Electrophysiological mapping and ablation of intra-atrial reentry tachycardia after Fontan surgery with the use of a noncontact mapping system.

BACKGROUND: Atrial tachyarrhythmias are a complication of Fontan surgery. Conventional electrophysiological mapping and ablation techniques are limited by the complex anatomic and surgical substrate and a high arrhythmia recurrence rate. This study investigates the use of noncontact mapping to identify arrhythmia circuits and guide ablation in Fontan patients. METHODS AND RESULTS: Eleven arrhythmias were recorded in 6 patients. Noncontact mapping improved recognition of the anatomic and surgical substrate and identified exit sites from zones of slow conduction in all clinical arrhythmias. Radiofrequency linear lesions were targeted across these critical zones in 5 patients. One patient underwent surgical cryotherapy. Although immediate success was achieved in 3 of 5 patients with radiofrequency ablation, 2 patients had a recurrence after a mean of 6.4 months of follow-up. The patient who underwent cryoablation remains free of arrhythmias. CONCLUSIONS: Noncontact mapping can identify arrhythmia circuits in the Fontan atrium and guide placement of ablation lesions. Arrhythmia recurrence is high, possibly because of inadequate lesion creation rather than inaccurate mapping and lesion targeting.

The failing Fontan circulation: successful conversion of atriopulmonary connections.

OBJECTIVES: Symptoms from low cardiac output or refractory atrial arrhythmias are complicating atriopulmonary (classical) Fontan connections. We present our experience of converting such patients to total cavopulmonary connections with and without arrhythmia surgery. METHODS: Between 1997 and 2002, 15 patients (mean age, 19.7 +/- 7.0 years) underwent conversion operations 12.7 +/- 3.5 years after atriopulmonary Fontan operations. Preoperative New York Heart Association functional class was I in 2 patients, II in 2 patients, III in 6 patients, and IV in 5 patients. Four patients underwent intracardiac lateral tunnel conversion alone, and 11 received extracardiac total cavopulmonary connection, right atrial reduction, and cryoablation. RESULTS: No mortality occurred. One patient had conduit obstruction in the immediate postoperative period requiring replacement, and another required a redo operation for endocarditis. Average hospitalization was 17.9 +/- 9.38 days; chest drains were removed on median day 4 (range, 1-29; mean, 7.4 +/- 7.58 days). At follow-up (mean, 42.6 +/- 22.1 months), late atrial arrhythmias had recurred in 3 of 4 patients with intracardiac total cavopulmonary connections (without ablation) and 1 of 11 patients with extracardiac total cavopulmonary connections with ablation. All patients are in New York Heart Association class I or II. Exercise ability (Bruce protocol) improved 69% from a mean of 6.18 +/- 4.01 minutes to 10.45 +/- 2.11 minutes (P <.05). Need for antiarrhythmic agents decreased postoperatively (patients receiving < or =1 antiarrhythmic: 9 preoperatively vs 15 at long-term follow-up, P <.05). No patient has required transplantation. Protein-losing enteropathy, which was present in 1 patient, improved transiently with conversion. There was 1 late death from gastrointestinal hemorrhage. CONCLUSIONS: Fontan conversion can be achieved with low mortality and improvement in New York Heart Association class and exercise ability. Concomitant arrhythmia surgery reduces the incidence of late arrhythmias.

Repair of truncus arteriosus in early infancy with antibiotic sterilized aortic homografts.

