Biomedical subjects

W J Brawn

Publications and source records attributed to W J Brawn.

At least 37 records · Page 2Linked to original sources

PubMed1996

Management and outcome of infants and children with right atrial isomerism.

OBJECTIVES: To assess the current results and outcome of surgery in infants and children with right atrial isomerism and complex congenital heart disease. SETTING: Tertiary referral centre. METHODS: 20 consecutive children with right atrial isomerism and complex congenital heart disease underwent surgery over a 6 year period between August 1987 and July 1993. The results and outcome were analysed according to age, presentation, and surgical procedures. RESULTS: Patients were divided into two groups depending on age at presentation and initial surgery: group A comprised 11 patients who required surgical intervention in the first month of life (mean age 5 days); and group B comprised nine patients who required initial surgical intervention after the first month of life (mean age 6.8 months). Seven (64%) of the 11 patients in group A had obstructed pulmonary venous drainage and ten (91%) had pulmonary atresia. There were seven early deaths (64%), including the five patients who required systemic to pulmonary artery shunt and simultaneous repair of obstructed pulmonary veins. The long-term survival rate in this group was 18% (two of 11). Pulmonary venous obstruction was present in two (22%) of the nine patients in group B and four (44%) had pulmonary atresia. There were no early deaths. One patient died after a second palliative procedure. There was one late sudden death. Four patients had a Fontan operation with no deaths. Two of the remaining three patients meet the Fontan criteria. The long-term survival rate in this group was 78% (seven of nine). CONCLUSIONS: Surgical management of patients with right atrial isomerism who have complex congenital heart disease carries a high mortality and remains palliative. The overall survival rate was 45% (nine of 20); 18% in patients requiring surgery in the first month of life (group A) and 78% in patients requiring surgery after the first month of life (group B) (P < 0.001). Of the total of 20 patients, nine were potential candidates for a Fontan operation. Seven of these have undergone a Fontan procedure with five survivors.

Child, Preschool↗

PubMed1995

Endocarditis with multiple intracardiac shunts: identification and repair.

An 8-year-old boy who suffered from Hirschsprung's disease had development of tricuspid valve endocarditis that progressed to aortic root abscess formation, development of a fistulous communication between aorta and right atrium, atrial and ventricular septal defects, and a left ventricle to right atrium defect. Several surgical procedures were required. Operation consisted initially of closure of the septal defects and aortic valve repair. This was followed by homograft replacement of the aortic valve for persistent infection, and further closure of a left ventricle to right atrium fistula.

Abscess↗

PubMed1995

Neonatal pulmonary vascular disease in hypoplastic left heart syndrome.

A term neonate with hypoplastic left heart syndrome underwent surgical palliation using the Norwood procedure on day 2 of life. The postoperative course was complicated by recurrent systemic desaturation leading to death. Postmortem histologic examination of lung tissue confirmed the clinical impression of fixed pulmonary vascular disease. Some neonates with a restrictive interatrial communication may have pulmonary vascular disease at birth, which will negatively influence survival irrespective of the type of palliation undertaken.

Fatal Outcome↗

PubMed1995

Univentricular heart with systemic outflow obstruction: palliation by primary Damus procedure.

In 24 consecutive infants (19 male and 5 female) with complex forms of single-ventricle physiology and systemic outflow obstruction, a modified Damus operation without the use of exogenous material was undertaken in conjunction with creation of an aortopulmonary shunt 3.5 mm in diameter. The median age at operation was 6 days (range, 1 to 170 days) and the median weight, 3.4 kg (range, 2.6 to 4.6 kg). There were nine early deaths. All 15 survivors (median follow-up, 6.5 months) were clinically well without major systemic ventricular dysfunction or atrioventricular or arterial valve regurgitation. Ten of them have undergone a superior vena cava-pulmonary shunt (one death), and 1 has required patch angioplasty of the aortic arch and innominate artery with revision of the aortopulmonary shunt. The 4 other survivors are awaiting a cavopulmonary shunt. Univariate analysis yielded the chronologic rank for an individual procedure (higher risk of death early in the series), presence of aortic arch atresia, and presence or absence of transposition of the great arteries as predictors of death. This aggressive surgical approach provides excellent early palliation, and because the operation prevents abnormal ventricular hypertrophy from pressure or volume overload, systemic ventricular function is optimally conserved for a future Fontan-type procedure.

