presently demonstrated, namely, ventricular structures, the atrioventricular valves, the coronary circulation, and so on. Further investigations will certainly provide other aspects of which we are at present unaware.

BACKGROUND--The sinus node is known to be duplicated in hearts with bilateral right appendages, but its site is uncertain when both appendages are of morphologically left pattern. OBJECTIVE--To determine the earliest site of activation of the atria, and to assess this site of activation relative to the anticipated location of the sinus node in patients with isomeric atrial appendages. STUDY DESIGN--Electrophysiological recordings by epicardial mapping during operations through a median sternotomy. PATIENTS--Since 1987, 44 consecutive patients with isomeric right appendages and 23 with isomeric left appendages. RESULTS--In 77% of the patients with isomeric right appendages, the site of earliest activation was superiorly located at the junction of one or other atrium and a superior caval vein; in other words, in the anticipated site of a sinus node. In contrast, an inferior site of earliest activation at the junction of an atrium with an hepatic vein was most common in patients with isomeric left appendages (56%). The site of earliest activation was not related to the veno-atrial junctions in six patients with isomeric right appendages (14%), nor in five with isomeric left appendages (22%). Moreover, in six patients with isomeric right appendages (13%), and three with isomeric left appendages (13%), additional sites of earliest activation were observed when the dominant site was suppressed. The locations of the earliest activation observed by epicardial mapping did not always accord with those expected from the preoperative electrophysiological examination, nor did they always match the anticipated site of the sinus node as documented by previous histological investigations. CONCLUSIONS--Epicardial mapping showed marked variation in functional arrangement of the earliest atrial activation. This information could be of future use when planning surgical procedures.

Ninety-three patients with cardiac isomerism were treated surgically from July 1985 to June 1991. Among them, three patients with right and 14 with left isomerism underwent biventricular repair. Ages ranged from 4 months to 41 years (mean 4.8 years). Anatomic repair was accomplished in 15 patients and functional repair with the right ventricle used as the systemic ventricle in two patients. Methods of atrial septation to separate pulmonary venous flow from systemic venous flow included atrial partition with a straight patch in seven patients, intraatrial rerouting with a tailored baffle in five, and a Mustard-type atrial switch in five. One hospital death (5.8%) and two late deaths (12%) occurred. Two patients required reoperation (12%), one reconstruction of a stenotic systemic venous connection and one mitral valve replacement because of incompetence. Surgically induced complete atrioventricular block was not observed in any of the patients. Optimal atrial septation offers the possibility of biventricular repair for patients with acceptable intraventricular structure.

Although additional aortopulmonary anastomosis established by creating double outlet from the systemic ventricle and anastomosing the pulmonary trunk to the ascending aorta can undoubtedly provide an unobstructed outlet for the systemic ventricle, postoperative regurgitation of the morphologically pulmonary valve, if it occurs, may spoil the efficacy. To determine whether the pulmonary valve can be regurgitant, 11 patients undergoing this surgical option, six accompanying a Fontan-type operation and five associated with biventricular repair, were reviewed. Postoperative regurgitation was observed echocardiographically in five patients. One patient with severe pathologic changes of the valve showed progressive regurgitation, necessitating valve replacement two months after the aortopulmonary anastomosis. The other four patients, including one with slight thickening of the pulmonary leaflets, had previously undergone banding of the pulmonary trunk. Slight regurgitation in these cases appeared between one month and two years after the procedure, but then neither progressed nor regressed. Pathologic changes of the pulmonary valve, and previous banding, therefore, can be recognized as risk factors for postoperative regurgitation. The morphologically pulmonary valve, nonetheless, proved to be feasible for this surgical option unless it possessed severe organic changes.

The indication of Fontan type operation has been extending, but some cases on the boundary of the indication resulted in low cardiac output syndrome (LOS) postoperatively. Recently the inhalation of nitric oxide (NO) has been revealed to produce selective pulmonary vasodilatation, and it has come to be applied in the clinical setting. We experienced a case of 6-year-old boy with complex cardiac anomaly in whom the inhalation of nitric oxide was remarkably effective for the LOS caused by increased pulmonary vascular resistance after Fontan type operation. In the case various conventional treatments failed to improve his LOS during the weaning from a respirator on the second postoperative day. After the initiation of the inhalation of nitric oxide at a concentration of 6ppm, a rapid decreasing of pulmonary artery pressure concomitant with an improvement of hemodynamics were obtained. We concluded that the inhalation of nitric oxide is an effective strategy for the increased pulmonary resistance after Fontan type operation.