BACKGROUND: To evaluate the fate of the truncal valve, the antibiotic sterilized aortic homografts, and the survival after repair of truncus arteriosus in the first 6 months of life. METHODS: Between 1974 and 1994, 23 infants (mean age 1.7 months, range 5 days to 6 months) underwent primary repair of truncus arteriosus by one surgeon (J.L.M). Sixteen were neonates (age range 5 to 30 days). Continuity between the right ventricle and the pulmonary artery was established with an aortic antibiotic sterilized homograft (mean diameter 14.9 mm, range 11 to 17 mm). Follow-up was 100% complete. RESULTS: Four neonates with severe truncal regurgitation died early (17.4%). Fourteen patients underwent reoperations. Five had a truncal valve replacement (mean time 7 years, range 6 months to 17 years). Ten-year freedom from truncal valve replacement was 78.2%. Eleven patients had homograft replacement (mean time 12.7 years, range 2 to 26.2 years). Ten-year freedom from homograft replacement for any cause was 77.1% (for homograft-related problems it was 86.7%). Seven patients retained the original homografts (mean time 14.3 years, range 6 to 18.7 years). There was one late death. Overall 10-year survival was 79% and for the hospital survivors it was 95%. All survivors are in New York Heart Association functional class I. CONCLUSIONS: Abnormal truncal valves pose serious early and late problems but the patients with normal truncal valves do well and seem unlikely to need replacement of these valves. The durability of the antibiotic sterilized aortic homograft even in sizes less than 14 mm is remarkably good. Late survival is excellent.

A rare cause of profound cyanosis after Kawashima modification of bidirectional cavopulmonary anastomosis.

The expected level of systemic arterial saturation may not be present after bidirectional superior cavopulmonary anastomosis in children with complex congenital cardiac anomalies. We present a case of persistent severe cyanosis in a patient with azygos continuation of the inferior vena cava after bidirectional superior cavopulmonary anastomosis (Kawashima procedure) due to an intrahepatic venovenous malformation. Subsequent transcatheter deployment of two Rashkind double umbrella devices into the malformation reduced the shunt and markedly improved systemic arterial saturation.

Growth potential in the new aortic arch after non-end-to-end repair of aortic arch interruption in infancy.

BACKGROUND: Complete repair of infants with interrupted arch and ventricular septal defect through a midline incision has been the preferred method for more than 20 years. End-to-end anastomosis can result in restenosis if there is excess tension. Two methods of reducing this tension have been described, and the subsequent growth of the new aortic arch is demonstrated. METHODS: In 2 infants (5 and 9 months old) the duct was used to create a new aortic arch. In 3 other younger infants the left carotid artery was divided, turned down, and anastomosed to the descending aorta to form the new arch. These operations were performed through the midline at the same time as the ventricular septal defect was closed. RESULTS: All 5 patients are well now 8 to 19 years postoperatively. One patient required reoperation for stenosis at the anastomotic site, but all have subsequently shown good growth on follow-up angiographic and magnetic resonance imaging studies. CONCLUSIONS: Although end-to-end repair is best, these alternative methods have shown very satisfactory aortic growth into adult life.

Open commissurotomy for critical isolated aortic stenosis in neonates.

BACKGROUND: The optimal management of critical aortic stenosis in early infancy remains controversial. The aim of this study was to assess the early and late outcomes following open surgical valvotomy for critical aortic stenosis in neonates and to provide a framework of data against which current results of other treatment approaches can be evaluated. METHODS: Eighteen consecutive neonates (mean age 9.2 days, range 1 to 26 days) undergoing an open valvotomy for critical isolated aortic stenosis (the standard treatment for this condition in our unit) between 1984 and 2000 were studied. The mean aortic valve gradient was 79.4 mm Hg. Twelve neonates received prostaglandins and 10 received inotropic agents preoperatively. Follow-up was complete (mean 8.1 years, range 1 month to 15 years). RESULTS: There was no operative mortality. At discharge, the mean aortic valve gradient was 37.2 mm Hg, with 6 patients having mild and 2 having moderate aortic regurgitation. Six patients required a reoperation; 3 of these had an aortic valve replacement at 9 to 11 years of age. Kaplan-Meier 5- and 10-year freedoms from any aortic reoperation or reintervention were 85 and 55%, respectively; 5- and 10-year freedoms from aortic valve replacement were 100 and 79%, respectively. A 14-year-old boy died from endocarditis 4 years following an aortic valve replacement in another unit. Kaplan-Meier 10-year survival was 100%. All survivors are in New York Heart Association I class and are leading normal lives. Their mean aortic valve gradient is 34.5 mm Hg, and none has significant aortic regurgitation. CONCLUSIONS: Open valvotomy for critical aortic stenosis in neonates carries a low operative risk and provides lengthy freedom from recurrent stenosis or regurgitation. Reoperations are inevitable, but aortic valve replacement can be delayed until the implantation of an adult-sized prosthesis is possible. Late survival is excellent. We consider open surgical valvotomy to be the treatment of choice for critical neonatal aortic stenosis.