Cardiac Surgical Procedures↗

PubMed1995

Intraoperative epicardial echocardiography in assessing pulmonary artery banding procedures.

BACKGROUND: Accurate perioperative assessment of the adequacy of pulmonary artery banding has hitherto relied on oximetry and direct pressure measurements. We report the use of epicardial Doppler echocardiography for assessing banding procedures. METHODS: Six consecutive infants (3 male, 3 female; median age, 17 days) who underwent pulmonary artery banding for complex defects were studied by intraoperative epicardial Doppler echocardiography. RESULTS: Excellent visualization of the relation of the band to the pulmonary valve and branch arteries was obtained, enabling or confirming optimal positioning. Doppler echocardiographic estimation of the pressure drop across the band was possible in each patient and resulted in further tightening of the band in 2 patients (33%) with satisfactory increases in transband pressure gradients. Intraoperative echocardiographic estimates of the transband gradients (median, 57 mm Hg; range, 52 to 71 mm Hg; mean +/- standard deviation, 59 +/- 7 mm Hg) correlated well with those obtained at subsequent transthoracic echocardiography (median gradient, 66 mm Hg; range, 52 to 67 mm Hg; mean +/- standard deviation, 63 +/- 6 mm Hg). CONCLUSIONS: Epicardial echocardiography is a valuable adjunct to direct pressure and saturation measurements for adjustment of final band size and aids in confirming accurate band placement.

Echocardiography↗

PubMed1995

Surgery for infants with a hypoplastic systemic ventricle and severe outflow obstruction: early results with a modified Norwood procedure.

OBJECTIVE: Prospective audit of the first year of implementation of a modified approach to palliation for infants with hypoplastic systemic ventricle and severe systemic outflow obstruction. SETTING: Tertiary referral centre for neonatal and infant cardiac surgery. PATIENTS AND METHODS: 17 of 19 infants (aged < 35 days) presenting to Birmingham Children's Hospital in 1993 with hypoplastic systemic ventricle and severe outflow obstruction underwent surgery. This was performed using a new modification of the Norwood-type arch repair, without the use of exogenous material, and a 3.5 mm Gore-tex shunt between the innominate and right pulmonary arteries. The Gore-tex shunt was replaced by a cavopulmonary shunt between 3 and 5 months later. Clinical, morphological, and functional determinants of outcome were examined. RESULTS: 10 (59%) infants survived initial surgery. All proceeded to cavopulmonary shunt without further loss. Significant atrioventricular valve regurgitation seemed to be the main risk factor for poor outcome. If this was excluded, the morphology of the dominant ventricle seemed to have little effect on the outcome of initial surgery. CONCLUSIONS: Early survival was achieved in 59% of patients in the first year of implementation of a protocol for surgery in infants with hypoplastic systemic ventricle and severe outflow obstruction. The construction of a neoaorta without the use of exogenous material may allow improved later growth of the neoaorta. Early cavopulmonary shunt can be performed safely and should reduce mid-term complications from cyanosis and systemic ventricular volume loading.

Female↗

PubMed1995

Combined atrial and arterial switch procedure for congenital corrected transposition with ventricular septal defect.

OBJECTIVES: A combined atrial and arterial switch procedure was performed in selected patients with congenitally corrected transposition to establish the morphological left ventricle as the systemic ventricle. Immediate and early follow up results are presented. BACKGROUND: Progressive right ventricular dysfunction and tricuspid regurgitation are common in patients with congenitally corrected transposition who undergo repair of associated lesions. A surgical procedure which re-establishes the left ventricle as the systemic ventricle should improve functional results. METHODS: Four symptomatic children aged from 9 months to 3 years 1 month (mean 2 years 3 months) with congenitally corrected transposition and ventricular septal defect underwent both an atrial and arterial switch procedure and were followed up for a mean of 12 months (range 6-21 months). RESULTS: There were no early or late deaths. Conduction abnormalities worsened in two patients. Hospital stay ranged from 8 to 17 days (mean 13 days). The cardiothoracic ratio decreased from a mean (range) of 0.65 (0.6 to 0.71) to 0.58 (0.52 to 0.6). Currently, three patients are in functional class I and one child is in functional class II. CONCLUSIONS: The combination of an atrial and an arterial switch procedure in symptomatic children with congenitally corrected transposition establishes the left ventricle as the systemic ventricle. The initial experience is encouraging with excellent immediate and early follow up results.