Two infants with congenital aortic valve stenosis underwent successful aortic root replacement with pulmonary autograft. One of the patients was 9 months and weighted 4.2 kg, and the other was 10 weeks weighing 4.6 kg. The former had undergone balloon valvotomy with a resultant severe aortic regurgitation. Operative method was basically similar to that taught by Ross. In terms of the right ventricular outflow reconstruction, however, left atrial appendage was utilized as the posterior wall while equine pericardial monocusp patch formed the anterior wall in the former patient. In the latter, morphology of the left atrial appendage was not suitable for the same kind of reconstruction, and nonvalved equine pericardial tube was used. Both of the patients eventually gained satisfactory circulatory condition. Advantages of aortic root replacement with pulmonary autograft are good competence without residual stenosis, avoidance of anticoagulation, and the high potential of future growth. So this operation is especially indicated for neonates and infants with left ventricular outflow obstruction.

Optimal configuration and hydrodynamic performance of "Valved Pericardial Roll (VPR)" as an external conduit was studied using a mock circulatory system which was able to simulate a right cardiac function of infants. Results were as follows: 1) Cardiac output produced by VPR was consistently higher than that by non valved pericardial roll. This result showed the hemodynamic effectiveness of VPR at early stage of operation. 2) Cardiac output by VPR tended to decreased as an elevation of afterload and/or an increment of pulse rate. This result exhibited that VPR had a comparable performance to the Ionescu-Sihley pericardial valve, a satisfactory performance of which was recognized clinically. 3) The optimal configuration related to the length of valve leaflet (LVL) were obtained from the simulation data. VPR with two leaflets produced the best performance when each LVL was design to be 95% of the roll diameter. Among the VPR with three leaflets, the best LVL was 85%. Thus far, VPR which was developed based on the above fundamental studies, indicated satisfactory performance as compared to the conventional surgical treatment.

A successful operation for acute and severe aortic regurgitation after balloon valvuloplasty together with mitral regurgitation is described in a 9-month-old infant. Aortic root replacement was performed using a pulmonary autograft, while the right ventricular outflow tract was reconstructed with an interposed left atrial appendage posteriorly and a heterologous pericardial patch anteriorly. Mitral valve reconstruction was also effectively accomplished. This combination of right and left ventricular outflow tract reconstruction has a good potential for growth and may provide a solution for the future in infants.

A female infant weighing 2.4 kg had respiratory distress at birth. She became dyspneic and hypercapnic and required intubation with assisted ventilation 11 days after birth. Because cardiac failure and respiratory failure did not improve, she underwent total correction at 26 days old, which consisted of VSD closure, right ventricular outflow tract reconstruction with valved porcine pericardial roll (VPR) and plication of both pulmonary arteries. She was weaned from the ventilator 11 days after operation and discharged at 12 weeks of age. One year later, reoperation was successfully performed for the replacement of the stenotic VPR with a transannular patch.

Between November, 1987 and May, 1990, definitive operation was performed in 7 infants for tetralogy of Fallot with absent pulmonary valve. Preoperative respiratory failure was serious in 5 patients and semi-emergency operation was done. Surgical procedure consisted of closure of ventricular septal defect, reconstruction of right ventricular outflow tract using heterograft valved pericardial roll and plication of aneurysmally dilated pulmonary artery with or without pulmonary artery suspension in 5 infants with severe respiratory distress and heart failure, operated on 26 days to 5 months of age. In the other two less symptomatic infants, operated on at 13 months of age, reconstruction of right ventricular outflow tract was performed by transannular bovine pericardial patch with monocusp. There were no operative death and six infants are doing well 6 months to 3 years postoperatively, but one patient died of prolonged respiratory infection and respiratory failure one year after operation. Postoperative pulmonary arteriogram revealed a 42 to 61 (mean 54) percent reduction in right and left pulmonary artery size in 3 patients who underwent extensive plication of pulmonary artery. We suggest that definitive plication with or without suspension of pulmonary artery, together with closure of ventricular septal defect and reconstruction of right ventricular outflow tract is supposed to eliminate air way obstruction.

