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R Aeba

Publications and source records attributed to R Aeba.

At least 37 records · Page 2Linked to original sources
PubMed1998

[The role of bidirectional cavopulmonary shunt on selection of Fontan patients].

There are no objection against that pulmonary vascular resistance index (PVRI) is one of the most important factors for completion of successful application of Fontan-type operation. However, calculated PVRI in single ventricle physiology in often unreliable because of difficulty in accurate measurement of pulmonary blood flow, especially in patients with decreased pulmonary blood flow. Although the role of bidirectional cavopulmonary shunt (BCPS) in such patients has been increasingly recognized, the impact of BCPS on PVRI has not been fully understood. Between November 1993 and November 1996, 24 patients, aged between 0.54 and 22.2 years, with a wide variety of cardiac malformations underwent BCPS, and were followed up for the mean of 15.1 months. There were four hospital deaths (16.7%) and three deaths in follow-up (12.5%). Serial catheterization revealed that significant increase in mean arterial oxygen saturation from 75.8% to 83.9% (p = 0.005), and decrease in mean Nakata's index from 433 to 311 (p < 0.0001). PVRI calculated by using formulas derived from Ohm's law before BCPS (Pulmonary flow was derived from Fick formula) was highly (greater than 10 u.m2) or moderately (between 4 and 10 u.m2) elevated in 6 and 7 patients, respectively. However, PVRI in these patients was normal after BCPS. Fourteen out of 24 patients underwent total cavopulmonary connection (TCPC) with 8 to 15 months of interval from BCPS, and have been currently surviving, and in NYHA functional class I or II, except 2 patients who underwent take-down. In conclusion, early and midterm outcome after staged operation appears to be excellent. BCPS is a good interim procedure, in part because one can more properly select patients undergoing Fontan operations from the PVRI point of view.

Adolescent↗
PubMed1998

[Surgical repair of isolated congenital tricuspid regurgitation with artificial chordae--a case of two year-follow up].

Isolated congenital tricuspid regurgitation derived from primary dysplasia of the valvular apparatus is a rare cardiac abnormality. A 23-year-old woman was first diagnosed to have an isolated tricuspid regurgitation during infancy and was followed up at our hospital. She developed progressive cardiomegaly at the age of 22 years. The chest roentgenogram at the time of admission revealed marked cardiomegaly with a cardiothoracic ratio of 64%. Despite the severe regurgitation of the tricuspid valve, the catheter examination disclosed v and mean pressures of the right atrium of 9 mmHg and 5 mmHg, respectively. The operative findings revealed a markedly dilated tricuspid annulus of 45 mm in diameter (157% of normal) and fragile and redundant valve leaflets, anterior leaflet in particular. Anterior papillary muscle was absent without any vestige thereof. Chordae tendinae of the anterior and posterior leaflets were absent and those of the septal leaflet were attached to the ventricular septum. Each commissure was tethered to the ventricular wall by thick and short chordal tissue. The chordal abnormalities were repaired by four artificial chordae of 4-0 ePTFE suture and an annuloplasty with Carpentier-Edwards ring (36 mm) was added. She recovered uneventfully and was discharged on postoperative day 30. A follow-up echocardiography at 2 years after surgery showed excellent function and trivial regurgitation of the valve. No evidences of thrombus or calcification of the artificial chordae were detected. This experience draws us to conclude that the artificial chordal replacement is one of the useful surgical options for the repair of isolated congenital tricuspid regurgitation.

Adult↗
PubMed1998

Complications following reparative surgery for aortic coarctation or interrupted aortic arch.

