Hepatic fibrosis and cirrhosis in the Fontan circulation: a detailed morphological study.

AIMS: To describe the histological features of the liver in patients with a Fontan circulation. METHODS: Specimens from liver biopsies carried out as part of preoperative assessment prior to extracardiac cavopulmonary conversion of an older style Fontan were examined and scored semi-quantitatively for pertinent histological features. To support the use of the scoring, biopsy specimens were also ranked by eye for severity to allow correlation with assigned scores. RESULTS: Liver biopsy specimens from 18 patients with a Fontan circulation were assessed. All specimens showed sinusoidal fibrosis. In 17 cases there was at least fibrous spur formation, with 14 showing bridging fibrosis and 2 showing frank cirrhosis. In 17 cases at least some of the dense or sinusoidal fibrosis was orcein positive, although a larger proportion of the dense fibrous bands were orcein positive compared with the sinusoidal component. All specimens showed marked sinusoidal dilatation, and 14 showed bile ductular proliferation; 1 showed minimal iron deposition, and 1 showed mild lobular lymphocytic inflammation. There was no cholestasis or evidence of hepatocellular damage. Similar appearances were observed in 2 patients with severe tricuspid regurgitation. DISCUSSION: The histological features of the liver in patients with a Fontan circulation are similar to those described in cardiac sclerosis. Sinusoidal dilatation and sinusoidal fibrosis are marked in the Fontan series. The presence of a significant amount of orcein negative sinusoidal fibrosis suggests there may be a remediable component, although the dense fibrous bands are predominantly orcein positive, suggesting chronicity and permanence. No inflammation or hepatocellular damage is evident, suggesting that fibrosis may be mediated by a non-inflammatory mechanism.

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.

Acquired combined immunodeficiency associated with protein losing enteropathy complicating Fontan operation.

It is vitally important that the immunological aspect of protein losing enteropathy following Fontan procedures is highlighted, in order to decrease significant morbidity and mortality

Safe retrieval of impacted central venous line.

Embolisation of impacted central venous lines is not uncommon in paediatric practice. We describe a method of preventing this complication and associated risks.

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.

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.

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.

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.

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.

Intrapulmonary arteriovenous shunting may be a universal phenomenon in patients with the superior cavopulmonary anastomosis: a radionuclide study.

OBJECTIVE: To evaluate the extent of intrapulmonary right to left shunting in children after bidirectional cavopulmonary anastomosis (BCPA). DESIGN: Prospective study of patients who underwent BCPA in a single centre. PATIENTS: 17 patients with complex cyanotic congenital cardiac malformations who underwent BCPA at 1-45 months of age (median 21 months) were evaluated 15-64 months postoperatively (median 32 months). Five children between 1 and 10 years (median 5 years) with normal or surgically corrected intracardiac anatomy and peripheral pulmonary circulation who required V/Q scanning for other reasons were used as controls. INTERVENTIONS: All patients underwent cardiac catheterisation to exclude angiographically demonstrable venovenous collaterals followed by pulmonary perfusion scanning using (99m)technetium ((99m)Tc) labelled albumen microspheres to quantify the intrapulmonary right to left shunt. MAIN OUTCOME MEASURE: Percentage of intrapulmonary right to left shunt. RESULTS: The mean (SD) level of physiological right to left shunting found in the control group was 5.4 (2.3)%. All patients with BCPA showed the presence of a significantly higher level of intrapulmonary shunting (26.8 (16.9)%, p < 0.001). The degree of shunting was significantly increased in the subgroup of 11 patients with BCPA as the only source of pulmonary blood flow (34.9 (15.8)%), when compared to the six remaining patients with an additional source of pulmonary blood supply (12.0 (2.6)%, p < 0.001). There was a negative correlation between age at BCPA and the shunt percentage found in the patients with a competitive source of pulmonary blood flow (r = -0.63, p < 0. 01). CONCLUSIONS: Intrapulmonary right to left shunting develops in all patients following BCPA. This may be caused by a sustained and inappropriate vasodilatation resulting from absence or decreased levels of a substance that inhibits pulmonary vasodilatation. Augmenting BCPA with an additional source of blood flow containing hepatic factor limits the degree of intrapulmonary arteriovenous shunting and may help provide successful longer term palliation.

Diagnosis, management, and pathophysiology of post-Fontan hypoxaemia secondary to Glenn shunt related pulmonary arteriovenous malformation.

An 8 year old child with tricuspid atresia had developed right sided pulmonary arteriovenous malformations following a previous classic Glenn procedure. These became clinically manifest immediately after Fontan conversion because of severe systemic desaturation. The pathophysiology and postoperative medical management of this case is described and related to current understanding of the aetiology of acquired pulmonary arteriovenous malformations following cavopulmonary shunt.

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.

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.

Induced hypothermia in the postoperative management of refractory cardiac failure following paediatric cardiac surgery.

Postoperative low cardiac output states are a major cause of postoperative mortality in infants and children following corrective cardiac surgery for congenital heart defects. In this unit, whole body hypothermia has been used since 1979 in the management of these low output states when they are refractory to conventional modes of therapy. Twenty cases treated in this way between July 1986 and June 1990 were reviewed in 1992. The current report reviews the 50 further cases treated with moderate hypothermia between July 1990 and December 1995. The median (range) age of patients was 8 months (0 days-16 years) with a median weight of 4.1 kg (2.5-33 kg). Following cooling, there was a decrease in heart rate (p < 0.001), an increase in mean arterial pressure (p < 0.001) and a decrease in mean atrial pressure (p < 0.001). Significant increases in pH and urine output were also noticed, the increase in urine output being greater in the surviving group (p = 0.02). A decrease in platelet count occurred (p < 0.001) but white blood cell count remained unchanged (p = 0.18). Twenty-five of the 50 patients survived to leave hospital. Induced hypothermia does not appear to be associated with any complications and after the failure of all conventional treatment, it seems likely that the technique may have been beneficial to outcome in some patients.

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.