Total repair for truncus arteriosus using an external conduit was performed in 12 patients from 1978 through 1989. Six cases were infants (mean age: 3.4 months) and 6 were children (mean age; 1 years 9 months). Two cases had Collet-Edwards type II truncus and the other 10 cases had type I truncus. One of the infants was associated with an interruption of the aorta and another had a severe regurgitation of the truncal valve (TrV). For external conduits, we used a non-valved conduit in one infant, a composite valved conduit of Dacron containing a heterograft valve in 4 children and a valved pericardial roll made of an autologous or porcine pericardium in 5 infants and 2 children. One infant with a severe regurgitation of the TrV needed valve replacement along with enlargement of the annulus of the TrV. One infant who had replacement of the TrV died early postoperatively. Another infant died 10 months after total repair due to an infection of an external conduit. Cardiac catheterization was performed in all 10 survivors. The mean value for the systolic pulmonary/systemic pressure ratio decreased from 0.98 +/- 0.09 preoperatively to 0.36 +/- 0.09 postoperatively. Replacement of an external conduit was performed due to a conduit stenosis in 2 children and 1 infant, 10 years and 2 months, 7 years and 9 months, and 1 year and 8 months after the total repair, respectively. In one of these 2 children, replacement of the aortic valve was performed due to a severe aortic regurgitation. We conclude that our results of total repair for truncus arteriosus were satisfactory. However, it remains to be solved how to manage an infant with truncus arteriosus associated with a severe regurgitation of the TrV.

A 5-years old boy, whose thoracic situs was right isomerism, was diagnosed as transposition of great arteries, common atrioventricular canal (intermediate type), severe tricuspid valve regurgitation, pulmonary valve stenosis, bilateral superior vena cava and left sided inferior vena cava. The preoperative RVEDV was 95% and LVEDV 160%, and LV/RV pressure ratio was 0.54. Atrial rerouting using pericardial patch, replacement of tricuspid valve and pulmonary valvotomy were performed. Postoperative course was uneventful. This was a rare case of right isomerism who received biventricular repair.

The effect of pulsatile pulmonary flow after the modified Fontan procedure was examined in a model that simulated the right heart. An inlet overflow tank (preload), axial pulsatile pump, Wind-Kessel model (afterload), and an outlet overflow tank were connected in series. The standard conditions were flow 2.00 l/min with 12 mm Hg preload pressure, 3.0 Wood units resistance, and an outlet overflow tank pressure at 6 mm Hg. The pump rate was set at 80 beats/min. The simulated pulmonary arterial pressure and pulmonary flow waves produced by this model closely resembled those obtained from patients who had undergone the modified Fontan procedure. All variables except the preload were fixed and changes in pulmonary flow were examined at preload pressures of 8, 12, 15, and 17 mm Hg. As the peak pulmonary arterial pressure increased so did pulmonary flow, until it was greater than during the non-pulsatile state. Because the afterload of this model was fixed, this result suggests that there was a concomitant decrease in resistance. This model indicates that pulsatile pulmonary blood flow is likely to have a beneficial effect on the pulmonary circulation after the modified Fontan procedure.

A 8-year-old boy with a double inlet right ventricle with a non-confluent pulmonary artery was operated on with a modified Fontan operation. He had right isomerism, right aortic arch, bilateral superior caval veins, and left-sided inferior caval vein. Hepatic veins were separately drained to the right-side atrium. Left Blalock-Taussig shunt and right central shunt operations had been previously performed. Firstly, we had reconstructed the central pulmonary artery with a 16 mm porcine pericardial roll to unify the nonconfluent pulmonary arteries. Secondly, about 2 months after the first operation, we performed a modified Fontan operation. Systemic venous return from the inferior caval vein and the hepatic veins were drained to a reconstructed pericardial roll with an intraatrial Gore-Tex graft, and bilateral superior caval veins were also anastomosed to the roll. The structure of the pulmonary arterial system is one of the most important factors to determine the outcome of a modified Fontan operation. Even if the central pulmonary artery is absent, however, a modified Fontan operation is applicable for the patient whose peripheral pulmonary arteries have enough growth.

A 5-year-old boy with double inlet left ventricle and ventriculoarterial discordance (SDD type) underwent ventricular septation with arterial switch procedure. Previously he had received pulmonary arterial banding at 3 months-old. Preoperative cardiac catheterization revealed Qp/Qs 1.26, Pp/Ps 0.19 and LVEDV was 315% of normal (as left ventricle). Arterial switch with Lecompte modification was performed in order to separate ventricle with straight patch could be done. Post operative course was uneventful and patient was extubated 4 post operative day. These procedures had employed in this patient as follows; 1) systemic ventricle could be constructed with morphological left ventricle with mitral valve. 2) left ventricular outflow tract stenosis due to ventricular outlet foramen occasionally observed in conventional procedure such as intraventricular rerouting could be prevented, and 3) ventricular septation could be easy and simple with straight patch.