Outcome after repair of tetralogy of Fallot in the first year of life.

BACKGROUND: The purpose of this study was to evaluate the early and late outcome after repair of tetralogy of Fallot in the first year of life. METHODS: Between 1974 and 2000, 89 consecutive infants with a mean age of 6.3 +/- 2.6 months (range, 15 days to 12 months) underwent repair of tetralogy of Fallot (ventricular septal defect and pulmonary stenosis) by one surgeon (J.L.M.). Three infants had previous palliative operations. Sixty-seven procedures were urgent or emergency. A transannular patch was inserted in 69 patients (77.5%). Follow-up was complete, averaging 13.4 +/- 5.6 years (range, 0 to 25.4 years). RESULTS: There was one operative death (1.1%). Mean right ventricular to left ventricular pressure ratio postoperatively was 0.4 +/- 1.1 (in 79 patients, < 0.5). Fourteen patients underwent reoperations or reinterventions. There were no reoperations for residual or recurrent ventricular septal defect. Kaplan-Meier freedom from reoperation or reintervention for any cause at 20 years was 85% +/- 4.4%, for relief of right ventricular outflow tract obstruction it was 94% +/- 3.1%, and for pulmonary valve replacement this was 95.4% +/- 2.6%. Use of a transannular patch did not significantly affect the need for reoperation or reintervention. There was one late death (leukemia). Kaplan-Meier 20-year survival was 97.8% +/- 1.9%. On latest echocardiography, 42 patients had moderate pulmonary regurgitation, 4 had a right ventricular outflow tract gradient more than 40 mm Hg, and 86 had good biventricular function. Twelve-lead electrocardiography was performed in all and 24-hour electrocardiography in 61 patients. One patient (1.1%) exhibited late recurrent ventricular tachycardia requiring implantation of a defibrillator. The remaining 86 patients are in New York Heart Association class I with none of them receiving antiarrhythmic medications. CONCLUSIONS: These data strongly support the concept of early repair of tetralogy of Fallot. It is associated with an acceptable operative risk and a low incidence of significant arrhythmias, and provides long-term survival similar to that observed in the general population. Late complications may, however, develop, and long-term follow-up for their early recognition is essential.

Aortic valve repair of congenital stenosis with bovine pericardium.

BACKGROUND: Conservative surgical options in the treatment of congenital aortic stenosis are limited. To relieve the obstruction necessitates full incision of the raphe of the larger valve leaflet, but this inevitably causes prolapse. METHODS: We performed aortic valve repair in 6 children, aged 14 months to 17 years, with congenital aortic stenosis, 2 having had aortic valvotomy as infants. The repair consisted of suturing the base of a triangular piece of bovine pericardium, with a simple vertical fold, to the free edges of the incised raphe. The pericardial fold was then sutured vertically to the aortic wall. RESULTS: At follow-up of 2 to 60 months, the mean peak systolic Doppler gradients had decreased from 80 +/- 15 mm Hg to 26 +/- 9 mm Hg. The effective valvular orifice area increased from 33% +/- 6% to 64% +/- 3%, allowing blood flow to increase by a factor of 3.76. Two patients have mild and 2 have mild-to-moderate aortic regurgitation. CONCLUSIONS: The described conservative repair renders the valve tricuspid and trisinusoidal, and the deficient interleaflet triangle is recreated, preventing cusp prolapse. Longer follow-up is required to assess the durability of unstented pericardium in the aortic position, but the early results are encouraging.

Bidirectional superior cavopulmonary anastomosis: how young is too young?

