Biomedical subjects

T Yagihara

Publications and source records attributed to T Yagihara.

At least 109 records · Page 6Linked to original sources

PubMed1993

Growth potential after root replacement of the right and left ventricular outflow tracts.

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.

Aorta, Thoracic↗

PubMed1993

Biventricular repair of cardiac isomerism with common atrioventricular canal with the aid of an endocardial cushion prosthesis.

Between 1983 and 1990, six patients with atrial isomerism associated with common atrioventricular canal and double-outlet right ventricle were operated on with the aid of an endocardial cushion prosthesis. This prosthesis, which has been used for the repair of common atrioventricular canal since 1975, is composed of a vertical Dacron patch and "wings" constructed from the patient's own pericardium, which are attached to both sides of the patch to compensate for the defective atrioventricular valve tissue. The ventricular portion of the patch was extended anteriorly to construct the route for blood flow from the left ventricle to the aorta. Intraventricular repair was performed through the common atrioventricular orifice in all patients and also through an additional right ventriculotomy in one patient. The complex systemic and pulmonary venous return was separated by use of the atrial part of the endocardial cushion prosthesis together with additional prosthetic materials. All patients survived the operation and were followed up from 1 to 9 years. All of them are doing well, although one patient has a significant interventricular residual shunt. Repair of atrial isomerism with common atrioventricular canal and double-outlet right ventricle with an endocardial cushion prosthesis was performed with satisfactory immediate and intermediate-term postoperative results.

Blood Vessel Prosthesis↗

PubMed1993

[Experimental study on the hydrodynamic performance of "valved pericardial roll"].

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.

Animals↗

PubMed1993

[Surgical management of tetralogy of Fallot with absent pulmonary valve in infancy].

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.

Bioprosthesis↗

PubMed1993

Intraventricular repair for Taussig-Bing anomaly.

Among 41 patients with Taussig-Bing anomaly who underwent intracardiac repair, 10 patients were treated by intraventricular rerouting repair. The ages at operation ranged form 1 month to 8 years (average 2 years 3 months). Primary repair was done in four (average age 2 years 7 months), and repair was done after pulmonary artery banding in six patients (average age 2 years 2 months). The relationship of the great arteries was side by side in nine patients and oblique in one. After extensive resection of the infundibular septum, a distance of 8 to 18 mm from the tricuspid ring or chordae to the pulmonary valve was obtained (24% to 71% of total circumference for the subaortic route). The subaortic route was created to obtain an internal diameter at least equal to that of the aortic route. Tricuspid chordal or papillary muscle reattachment was performed in two patients. There were no early or late deaths. Follow-up ranged from 1 year 4 months to 22 years 3 months (average 5 years 8 months), and reoperation was required in one patient for residual pulmonary stenosis. The intraoperative pressure gradient between the left ventricle and aorta was 0 to 24 mm Hg (average 10.3 mm Hg), and postoperative study showed the gradients to be less than 19 mm Hg (n = 8). The age at operation, left ventricular-aortic pressure gradient, and postoperative tricuspid regurgitation were not significantly affected by the presence of severe hypertrophy of the infundibular septum (n = 4). These results indicate that intraventricular rerouting may be feasible in most patients who have the Taussig-Bing anomaly with side-by-side or similar relationships of the great arteries, and the age and conal anatomic variations do not appear to be significant limiting factors.

Cardiac Catheterization↗

PubMed1993

[A case report of successfully corrected 26 days old infant of tetralogy of Fallot with absent pulmonary valve].

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.

Blood Vessel Prosthesis↗

PubMed1992

Late death after arterial switch operation for transposition of the great arteries.

Fifty-nine patients survived for more than 1 month after an arterial switch operation (ASO). Diagnoses in these patients included transposition of the great arteries in 27, transposition of the great arteries with ventricular septal defect in 28, and double-outlet right ventricle in four. There were six late deaths (10%) during the follow-up period, and all of them occurred suddenly and unexpectedly. Four of the six late deaths were in patients who had undergone ASO in the neonatal period. Late deaths occurred from 40 days to 10 months after the operation. Autopsies were performed in all six patients. The cause of these late deaths was acute myocardial infarction. Five patients died of subendocardial infarction resulting from stenosis of the left main coronary artery. On pathologic examination, a fibrocellular intimal thickening was noted at the proximal region of the right and left coronary arteries, which resulted in 80% stenosis on average.