67Ga imaging was performed in sixteen patients (age: 8 m.-18 y.) who had persistent fever and positive acute phase reactants after surgery for congenital heart disease. Abnormal uptake of 67Ga over the heart and the lungs was evaluated with a computer. Abnormal uptake of 67Ga was observed in seven patients, three of them showed it in the area of peripheral pulmonary artery and another four showed it in the area of artificial vessels for pulmonary artery reconstruction. In six patients with positive blood cultures, five showed abnormal uptake of 67Ga and in ten patients with negative blood cultures, two showed it. Vegetation was detected with 2D-echocardiography in four patients and all of them showed abnormal uptake of 67Ga, while in 12 patients without vegetation three showed it. In conclusion, 67Ga imaging was useful to detect the foci of infective endoarteritis or pulmonary embolism caused by the vegetation in infective endocarditis in the patients after surgery for congenital heart disease, especially in the peripheral pulmonary arteries and artificial vessels which could not be detected with 2D-echo.

The effect of pulsatile pulmonary flow and the characteristics of pulmonary arterial pressure (PAP) trace were examined using a model simulating the right heart following the modified Fontan procedure. An inlet overflow tank (preload), valveless axial pulsatile pump, Windkessel model (afterload), and an outlet overflow tank (left atrium) were connected in series. Standard conditions were: flow 2.00 l/m, with 12 mmHg preload, 3.0 wood units resistance and left atrial pressure at 6 mmHg. The pump rate was set at 80 bpm. Simulated PAP and pulmonary flow (PF) waves produced by this model closely resembled those obtained from patients who had undergone the modified Fontan procedure. Parameters except preload were fixed and changes in PF were examined at varying preload of 8, 12, 15 and 17 mmHg. At the various preload levels, PF increased to values greater than the PF for the same conditions in the non-pulsatile state. With a preload value of 8 mmHg, PF increased from 1.10 l/m (non-pulsatile) to a maximum of 1.55 l/m at a peak PAP of 14 mmHg. With a preload of 12 mmHg, the PF increased from 2.00 l/m (non-pulsatile) to 2.65 l/m at 19 mmHg peak PAP. A preload of 15 mmHg resulted in an increase in PF from 2.65 l/m (non-pulsatile) to 3.30 l/m at 22 mmHg peak PAP, and when the preload was 17 mmHg the PF increased from 3.15 l/m (non-pulsatile) to 3.80 l/m at 25 mmHg peak PAP. The afterload of this model was fixed so the increase in PF with pulsation suggests a decrease in resistance.(ABSTRACT TRUNCATED AT 250 WORDS)

The cardiac performance was evaluated in patients who had received arterial switch operation (AS-op) for transposition of the great arteries (TGA) in their infancy with special attention to postoperative supravalvular pulmonary stenosis (SVPS). AS-op was performed in 36 infants; 13 with simple TGA and 23 with TGA accompanied with ventricular septal defect. Nine patients had undergone pulmonary arterial banding with systemico-pulmonary shunt. The mean age at surgery was 7 months. Postoperative catheterization was performed on average of 15 months after surgery. The end-diastolic volume (EDV) and ejection fraction (EF) of the left and right ventricles (LV, RV) were calculated from biplane cineangiograms. LVEDV and RVEDV were normalized and expressed as % of normals. SVPS was defined as peak systolic pressure gradient of 50 mmHg or higher between the RV and the pulmonary artery (PA). The mean LVEDV, RVEDV, LVEF and RVEF values were all within the normal range. Inverse correlation was observed between the peak systolic RV-PA pressure gradient and RVEF (n = 29, r = -0.84, p less than 0.001). SVPS after AS-op was observed in 8 patients (22%). Stenosis was observed at the site of anastomosis of the artery. In these cases, the diameter of the PA at the stenotic site decreased to 52% of the preoperative values. Branch stenosis of the PA was observed in 3 patients who had undergone surgery during the neonatal period. Generally, the results after AS-op were satisfactory in terms of cardiac performance. Postoperative SVPS was observed in 8 patients (22%) with decreased RVEF. Careful observations of the growth of PA after AS-op are mandatory.