OBJECTIVE: To define the lowest age at which the bidirectional superior cavopulmonary anastomosis can safely be used in infants with complex congenital heart defects. DESIGN: A retrospective analysis of clinical, echocardiographic, haemodynamic, and angiographic data in four consecutive patients undergoing bidirectional superior cavopulmonary anastomosis below the age of 2 months. PATIENTS: Between November 1990 and September 1993, four infants less than 8 weeks of age (3, 4, 6, and 7 weeks) underwent bidirectional superior cavopulmonary anastomosis as a primary palliation for complex heart disease. The indication for early surgical intervention was progression of cyanosis (n = 3) and high pulmonary blood flow causing heart failure (n = 1). In two infants with tricuspid atresia, surgery was performed through a right thoracotomy without the use of cardiopulmonary bypass. In one infant with double inlet left ventricle and discordant ventriculoarterial connection, cavopulmonary anastomosis was combined with an arterial switch procedure. The final infant had double inlet left ventricle with pulmonary atresia; the central pulmonary arteries were virtually discontinuous and each branch was supplied by a separate arterial duct. The central pulmonary arteries were reconstructed using the subaortic innominate vein. Temporary prostacyclin infusion was used in three patients in the immediate postoperative period. RESULTS: Early postoperative extubation (5, 7, and 48 h) was successful in three patients. The youngest child required ligation of the ductus arteriosus four days later because of severe upper body oedema. The postoperative course was complicated by prolonged effusions in two patients. All were alive and well 14-48 months postoperatively, with satisfactory systemic saturations (80-87%) and haemodynamic indices. CONCLUSIONS: This limited experience challenges the widely held belief that the bidirectional superior cavopulmonary anastomosis cannot be used as a primary palliation for complex heart disease in early infancy. A wider experience is required to determine the safety and indications for this approach.

Haemochromatosis presenting as severe cardiac failure in a young adolescent.

A 13-year-old girl, who presented almost moribund in severe heart failure, was shown to have haemochromatosis. Repeated venesection has led to return of normal cardiac function. This adolescent would appear to be the youngest patient described with haemochromatosis whose initial presentation was that of congestive cardiac failure.

Use of larger sized aortic homograft conduits in right ventricular outflow tract reconstruction.

Between 1973 and 1993 sixty aortic homograft valved conduits in fifty-six patients were used to establish continuity between the right ventricle and the pulmonary artery in congenital heart disease. Age range was one day to 23.5 years (median 3.6 years) which included twenty-six patients less than one-year-old. Conduit size ranged from 11 to 23 mm (median 17.6 mm). there were nine hospital deaths and eight late deaths. The 45 survivors have been followed for a median of 8.6 years (range 6 months to 20 years). All patients have had serial echocardiographic assessments and 35 have had post repair cardiac catheterization. Almost all patients had mild-to-moderate degrees of homograft regurgitation. There were eleven with severe homograft regurgitation and two are being considered for reoperation. The follow up homograft gradient ranged from 0 to 64 mmHg (mean 24 mmHg). Freedom from reoperation for conduit obstruction was 98.2% at five years falling to 91% (C.L. 82%-100%) at 10 years. Of the 23 homografts inserted more than 10 years ago, only one (4.3%) has been replaced because it was causing important obstruction. None have been replaced for regurgitation. Our results indicate that larger sized aortic homografts used in reconstruction of the right ventricular outflow tract give satisfactory results and there is a low incidence of reoperation for replacement at medium term follow up.

Unusual left atrial mass following cardiac surgery in an infant.

An unexpected left atrial mass was found during routine postoperative transthoracic echocardiogram in an infant following surgical closure of ventricular septal defect. Thrombus could not be excluded. At reoperation it was found to be an inverted left atrial appendage. This case demonstrates the echocardiographic appearance of an inverted left atrial appendage.

The outcome of antibiotic sterilised aortic homografts used in the Fontan procedure.