Repair of aortic coarctation or interrupted aortic arch continues to be associated with major long-term morbidity. Thus, we conducted a review of 87 consecutive patients who underwent aortic arch repairs, focusing particular attention on the complications that developed. A two-stage strategy was employed if cardiac lesions were associated. The median age at surgery was 1.5 months with a range of 12 h to 56 years. The aortic arch was repaired using end-to-end anastomosis, subclavian flap aortoplasty, subclavian arterial turning-down aortoplasty, patch aortoplasty, tube graft interposition, or other methods. There were 10 patients who died soon after repair, and all of whom had complex cardiac anomalies. Of the remaining 77 patients, 8 developed recurrent stenosis. These 8 patients were all similar in age, being under 3 months old, and weighing 4 kg or less. A multivariable analysis of the infants identified interrupted aortic arch as an independent risk factor for the development of this complication with an odds ratio of 6.45. Complications following prosthesis-free techniques were similar in prevalence and timing. All reinterventions were mortality-free, but catheter dilation and patch aortoplasty were not always successful. Three extraanatomic bypasses were successfully performed, and one adult who had undergone a previous graft and pseudoaneurysm operation was successfully treated with an extraanatomic bypass. These findings led us to conclude that the initial repair should be performed without a prosthesis, and that reintervention for stenosis should combine catheter dilation and extraanatomic bypass.

Adolescent↗
PubMed1998

Surgical management of isolated congenital tricuspid regurgitation.

BACKGROUND: Isolated congenital tricuspid regurgitation without downward displacement of the leaflet is a rare clinical entity. Degenerative cusps and lack of chordae may preclude valvuloplasty and require valve replacement. METHODS: Three consecutive patients with isolated congenital tricuspid regurgitation underwent surgical repair between May 1995 and April 1997. Their ages were 23, 15, and 8 years old. Tricuspid valvuloplasty was feasible in all of them, with use of a gathering suture of the anterior leaflet, artificial chordae implantation, and ring annuloplasty. RESULTS: All 3 patients survived and recovered well after the operation. The cardiothoracic ratios on their chest roentgenograms decreased from 0.64 to 0.52 in patient 1, from 0.58 to 0.48 in patient 2, and from 0.60 to 0.44 in patient 3. Postoperative echocardiograms showed competent tricuspid valves and the disappearance of regurgitation in all cases. CONCLUSIONS: Although malformation of the valve is extensive in isolated congenital tricuspid regurgitation, application of artificial chordae with conventional valvuloplasty technique can avoid the use of prosthetic valves by establishing the competence of the tricuspid valve.

Adolescent↗
PubMed1998

Correction of total anomalous pulmonary venous connection of the cardiac type.

Surgical treatment of the cardiac type of total anomalous pulmonary venous connection requires special techniques. The treatment and outcome in 17 consecutive patients who had undergone primary repairs of the cardiac type between 1965 and 1996 were reviewed. The median age was 3 months and median weight 4.2 kg. The connection was the coronary sinus in ten patients, and the right atrium in six. Interatrial communication was routinely augmented. The right atrial cavity was partitioned using a patch to direct the anomalous pulmonary veins into the left atrium through the atrial septal defect in the first 13 patients. In the last four patients, the free wall flap of the right atrium was developed as a neoseptum. There were three early postoperative deaths during the early period of conventional repair. Two patients developed residual or recurrent diffuse obstruction in the individual lobar veins; reoperation to relieve the obstruction was attempted but unsuccessful. One sudden death occurred in a patient with occasional heart block. Ten survivors have been asymptomatic during follow-up, but two incomplete heart blocks and one atrial flutter were noted among patients who underwent conventional repair. The right atrial wall flap technique was not associated with any mortality or morbidity, such as arrhythmia and recurrent pulmonary vein stenosis during 12 to 63 months of postoperative obstruction. In conclusions, a flap technique using the right atrial wall appears to be a promising method to decrease the incidence of supraventricular arrhythmias and pulmonary vein drainage obstruction following repair of the cardiac type.

Cardiac Surgical Procedures↗
PubMed1997

Detrimental effects of exogenous glutamate on spinal cord neurons during brief ischemia in vivo.