Child, Preschool↗

PubMed1995

The use of a glutaraldehyde-preserved ovine pulmonary valve, as a pulmonary valve substitute in infants.

Reconstruction of the right ventricular outflow tract with a valved conduit is often necessary to repair some forms of congenital heart disease. We have used a 12- to 13-mm sized glutaraldehyde-preserved lamb's (ovine) valve for this purpose. The valves were harvested from the local abattoir, dissected, and stored in glutaraldehyde at 4 degrees C for 2 weeks before use. The valve was placed in four infants, two with truncus arteriosus, one with aortic valve atresia and ventricular septal defect, and one with absent pulmonary valve syndrome. In three patients, the valve had to be replaced in the second year of life, and in one patient in the fourth year of life. All patients are alive and well at follow-up. In the short-term, this valve has functioned well and could be considered where commercially available conduits or homografts are not routinely available.

Animals↗

PubMed1994

Post-operative blood loss following cardio-pulmonary bypass in children.

Significant post-operative bleeding may occur following cardio-pulmonary bypass, sometimes necessitating early re-exploration. Two questions were asked by this study. Firstly, in children undergoing cardio-pulmonary bypass, can pre-operative, operative and immediately post-operative variables be used to predict post-operative blood loss? Secondly, in the same patient group, can the same variables be used to predict the surgical intervention of re-exploration for excessive bleeding within 12 h of surgery? In a prospective study of patients operated on in a 9-month period, bleeding fell rapidly in the first 3 h after surgery and early re-exploration for bleeding was necessary in 8 of the 206 patients. The only significant predictor of post-operative blood loss was minimum oesophageal temperature, low values being associated with greater blood loss (correlation r = -0.19 (P < 0.05)). With regard to re-exploration for bleeding, a long bypass time (P < 0.05) and abnormal pre-operative coagulation indices (P < 0.01) were significant and independent predictors. The data were also used to create a practical nomogram relating re-exploration for bleeding to hourly post-operative blood loss.

Body Temperature↗

PubMed1992

Interrupted aortic arch in infancy: a 10-year experience.

Fifty infants with interrupted aortic arch (IAA), admitted between 1979 and 1988, were reviewed. They usually presented early in severe cardiac failure or shock. In the initial 5-year period, 17 of the 21 infants underwent diagnostic or confirmatory cardiac catheterization, in contrast with the latter 5 years when only eight of the subsequent 29 patients underwent catheterization. Since 1987, all patients underwent surgery after cross-sectional echocardiography. Fifteen infants had a type A IAA and 35 had type B. All had associated cardiac anomalies. Four infants were not operated on. In the initial 5-year period, of 17 infants who were surgically treated, four had a one-stage total repair, the remaining had a two-stage repair with initial reconstruction of the arch and pulmonary artery banding. There was an overall surgical mortality of 65%, reflecting the precarious state of many of these infants before surgery with a significant contribution from unrelieved subaortic stenosis. In the latter 5-year period, 29 underwent surgery, 22 had a one-stage total repair. There were three deaths, all in infants whose active treatment was withdrawn. The outcome of the survivors has generally been good, subsequent surgery being mainly related to the associated anomalies (e.g., recurrent subaortic stenosis, conduit replacement). Over this 10 year period the greater accuracy of noninvasive diagnoses, and perioperative intensive care, have led to an improvement in the preoperative state of these infants. Single-stage total repair is our procedure of choice.

Aorta, Thoracic↗

PubMed1992

Cardiac conduction abnormalities and rhythm changes after neonatal anatomical correction of transposition of the great arteries.