Between 1977 and 1988, 27 patients between the ages of 4 and 22 years (mean 8.9) underwent a Fontan procedure with the use of an antibiotic sterilised aortic homograft. There were 15 patients with tricuspid atresia, 9 with univentricular heart and 3 others. The homograft was anastomosed to a right-sided pulmonary artery in ten, to a left-sided main pulmonary artery in eight and in nine patients the homograft connected the right atrium to the right ventricle. There were five early deaths (18.5%) unrelated to the homograft and two late deaths at 7 and 10 years postoperatively. Five patients have required removal of the calcified obstructed homograft with no death. In three patients patches were inserted, but in two patients with good right ventricles a second homograft was inserted. In three of the re-operated patients the homograft lay directly behind the sternum and the femoral artery was exposed and in two of them the femoral artery was cannulated before the chest was opened to control haemorrhage. Of the patients 74% are alive up to 15 years later, 15 with their original homograft. Eight (57%) of those still have their original homograft more than 10 years post-operatively.

The fate of antibiotic sterilized aortic allografts in Fontan circulation: results of the long-term follow-up.

OBJECTIVE: Between 1977 and 1988, 27 patients, mean age 8.9 (range 4-22) received an antibiotic sterilised aortic allograft in the setting of the Fontan procedure. This study describes the long-term follow-up of these patients. METHODS: Fifteen patients had tricuspid atresia, nine double inlet ventricles and three others. The connection with the allograft was made to the pulmonary artery on the right side of the aorta in ten and to a left-sided main pulmonary artery in eight. In nine patients the allograft was anastomosed between the right atrium and the right ventricle. RESULTS: There were five early and five late deaths. One late death may have been allograft related. Survival was 81, 74 and 68% at 5, 10 and 15 years, respectively. Conduit calcification was universal. Twelve patients underwent reoperation, freedom from reoperation was 100, 88 and 54% at 5, 10 and 15 years following the initial Fontan procedure. At reoperation the gradient across the allograft was never more than 3 mmHg. The allograft was explanted with conversion to atriopulmonary or cavopulmonary connection in nine and a second allograft was inserted between the right atrium and right ventricle in two. No mortality occurred at reoperation. 41.1% of survivors still have their original allograft. CONCLUSIONS: Although there is a significant attrition rate allograft inclusion in the Fontan circulation does not change survival, but results in an increased reoperation rate. Inclusion of a valved conduit between the right atrium and ventricle does not usually enhance the growth potential of the rudimentary ventricle. All patients are in a good functional class which may represent the strict original selection criteria. The inclusion of a valve in the Fontan circulation is not recommended.

Twelve year experience with the modified Blalock-Taussig shunt in neonates.

Between 1978 and 1990, 53 consecutive modified Blalock-Taussig (MBT) shunts were performed on 51 neonates with cyanotic congenital heart disease using 3 mm-5 mm Gore-Tex grafts. Only 4 of these children had uncomplicated tetralogy of Fallot. The remainder had more complicated pathology requiring urgent intervention. Retrospective analysis of the acute and long term results was performed with 100% follow-up, ranging from 1 month to 12 years (mean 3 years). There were 3 (6%) early deaths (within 30 days of operation) and 17 (33%) late deaths. Of the late deaths, 2 died after further palliation, 2 died after total correction and 13 died suddenly at home. Post mortem examination of the 13 sudden deaths revealed blocked shunts in only 3. Actuarial survival at 2 years was 58%. Shunt patency at 12 months was 87% and at 2 years, 62%. No patient used their initial MBT shunt for more than 40 months. Although this shunt provides good initial palliation, there is a high incidence of late sudden death. We are also concerned about the limited life span of the shunt which partly (3/13) explains the sudden deaths. Therefore we have adopted an aggressive approach to re-study by angiography within 3 months of surgery.

Is there still a place for open surgical valvotomy in the management of aortic stenosis in children? The view from Southampton.