Abnormalities, Multiple↗

PubMed1992

New surgical technique for total-defect aortopulmonary window.

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.

Aortopulmonary Septal Defect↗

PubMed1992

A model to simulate the haemodynamic effects of right heart pulsatile flow after modified Fontan procedure.

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.

Blood Pressure↗

PubMed1992

[Pulmonary uptake of thallium-201 in patients with congenital heart disease: comparison between total anomalous pulmonary venous connection and tetralogy of Fallot].

To evaluate the pulmonary extravascular space in patients with congenital heart disease, lung uptake of thallium-201 (T1-201) was quantitatively studied. A total of 50 T1-201 imagings were performed in 33 patients with total anomalous pulmonary venous connection (TAPVC); 4 preoperatively, 22 postoperatively in the early stage (within 6 months), and 24 in the late stage (7 months or later). The images consisted of 17 supracardiac TAPVC (type-I), 13 paracardiac (type-II) and 3 infracardiac (type-III). In patients with tetralogy of Fallot (T/F), T1-201 imaging was performed 15 times preoperatively, 12 in the early stage and 15 in the late stage, postoperatively. Furthermore, 29 patients with ventricular septal defect (VSD) or patent ductus arteriosus (PDA) were also studied preoperatively, and 21 in the late postoperative stage. Twenty-five patients with arrhythmias or a history of Kawasaki disease without perfusion defects were studied on T1-201 myocardial imaging. Lung uptake of T1-201 was analyzed with a computer using the anterior image of the chest, and the average count ratio of the right lung (P) to the left ventricular wall (LV) was calculated. P/LV values were compared between the patients before and after surgery, and differences in anatomical types in TAPVC were also evaluated. In TAPVC, P/LV values decreased gradually in the postoperative state, but were significantly higher than those of controls even in the late stage. In the late postoperative stage, type-I TAPVC had significantly higher P/LV values than those of type-II.(ABSTRACT TRUNCATED AT 250 WORDS)

Heart Defects, Congenital↗

PubMed1992

[Total repair for truncus arteriosus].

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.

Bioprosthesis↗

PubMed1992

[Biventricular repair for right isomerism associated with transposition of great arteries and common atrioventricular canal].

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.

Child, Preschool↗

PubMed1991

The effects of several pharmacologic agents upon postischemic recovery.

Using an isolated working rat heart model, the effects of DL-verapamil, ryanodine, gabexate mesilate (FOY), recombinant human superoxide dismutase (RH-SOD), and coenzyme Q10 upon myocardial protection were evaluated. Under conditions of normothermic ischemia, all these compounds, except RH-SOD, when added to the St. Thomas' cardioplegic solution at an optimal concentration, showed beneficial effects upon functional recovery and enzyme leakage. In contrast, the above compounds, except ryanodine and FOY, failed to improve the protective properties of the St. Thomas' cardioplegic solution under conditions of hypothermic ischemia. Our results indicate that calcium overload via the calcium channel and calcium-induced calcium release from sarcoplasmic reticulum (SR) may contribute to the onset of ischemic-reperfusion injury. However, under conditions of hypothermic ischemia, calcium-induced calcium release from SR plays a dominant role in calcium overload. Furthermore, intracellular calcium overload may activate proteases and result in the acceleration of myocardial injury.

Animals↗

PubMed1991

[67Ga imaging in the patients with infective endocarditis after surgery for congenital heart disease].

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.

Adolescent↗

PubMed1991

[Modified Fontan procedure, is the right atrial pump function necessary or not? Experimental approach using simulation model].

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)

Atrial Function, Right↗

PubMed1991

[Modified Fontan operation for a single ventricle with a nonconfluent pulmonary artery].

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.

Blood Vessel Prosthesis↗

PubMed1991

[Ventricular septation combined with arterial switch for a patient with double inlet left ventricle with right sided rudimentary right ventricle and ventriculoarterial discordance].

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.

Aorta↗

PubMed1991

[Cardiac performance before and after Jatene procedure for transposition of the great arteries: with specific reference to post-operative supravalvular pulmonary stenosis].

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.

Cardiac Surgical Procedures↗