Seventy three infants who underwent neonatal anatomical correction for transposition of the great arteries with or without a ventricular septal defect were reviewed for evidence of conduction and rhythm abnormalities on preoperative and postoperative 12 lead electrocardiograms and during 24 hour Holter monitoring. There was a partial right bundle branch block pattern in 47% (29/62) of all patients and in 60% (24/40) of those with simple transposition. Complete right bundle branch block was noted in 21% including 5% with simple transposition. Holter monitoring showed sinus rhythm in all patients except three: one had episodes of supraventricular tachycardia, another an intermittent second degree heart block, and a third a complete heart block. Atrial extrasystoles were noted in 47% (29/62) of patients but were frequent in only three patients. Occasional unifocal ventricular extrasystoles were encountered in 37% (23/62) of patients and were frequent in a further 3% (2/62). Only one patient (2%) developed multifocal ventricular extrasystoles. The frequency of important cardiac arrhythmias after neonatal anatomical correction of transposition of the great arteries was 5%, significantly less than that reported after atrial inflow diversion for the same malformation.

Arrhythmias, Cardiac↗

PubMed1991

Tracheoaortopexy via midline sternotomy in tracheomalacia.

Symptomatic tracheomalacia associated with congenital tracheoesophageal fistula requires active treatment. When symptoms are severe, consideration should be given for surgical correction. Aortopexy via a lateral thoracotomy and tracheopexy via an anterior cervical approach have been described. We present two patients with extensive tracheomalacia who benefited from combined tracheoaortopexy via a midline sternotomy approach.

Cartilage Diseases↗

PubMed1991

Severe subaortic stenosis in interrupted aortic arch in infancy and childhood.

Thirteen out of a total 50 infants with interrupted aortic arch (IAA) seen between 1979-1988 had or developed severe subaortic stenosis (SAS). One had type A interruption and 12 type B. All had a large ventricular septal defect (VSD). The infundibular septum was displaced posteriorly in eight infants, severely narrowing the left ventricular outflow tract (LVOT). Three had fibromuscular narrowing of the LVOT, one each a subaortic muscle bar and membrane. The aortic root and subaortic area were small and measured between 3-8 mm. An anomalous right subclavian artery was noted in eight of the 12 type B IAA, the anomalous vessel arising from the descending aorta in seven. Thirteen infants with IAA and SAS were submitted to surgery, 12 having their subaortic area resected with three perioperative deaths early in the series and three late deaths where active treatment was ceased, including one infant with renal dysplasia who had had a successful establishment of arch continuity and pulmonary artery banding. Of the seven survivors, six have residual Doppler gradients of between 20-50 mmHg, two requiring a second resection and one a third resection. Alternate management programs are suggested based on anatomical evaluation and echocardiography. Any newborn presenting with IAA requires careful evaluation of the subaortic area, best seen on cross-sectional echocardiography. The improved surgical survival in infants following complete repair of IAA has led this important associated anomaly of subaortic stenosis to assume greater importance as a cause of mortality and long-term morbidity.

Anastomosis, Surgical↗

PubMed1990

Critical aortic stenosis in the first month of life: surgical results in 26 infants.

Between 1980 and 1989, 26 infants aged less than 1 month underwent open aortic valvotomy for critical aortic stenosis. All had congestive heart failure requiring inotropic agents (58%), ventilation (42%), and/or prostaglandin E1 (35%) preoperatively. Nine patients with isolated aortic stenosis had an operative mortality of 0%, whereas 17 patients with other anatomical lesions had a 47% mortality (p less than 0.01). Univariate analysis failed to identify additional risk factors other than year of operation (p less than 0.05). There were four late deaths, three probably related to arrhythmia (actuarial survival at 113 months = 0.53). Two patients have required late reoperation; neither required valve replacement.

Actuarial Analysis↗

PubMed1990

Repair of truncus arteriosus and interrupted aortic arch.

A total of seven patients with truncus arteriosus and interrupted aortic arch (IAA) comprises our surgical experience in this condition. All underwent primary complete repair via median sternotomy between June 1985 and December 1989. Median age at repair was 8 days and median weight, 3.2 kg. Anatomy of these seven patients was truncus arteriosus type "1 1/2" in five patients and type II in two patients, IAA type B in six patients and type A in one patient. Aortic arch was reconstructed by direct anastomosis of ascending aorta and descending aorta. Right ventricle to pulmonary artery continuity was established with a porcine valved conduit in four patients, aortic homograft in two, and aortic homograft monocusp patch in one. Three patients have required five reoperations (three in one patient). One reoperation was due to compression of the left main bronchus from the reconstructed aorta, one was due to obstruction of the aorta at the site of IAA repair, and one was due to compression of the left main bronchus, right pulmonary artery, and residual stenosis across the hypoplastic ascending aorta. There were no early or late deaths and all seven survivors are currently well with a mean follow-up of 29 months from initial repair.