BACKGROUND: Paraplegia remains a serious complication of thoracoabdominal aortic operations. However, despite growing in vitro evidence, it has been difficult to demonstrate glutamate neurotoxicity in vivo because of the reuptake activity that occurs. We hypothesized that glutamate can be toxic to the spinal cord under metabolic stress. METHODS: Infrarenal aortic isolation was performed in New Zealand white rabbits. Group A animals (n = 7) then received a segmental infusion of glutamate (50 mmol/L) for 5 minutes. Group B animals (n = 7) received saline as a negative control. Group C animals (n = 6) were pretreated with a segmental infusion of 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)-quinoxaline (4 mg/kg), a competitive alpha-amino-3-hydroxy-5-methylisoazole-4-propionic acid/kainate antagonist, followed by the segmental infusion of glutamate (30 mmol/L) for 4 minutes. Group D animals (n = 6) received the vehicle agents only, followed by the same glutamate infusion (30 mmol/L) as in group C as a control for group C. Neurologic status was assessed at 12, 24, and 48 hours after operation and scored using the Tarlov system. RESULTS: Group A animals exhibited paraplegia or paraparesis with marked neuronal necrosis. Group B animals recovered fully. Group C animals had better neurologic function than group D animals (p = 0.0039). CONCLUSIONS: Exogenous glutamate can have detrimental effects on spinal cord neurons during a brief period of ischemia. This model may be useful for the purpose of assaying a glutamate receptor antagonist in vivo.

Animals↗
PubMed1997

Long-term follow-up of surgical patients with single-ventricle physiology: prognostic anatomical determinants.

Although univentricular or biventricular repair is not always possible for hearts with single-ventricle physiology, it has been proven to produce a satisfactory outcome. It is hypothesized that patient prognosis can be predicted by anatomical diagnosis at presentation. Between 1961 and 1995, 158 patients with single-ventricle physiology, including tricuspid atresia and hypoplastic left heart syndrome, were referred to the authors' institute, and underwent 260 surgical interventions. Follow-up was 99% complete. Patient survival and anatomical risk factors were examined by the Kaplan-Meier method, and multivariate analysis including the Cox proportional hazard model. Mean (s.e.m.) actuarial survival rates at 1, 5, 10 and 20 years following birth were 70.3(3.6)%, 56.3(4.0)%, 48.8(4.2)%, and 40.9(4.7)%, respectively. Definitive palliation was attempted in 38 patients (univentricular in 35 and biventricular in three). Multivariate analysis identified systemic ventricular outflow tract obstruction, mitral atresia, situs ambiguus, and pulmonary vein drainage tract obstruction as independent prognostic factors for overall survival. Visceral heterotaxy was the only independent risk factor for lack of application or failure (death or take-down within 30 days of operation) of univentricular or biventricular repair. In conclusions, these anatomical factors in hearts with single-ventricle physiology affect long-term mortality, despite multiple and heterogeneous surgical efforts.

Female↗
PubMed1997

[Extra-anatomic bypass from the ascending aorta to the supraceliac abdominal aorta--surgical option applied to reoperation for aortic coarctation or interruption].

The optimal approach for reoperation following repair of aortic coarctation (CoA) or interruption (IAA) remains controversial. Four patients underwent extra-anatomic bypass for restenosis after repair of CoA or IAA. The age ranged from 4 to 12 years. The initial repairs for two CoA, one type A-IAA, and one type B-IAA consisted of two grafting, one subclavian arterial turning-down aortoplasty, and one subclavian flap aortoplasty. All of them underwent during infancy. Preoperative right arm systolic pressure ranged from 140 to 190 mmHg ar rest. Through a midline sternotomy and an upper laparotmy incision, an extra-anatomic bypass from the ascending aorta to the supraceliac abdominal aorta was employed using a 12 to 18 mm tube graft. All patients survived surgeries, and their hypertension markedly improved. Our experience confirms safety and effectiveness of this option in selected young patients with re-stenosis of following repair of CoA or IAA.

Aorta↗
PubMed1994

Effect of cardiopulmonary bypass on early graft dysfunction in clinical lung transplantation.