The results of aorto-coronary bypass surgery in 28 children with coronary artery lesions due to Kawasaki disease were evaluated. Ages at surgery ranged from one to 17 years, and the intervals from disease onset to surgery ranged from 2 months to 16.8 years. All patients were followed by selective coronary arteriography, thallium myocardial imaging, ECG at rest, and the Master double step and treadmill exercise tests. The surgical outcomes were analyzed by comparing the results of pre-operative examinations with those of one month, one year, and more than 3 year post-operative examinations. At one month, one year, and more than 3 year post-operative examinations, the incidences of patency of internal mammary artery graft (IMAG) were 29/30 (97%), 25/29 (86%), and 7/8 (88%), and those of patency of saphenous vein graft (SVG) were 6/7 (86%), 6/9 (67%), and 3/7 (43%), respectively. Three patients out of 4 who showed occlusion of their IMAGs within one year after surgery, and one deceased case apparently had problems related to the surgical procedures, such as the timing of surgery, reconstruction of the main trunk of coronary artery and the site of anastomoses between aneurysms. Pre-operative, one month, and one year post-operative thallium myocardial imagings were compared to examine the changes of regional myocardial ischemia in 24 children, and 28 IMAGs and 8 SVGs were evaluated. In the 28 IMAGs, 14/28 (50%) showed improvement of the myocardial ischemia, and 2/28 (7%) showed deterioration at one month follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Between March, 1986 and May, 1988, extended direct anastomosis was performed for coarctation of the aorta (CoA) (5 infants) and interruption of the aortic arch (IAA) (3 infants). The aortic arch was hypoplastic in 3 patients. The incision was made in the inferior aspect of the aortic arch proximal to the origin of the carotid or brachiocephalic artery, which was then anastomosed to the descending aorta. Pulmonary artery banding was placed in 4 patients with associated complex cardiac anomalies. Aortic cross-clamp time was 19-54 minutes (mean 41 minutes). Pressure gradient between upper and lower extremity was 0-10 mmHg (mean 4 mmHg). There were no operative deaths and no neurologic complications. The peak flow velocity at the site of aortic reconstruction measured by Doppler echocardiographic study after surgery was 1.2-2.5 m/sec (mean 1.7 m/sec). This procedure has the advantages of leaving the subclavian artery intact and no aortic shelf tissue. And it can be applied in IAA or CoA with hypoplastic aortic arch.

The preoperative evaluation, surgical course, and early follow-up results of 5 infants less than 4 months of age who underwent aortic valvotomy for severe valvular stenosis between 1983 and 1985 were reviewed to determine the early prognosis of these neonates. Two of the 5 patients had been used respiratory support due to severe congestive heart failure and dyspnea. Emergency aortic valvotomy was performed in all during cardio-pulmonary bypass which achieve maximal relief of the stenosis without significant causing aortic insufficiency. There was a single operative death and there was one late death at 2 months after surgery who was regarded to have a extensive endocardial fibroelastosis. The other three patients have had a favorable early prognosis during mean follow-up period of 1.78 (0.4-3.8) years. They had been followed by means of two-dimensional and doppler echocardiography, which inferred that the aortic pressure gradient had been kept under 41 mmHg and which indicated that there were no LV enlargement to prove significant aortic valve insufficiency. These results indicate that early infants with severe valvular stenosis can undergo sufficient valvotomy safely and have a favorable early prognosis.

The reaction between phenyl methyl sulphonium bis(methoxycarbonyl)methylide and either acetic anhydride or benzoyl peroxide proceeds via “Pummerer” type rearrangement to afford phenyl α-acyloxymethyl sulphide. The kinetic data suggest that the rate-determining step involves SC bond cleavage after initial acylation or acyloxylation and subsequent proton removal by acyloxy anion unlike the corresponding reaction of the analogous sulphoxide with acetic anhydride in which the rate determining step is proton removal.

Carbodithioic acids react with trivalent sulphur compounds bearing semipolar linkages (sulphoxides, sulphonium ylides and sulphilimines), to give the corresponding sulphides and add to olefins to afford dithioesters. The orientation of olefin addition is controlled by the olefin nature. Michael type addition takes place with olefins bearing an electron-withdrawing group α to the double bond while Markownikoff addition occurs with olefins bearing an electron-donating group. With vinyl and allyl sulphoxides, both addition and reduction took place simultaneously, and new dithioesters were obtained.