Anastomosis, Surgical↗

PubMed1990

Two-patch repair of complete atrioventricular septal defect in the first year of life. Results and sequential assessment of atrioventricular valve function.

Before January 1987, 62 infants underwent two-patch repair of complete (51) or intermediate (11) atrioventricular septal defect at the Royal Children's Hospital, Melbourne. Median age at repair was 4.3 months and median weight was 4.4 kg. Early deaths (3%) were confined to two infants with preoperative respiratory tract infections; a further two patients died during follow-up (late mortality rate 3%). Reoperation for severe postoperative mitral regurgitation was necessary in 10 infants (16%), two of whom subsequently required mitral valve replacement with a prosthesis. Preoperative atrioventricular valve regurgitation was assessed retrospectively in 49 patients from angiography or Doppler echocardiography and was found to be absent or mild in 33 (68%), moderate in 9 (18%), and severe in 7 (14%). At the time of latest review (at a mean of 2.4 years after repair), judged from a combination of clinical and echocardiographic criteria, mitral regurgitation was absent or mild in 49 (84%) of the 58 survivors; none of them had symptomatic regurgitation or were requiring continuing medical treatment. Analysis of sequential atrioventricular valve function in 46 of the 49 patients in whom objective preoperative data were available showed no relationship between the degree of preoperative and postoperative atrioventricular valve regurgitation. Infants without Down's syndrome, however, had a significantly higher reoperation rate for severe postoperative mitral valve regurgitation (50%) than those with Down's syndrome (10%) (p = 0.007). Complete atrioventricular septal defect can be repaired in early infancy with a low mortality rate and good intermediate term results.

Female↗

PubMed1989

Total anomalous pulmonary venous drainage.

Forty-four patients with total anomalous pulmonary venous drainage underwent repair between 1979 and 1987. The anomalous drainage was supracardiac in 16, cardiac in 12, and infracardiac in 16. Median age at repair was 15 days and median weight, 3.3 kg. In 22 patients (50%) the venous drainage was obstructed. Emergency operation was necessary in 12 patients, and the condition of seven additional patients deteriorated while they were awaiting semiurgent operation. There was one hospital death (mortality rate 2.3%), occurring in a 2-week-old premature neonate with infracardiac drainage. In 17 of 44 patients, mean pulmonary artery pressure equaled or exceeded systemic arterial pressure immediately after repair. Four patients have required reoperation and two of these have died as a result of peripheral extension of pulmonary vein sclerosis. In the review period of from 1 month to 7 years, all survivors are well and receiving no medication.

Angiography↗

PubMed1988

Effects of vasodilators on rates of change of nasopharyngeal temperature and systemic vascular resistance during cardiopulmonary bypass in anaesthetized dogs.

The effects of various vasodilating agents on the rates of change of nasopharyngeal temperature and total systemic vascular resistance of anaesthetized dogs during cardiopulmonary bypass were studied. Intravenous administration of nitroglycerine (14 micrograms/kg per min, infused at 35 degrees C and 36 degrees C), sodium nitroprusside (5 micrograms/kg per min, infused at 36 degrees C) and phenoxybenzamine (1 mg/kg bolus, given at 32 degrees C and 36 degrees C) did not have any effect on the total cooling time or the rate of cooling from 36 degrees C to 18 degrees C. However, in dogs treated with phenoxybenzamine the time taken to rewarm to 36 degrees C was significantly shorter than those observed in the control, nitroglycerine or sodium nitroprusside treated animals. This difference in rewarming time was mainly due to the more even rate of rewarming induced by phenoxybenzamine. Moreover, a significantly greater reduction in systemic vascular resistance was observed in phenoxybenzamine treated animals than in the other treatment groups.

Anesthesia↗