The records of 100 lung transplant recipients (13 heart-lungs, 45 double-lungs, and 42 single-lungs) from September 1990 through April 1992 were reviewed to determine the role of cardiopulmonary bypass (CPB) in early graft dysfunction. Fifty-five patients requiring CPB (CPB group) for 186 +/- 54 minutes were compared with the 45 patients without CPB (no-CPB group). All of the heart-lung and en-bloc double-lung transplantations were performed under CPB, with pulmonary vascular lung disease the principal diagnosis, resulting in a significantly younger age population in the CPB group. All other donor- and recipient-related factors matched well in both groups. Of 38 bilateral single-lung transplantations, CPB was used in 18. In double-lung and heart-lung recipients gas exchange of the allografts was evaluated by the arterial/alveolar oxygen tension ratios at nine intervals during the first 72 hours. The mean arterial/alveolar oxygen tension ratio in the CPB group was 0.48 +/- 0.19, significantly lower than in the no-CPB group with 0.60 +/- 0.22 (p = 0.025). All patients had radiographic interpretation and scoring of pulmonary infiltrates from chest roentgenograms taken within 12 hours after reperfusion. The CPB group had more severe pulmonary infiltrates than the no-CPB group (p = 0.034). Prolonged intubation defined as 7 days or longer occurred significantly more often (29/55) in the CPB group than in the no-CPB group (8/45) (p = 0.003). Actuarial graft and patient survival at 1 month was better in the no-CPB group than in the CPB group (42/45 versus 44/55 [p = 0.05] and 43/45 versus 45/55 [p = 0.033], respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

[The surgical treatment of coarctation of the aorta and interruption of the aortic arch in the first three months of life--effectiveness of temporary bypass between the pulmonary artery and the descending aorta].

From February 1987 to January 1994, we operated on 24 patients with coarctation of the aorta (CoA) and 9 patients with interruption of the aortic arch (IAA). A policy of staged repair was followed, consisting of reconstruction of the aortic arch with pulmonary artery banding and ligation of the ductus arteriosus in the first stage and intracardiac repair with pulmonary artery band removal in the second stage. In recent cases an extended aortic arch anastomosis was performed using a heparin-coated "shunt tube" between the pulmonary artery and the descending aorta to maintain blood flow to the lower half of the body during aortic cross-clamping. The use of the shunt increased intraoperative urine output (p < 0.05). This technique may allow patients whose condition is poor to undergo aortoplasty more safely. One patient died. This patient had CoA and total anomalous pulmonary venous return, who underwent a one-stage repair, in violation of our policy (early mortality 3.0%). There were two interim deaths before the second stage repair. At present, 18 patients have undergone staged intracardiac repair, including VSD closure (14 cases), Jatene's procedure (1), Ratelli's procedure (1), Damus-Kaye-Stansel (DKS) procedure (1), total cavo-pulmonary connection (TCPC) + DKS procedure+annuloplasty of a common atrioventricular valve (1). There were two early deaths and one late death following intracardiac repair, all in patients with IAA plus VSD.

Anastomosis, Surgical↗
PubMed1993

Isolated lung transplantation for patients with Eisenmenger's syndrome.

BACKGROUND: Eisenmenger's syndrome remains one of the greatest challenges in lung transplantation. METHODS AND RESULTS: Since October 1990, seven such patients with Eisenmenger's syndrome received isolated pulmonary grafts (six double lungs and one single lung). Mean patient age was 32 +/- 6 years (two men and five women). The preoperative mean pulmonary arterial pressure was 90.7 +/- 31.2 mm Hg, and the ventriculoscintigram showed markedly enlarged right ventricle and normal left ventricular function with ejection fraction of 0.660 +/- 0.115. Three atrial septal defects and four patent ducti arteriosus were repaired concomitantly. Excised lung histology showed plexogenic pulmonary arteriopathy with Heath-Edwards' grade 4 through 6. One double lung patient who had preexisting systemic vascular collapse died intraoperatively. The other six patients tolerated transplantation, and on the first operative day, mean pulmonary artery pressure decreased to 22.4 +/- 7.3 mm Hg (P < .002) and gas exchange was acceptable with an arterial/alveolar oxygen tension ratio of 0.47 +/- 0.15. Two patients died of mediastinal and pulmonary infection. The follow-up for the four survivors ranged from 13 to 25 months after transplantation. CONCLUSIONS: Our preliminary experience shows that concomitant isolated lung transplantation with cardiac repair could be a viable therapeutic option for patients with Eisenmenger's syndrome and normal left ventricular function. Dynamic right ventricular outflow obstruction is a potential hemodynamic problem in these pulmonary recipients.