OBJECTIVE: The most appropriate management of aortic stenosis (AS) in children remains controversial. The purpose of this study was to determine the outcome following open valvotomy for AS in children. METHODS: Ninety-seven consecutive, unselected, children (mean age 3.2 +/- 3.6 years, 1 day--15 years) underwent an open valvotomy for critical (n=36) or severe (n=61) AS between 1979 and 2000 in Southampton. Twenty-six were neonates (1--31 days), 27 were infants (1--12 months) and 44 were older children (1--15 years). Mean follow-up was 10 +/- 5.4 years, 1 month--21.9 years. RESULTS: Two neonates died early giving an overall operative mortality of 2.1% (7.7% for the neonates and 0% for infants and older children). The mean aortic gradient was reduced from 76 to 24.5 mmHg (P < 0.0001). Residual or recurrent AS occurred in 17 patients and severe aortic regurgitation in eight patients. Kaplan--Meier 10-year freedom from residual or recurrent AS was 83.1 +/- 4.7% and from severe aortic regurgitation was 95.3 +/- 2.7%. Twenty-five patients required an aortic re-operation or re-intervention, 18 of whom had an aortic valve replacement (AVR) (mean valve size 21.8 +/- 0.9 mm, range 21--25 mm). Ten-year freedom from any aortic re-operation or re-intervention was 78.4 +/- 5.2% and from AVR was 85.1 +/- 4.6%. There were ten late deaths. Overall 10-year survival, including hospital mortality, was 90.2 +/- 3.1% (69.7 +/- 9.7% for the neonates, 92 +/- 5.4% for the infants and 100% for older children, (P < 0.0001). Ten-year survival for children with isolated AS (n = 69) was 100% and for those with associated cardiovascular problems (n = 28) was 67.3 +/- 8.9% (P < 0.0001). All survivors are in New York Heart Association functional class I. CONCLUSIONS: Open valvotomy remains the gold standard in the management of AS in neonates, infants and older children. It is associated with low operative mortality and provides lengthy freedom from recurrent AS and regurgitation. Re-operations are common but if AVR is required, implantation of an adult-sized prosthesis is usually possible. There is a late death-hazard for those with severe associated lesions, but the survival prospects for the patients with isolated AS are excellent.

Cavopulmonary anastomosis as long-term palliation for patients with tricuspid atresia.

Prior to 1970, most patients with tricuspid atresia (TA) and reduced pulmonary blood flow were palliated by means of a systemic to pulmonary artery shunt (SPAS). In Birmingham between 1967 and 1988, 19 patients with TA (aged 16 days to 23 years, mean 3.8 years) have undergone side-to-side cavopulmonary anastomosis (CPA) with preservation of pulmonary artery continuity. One had undergone a previous right Blalock-Taussig shunt and in 1 patient with left and right SVCs, bilateral CPAs were performed. Nine patients were less than 1 year old at the time of operation. There were no operative deaths. One late death occurred due to pneumonia. Immediate clinical improvement occurred in all cases. Six symptomatic patients subsequently required further surgery (mean interval between operations 8.9 years, range 4.6-14.2 years). The remaining 12 patients have recently been reviewed. Mean follow-up was 9.5 years (range 5 weeks to 21 years). Exercise tolerance remains good (9 in NY-HA Class 1 or 2) and resting transcutaneous oxygen saturations are higher (mean 85%, range 70%-89%) compared with preoperative values (P less than 0.01). In small children, CPA avoids the complications of SPAS and, in some patients, may itself achieve adequate long-term definitive palliation.

Mitral valve replacement with mechanical prostheses in children: improved operative risk and survival.