Adult↗
PubMed1993

Aspects of lung transplantation that contribute to increased severity of pneumonia. An experimental study.

In lung or heart-lung transplant recipients, complications as a result of pulmonary infections continue to be the most frequent causes of morbidity and mortality. This study was undertaken to identify the contributions of (1) thoracotomy, (2) interruption of lymphatic vessels and bronchial arteries, (3) transplant procedure, (4) drug-induced immunosuppression, and (5) graft allogenicity to the increased risk of pneumonia in lung transplantation. Lewis rats were inoculated with 10(5) colony-forming units of Legionella pneumophila serogroup 1 by direct instillation into the trachea after one of the following: a general anesthetic with no operation; a left thoracotomy; a left thoracotomy with pulmonary hilar stripping; an isogeneic orthotopic left lung transplant with or without immunosuppression; or an allogeneic transplant with immunosuppression with Brown-Norway rats as donors. Immunosuppression was induced with an intramuscular injection of cyclosporine (25 mg/kg of body weight) from the inoculation day to day 3. All rats were killed on day 6, and severity of infection was determined by quantitative culture of Legionella organisms in the lungs and spleen, titer of Legionella urinary antigen, differential cell count in bronchoalveolar lavage fluid, body weight loss, and gross inspection of the lung. Significant increases in lung Legionella concentration occurred as a result of the addition of pulmonary hilar stripping (from 10(5.13 +/- 0.34) in the thoracotomy group to 10(5.66 +/- 0.25) in the thoracotomy with hilar stripping group, p = 0.013) and the addition of immunosuppression (from 10(5.47 +/- 0.47) in the isogeneic transplant group to 10(6.94 +/- 0.52) in the isogeneic transplant with immunosuppression group, p = 0.00016). Thoracotomy, transplant procedures, and allogenicity itself resulted in no significant increases. The results for all other indicators paralleled those for lung culture. We conclude that the combination of drug-induced immunosuppression with lung denervation and interruption of lymphatic vessels and bronchial arteries results in the early development and increased severity of pneumonia in lung transplantation.

Animals↗
PubMed1993

A clinical trial of University of Wisconsin solution for pulmonary preservation.

Suboptimal pulmonary preservation with modified Euro-Collins solution (9/90 to 4/91) prompted us to change to University of Wisconsin solution (4/91 to 4/92). Between September 1990 and April 1992, 94 patients received 100 pulmonary allografts (13 heart-lungs, 45 double lungs, 42 single lungs) that were flushed and preserved with either Euro-Collins (n = 30) or University of Wisconsin (n = 70) solution. Selection of donors and procurement and storage of donor lungs were identical. Bilateral single lung transplantation was performed more often in the University of Wisconsin group and resulted in a significantly longer graft ischemic time (University of Wisconsin group; 303 +/- 62 minutes; Euro-Collins group; 260 +/- 62 minutes; p = 0.007, t test). The use of cardiopulmonary bypass was not statistically significantly different. Preservation injury identified by the radiograph on day 1 was more severe (p = 0.036; Mann-Whitney U test) in the Euro-Collins group than in the University of Wisconsin group. In double lung and heart-lung recipients gas exchange of the allografts was evaluated by the arterial/alveolar oxygen tension ratios at nine intervals during the first 72 hours. The mean arterial/alveolar oxygen tension ratio was 0.62 +/- 0.26 in the University of Wisconsin group and 0.46 +/- 0.23 in the Euro-Collins group, but this difference did not reach significance (p = 0.119, analysis of variance). Despite the longer ischemic time, pulmonary preservation achieved by University of Wisconsin solution appears to be comparable with that achieved by Euro-Collins solution.

Adenosine↗
PubMed1992

University of Wisconsin solution for pulmonary preservation in a rat transplant model.

University of Wisconsin and modified Euro-Collins solutions for pulmonary preservation were compared in a rat orthotopic left lung isotransplant model. Heart-lung blocks of donor rats were flushed with and preserved in one of the preservation solutions at 0 degrees C. After 6 or 12 hours of cold ischemia, the left lungs were transplanted into recipient rats and reperfused for 1 hour. Pulmonary function was assessed by measuring oxygen and carbon dioxide tensions in arterial blood after removal of the right lung. Lipid peroxide concentrations were measured as thiobarbiturate acid-reactive substances. The ratios of wet to dry weight of grafts after ischemia and after reperfusion were calculated. Histologic changes of ischemia-reperfusion injury of the lung tissue were evaluated using a graded scale. Oxygen tension after 6 hours of preservation followed by reperfusion was significantly higher with University of Wisconsin solution (308.8 +/- 81.1 mm Hg) than with Euro-Collins solution (50.8 +/- 17.8 mm Hg; p less than 0.001). Carbon dioxide tension in the University of Wisconsin solution group was also significantly lower than in the Euro-Collins solution group (28.2 +/- 2.3 versus 46.0 +/- 4.5 mm Hg; p less than 0.05). Lipid peroxide concentration after 6 hours' preservation in University of Wisconsin solution was significantly lower (0.88 +/- 0.07 mumol/g) than that in Euro-Collins solution (1.26 +/- 0.12 mumol/g; p less than 0.05). After 12 hours of preservation only lipid peroxide concentration with University of Wisconsin solution was significantly lower (1.30 +/- 0.09 mumol/g) than with Euro-Collins solution (1.71 +/- 0.15 mumol/g; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine↗
PubMed1992

Lazaroid U74500A as an additive to University of Wisconsin solution for pulmonary grafts in the rat transplant model.

Lazaroids are a class of novel 21 aminosteroids. They have been reported to be potent inhibitors of lipid peroxidation, which is a major contributing factor to ischemia-reperfusion injury in the lung. A Lewis rat orthotopic left lung isotransplant model was used to investigate the effects of the lazaroid U74500A on pulmonary preservation. The heart-lung blocks of donor rats were flushed with and then stored in either standard University of Wisconsin solution or University of Wisconsin solution with 30 mumol/L of U74500A substituted for the dexamethasone. After 6 or 12 hours of cold storage at 0 degrees C, the left lungs were transplanted into recipient rats and reperfused for 1 hour. Pulmonary function was assessed by measuring oxygen and carbon dioxide tensions in arterial blood after removal of the right lung. Lipid peroxide concentrations were measured as a thiobarbituric acid-reactive substance. Although arterial oxygen and carbon dioxide pressures and water content after 6 hours of preservation followed by reperfusion were similar in both the lazaroid and dexamethasone groups, lipid peroxide concentration was significantly higher in the dexamethasone group (0.88 +/- 0.07 mumol/gm) than in the lazaroid group (0.54 +/- 0.07 mumol/gm) (p < 0.01). After 12 hours of preservation, there were significant differences between the lazaroid and dexamethasone groups in arterial oxygen pressure (339 +/- 70 vs 27 +/- 3 mm Hg, p < 0.01), arterial carbon dioxide pressure (24.3 +/- 2.7 vs 47.7 +/- 7.0 mm Hg, p < 0.001), and lipid peroxide concentrations (0.69 +/- 0.07 vs 1.30 +/- 0.09 mumol/gm, p < 0.001). We conclude that addition of U74500A to the flush and storage solution enhances the preservation of the pulmonary graft in this transplant model.

Adenosine↗