OBJECTIVE: The purpose of this study was to assess the early and late outcome following mitral valve replacement (MVR) with mechanical prostheses in children. PATIENTS AND METHODS: Between 1981 and 2000, 44 consecutive children (mean age 6.8+/-4.7 years, 2 months--16 years) underwent mechanical MVR in Southampton. Twenty-three children were less than 5-years-old and nine were infants. Disease aetiology was congenital in 37, rheumatic in four, infective in two and Marfan's syndrome in one. Mitral regurgitation was present in 36 and mitral stenosis in eight. Concomitant procedures were performed in 13, including aortic valve replacement (AVR) in seven. Follow-up was complete (mean 6.4+/-4.8 years, 1 month--18.1 years). RESULTS: The overall operative mortality was 14% (six patients). Before and after 1990 operative mortality was 31 vs 3.6% (P=0.02). From 1990, operative mortality for infants was zero out of six, for children less than 5-years-old was one out of 16 (one death after emergency AVR and MVR) and for older children it was 0/12. Seven children experienced valve or anticoagulation treatment-related events and eight had a mitral valve re-operation. Ten-year freedom from thromboembolism, prosthetic valve infection, bleeding, paravalvular leak and a mitral valve re-operation was 92.8+/-5.2, 97.3+/-2.7, 97.7+/-2.3, 97.2+/-2.7 and 75+/-9.7%, respectively. Overall 10-year survival was 78+/-7% (four late deaths); for children under vs over 5 years it was 61+/-11 vs 95.2+/-4.6% (P=0.02), for atrio-ventricular septal defect (AVSD) vs other pathology 55+/-15 vs 89+/-6.1% (P=0.05) and for those operated before 1990 vs after 1990 it was 63+/-8.1 vs 86+/-8.2% (P=0.04). CONCLUSIONS: Mechanical MVR, in the current era, carries a low operative risk across the spectrum of paediatric age. Late survival is better for older children and those having no-AVSD pathology but it has improved substantially during the 1990s irrespective of age and disease aetiology.

Pulmonary artery banding is not contraindicated in double inlet left ventricle with transposition and aortic arch obstruction.

It has been widely stated that pulmonary artery banding (PAB) is contraindicated in the setting of double inlet left ventricle with transposition of the great vessels (DILV/TGA), especially if aortic arch obstruction is present. We postulated that the poor results for this condition reflect the tendency to leave the band in place long-term without early recognition and relief of subaortic stenosis (SAS). Short-term PAB with early relief of SAS remains an attractive option compared to a neonatal "Norwood" strategy. We reviewed our results applying this approach to 18 consecutive infants presenting since 1980 with DILV/TGA and an obstructive anomaly of the aortic arch (coarctation 16, interruption or atresia 2). Four of the infants (22%) were considered to have important SAS at presentation. One underwent neonatal aortopulmonary connection and died. The remaining 17 patients underwent arch repair with PAB (median age 1.4 weeks; range 2 days-22 weeks) with one early death. The 16 survivors have been followed for 5.6 +/- 3.7 years. All but one ultimately developed SAS. Relief of SAS was performed in 15 patients (median age 8 months) using a proximal aortopulmonary anastomosis. There were two early deaths, and one late death. Thirteen of the 18 patients (72%) are alive and well, and 12 have achieved Fontan repair or bidirectional superior cavopulmonary anastomosis (BCPA) with persistent relief of SAS. Most patients with DILV/TGA and aortic arch obstruction will tolerate temporary PAB with adequate protection of the pulmonary vascular bed. Our current approach (in the absence of severe SAS at presentation) is PAB at the time of arch repair, followed by careful surveillance for, and early relief of, SAS combined with BCPA in infancy.

Induced hypothermia as salvage treatment for refractory cardiac failure following paediatric cardiac surgery.

OBJECTIVE: Following corrective cardiac surgery in infants and children for congenital heart disease, a persistent low cardiac output refractory to conventional modes of treatment is associated with a mortality approaching 100%. We advocate the use of whole body hypothermia to reduce tissue oxygen demand and provide a degree of cellular protection against ischaemia allowing time for recovery. We describe our experience. METHODS: Between July 1986 and December 1995, 1885 infants and children underwent surgery (operative mortality, 6%), 1302 requiring cardiopulmonary bypass. Fifty-seven patients had a persistent low cardiac output, impaired respiratory function, decreased urine output and acidosis despite maximal intensive care treatment. Cooling to 32-33 degrees C was therefore started using a thermostatically controlled water filled cooling blanket. RESULTS: Following cooling, there was a fall in heart rate (P<0.001), a rise in mean arterial pressure (P<0.001) and a fall in mean atrial pressure (P<0.001). Significant (P<0.001) increases in pH and urine output were also recorded. Thirty-one (54%) of the 57 patients treated with cooling survived to leave hospital. No long-term sequelae have been noted in these patients. CONCLUSION: Induced hypothermia is a useful salvage treatment, in children following corrective cardiac surgery when all conventional treatment has been tried and failed.