E. D. Silove

Total anomalous pulmonary venous connection: outcome of surgical correction and management of recurrent venous obstruction

OBJECTIVE Total anomalous pulmonary venous connection (TAPVC) can be corrected with low mortality and good outcome. If complicated by pulmonary vein stenosis (PVS), either at presentation or secondary to the repair, the long-term outcome is compromised. We have evaluated an institutional experience with TAPVC, with particular regard to the evolving management of PVS. METHODS Retrospective analysis of 85 consecutive patients with non-isomeric TAPVC undergoing surgical correction over a 10-year period (1988-1997). In addition, three patients were referred to us with secondary PVS, having had their primary procedure elsewhere. Attention was focused on incidence of PVS, and strategies for management. RESULTS Median age at first operation was 33 days (range 1-533). Site of drainage was supracardiac (43/88), infracardiac (20/88), cardiac (17/88), and mixed (8/88). On presentation, 35% of patients were ventilated. Early mortality was 7% (6/85), with one late non-cardiac death. 82% of the original patients (70/85) are currently well at a median follow-up of 64 months (range 6-119). The incidence of PVS requiring intervention was 11% (9/85). Median time to PVS was 41 days. In these patients, 18 balloon angioplasties, four endovascular stent placements (in two patients), and a further 23 surgical procedures were performed. Of the nine patients undergoing re-intervention after initial surgery at our institution, five (56%) survived. Two of these have no residual obstruction and right ventricular pressure (RVP) < 50% systemic, two have unilateral obstruction and RVP < 50% systemic, and one has bilateral obstruction and RVP 80% systemic. Of the three patients referred to us with secondary PVS, two are alive and well, and one died early after the first re-operation. CONCLUSIONS Intrinsic obstruction (endocardial sclerosis or thickening) is associated with worse prognosis and earlier re-intervention than extrinsic (anatomical) obstruction. We advocate an early, aggressive approach to the management of patients with TAPVC, especially in the presence of PVS. This complication is most appropriately managed by a combination of re-operation and repeated balloon dilation.

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.

Early results of right ventricular-pulmonary artery conduits in patients under 1 year of age.

OBJECTIVES Management strategies for the repair of many complex heart defects require the implantation of a valved conduit between the right ventricle (RV) and the pulmonary artery (PA), often using aortic or pulmonary homograft valves. Their limited availability, however, has led to the development and use of new conduits. We retrospectively compared our experience with small homografts in patients of less than 1 year of age with the TissueMed bioprosthetic valved conduit. METHODS From March 1994 to November 1997 29 patients in their first year of life underwent conduit implantation for complex heart defects. These were retrospectively reviewed in order to determine the incidence of death or conduit stenosis. Seventeen patients received homografts and 12 TissueMed conduits. RESULTS Diagnoses and operative details including conduit size were similar in the two groups and in all cases complete repair of the underlying defect was carried out. Early post-operative mortality was 4/17 (23.5%) in the homograft group and 3/12 (25%) in the TissueMed group. Echo Doppler evaluation within 1 month of operation showed no right ventricular outflow tract (RVOT) obstruction in any of the survivors. In the TissueMed group 8/9 (77%) survivors have gone on to develop significant RVOT obstruction within 12 months of operation. There have been three late deaths in this group all related to severe RVOT obstruction. Two patients died during an attempt at balloon dilatation and one patient died of progressive right heart failure. Five patients had successful replacement of the TissueMed conduit. One child remains well with no evidence of RVOT obstruction. At operation to replace conduit, or at autopsy, the stenoses were related to the deposition of fibrous tissue at the anastomotic suture lines. In the homograft group none of the survivors developed RVOT obstruction during the first 12 months post-operatively. There was one late death (non-cardiac in origin) and one child is awaiting conduit replacement 40 months after initial implantation for obstruction. CONCLUSIONS The homograft is a satisfactory conduit for re-establishment of RV-PA continuity in infancy. Further work needs to be undertaken in order to elucidate the mechanisms of early graft failure in bioprosthetic conduits if these are to be a suitable alternative for RV outflow reconstruction in infants.

Repair of truncus arteriosus: a considered approach to right ventricular outflow tract reconstruction.

OBJECTIVE In repair of truncus arteriosus the accepted methods of establishing right ventricle (RV) to pulmonary artery (PA) continuity utilize an allograft or xenograft valved conduit. Alternatively, the PA confluence may be directly anastomosed to the RV with anterior patch augmentation, which may allow growth and delay or avoid subsequent RVOT obstruction. These methods of RVOT reconstruction were evaluated in infants undergoing truncus arteriosus repair. METHODS A retrospective analysis of 61 infants undergoing repair of truncus arteriosus between November 1988 and June 2000 was performed. Median age was 34 days (range 1 day to 6.4 months). The patient cohort was subdivided into two groups (1) Valved conduit group: RV to PA continuity performed with a conduit in 38 patients using allograft (28) or xenograft (10). (2) Direct anastomosis group: direct RV-PA anastomosis performed in 23 patients, augmented anteriorly with monocusp (15) or simple pericardial patch (eight). RESULTS There were eight hospital deaths (13%, 95% confidence limits 5--21%). Hospital mortality did not differ significantly between group 1 and 2 (three patients (8%) versus five patients (22%) respectively, P=0.23). By multivariate analysis, low operative weight (P=0.023), severe truncal regurgitation (P=0.022) and major coronary abnormalities (P=0.018), were independent risk factors for hospital death. Hospital survivors were followed-up from 1.3 months to 11.8 years (mean 4.2+/-3.4 years). There were eight late deaths with survival of 73+/-6% at 2 years and beyond. Survival was not influenced by method of RVOT reconstruction (Conduit versus direct RV-PA anastomosis, 2.76+/-7%, 63+/-10%, respectively, P=0.23). Freedom from surgical RVOT reintervention was 56+/-10% in group 1 and 89+/-10% in group 2 at 10 years (P=0.023). The use of a xenograft conduit was an independent risk factor for reintervention (P<0.001). CONCLUSIONS In truncus arteriosus repair, RV to PA continuity established by a direct anastomosis was associated with a low incidence of surgical RVOT re-intervention. This technique has the potential for RVOT growth and may be a useful alternative when an appropriate allograft is unavailable, particularly in the neonate where the risk of pulmonary hypertension are lower.

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 Childrens 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.

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.

Recovery pattern of left ventricular dysfunction following radiofrequency ablation of incessant supraventricular tachycardia in infants and children

Objective To assess recovery pattern of left ventricular function secondary to incessant tachycardia after radiofrequency ablation in a group of infants and children. Design and setting A combined prospective and retrospective echocardiographic study carried out in a tertiary paediatric cardiac centre. Patients Echocardiographic evaluation of left ventricular size and function in nine children with incessant tachycardia, before and after successful radiofrequency ablation. Age at ablation ranged from 2 months to 12.5 years (mean 4.1 years). Recovery of left ventricular function was analysed in relation to age at ablation (group I < 18 months, group II > 18 months). Main outcome measure Ventricular recovery pattern. Results Seven of the nine children had left ventricular dysfunction; six of these also had left ventricular dilatation. All children with left ventricular dysfunction had normalisation of ejection fraction and fractional shortening; left ventricular dilatation also improved, but the improvement occurred after recovery of function. There was a shorter recovery time for left ventricular function in younger (group I) than in older children (group II) (mean (SD) 5.7 (7.2) months v 31.3 (5.2) (p < 0.002). Conclusions Tachycardia induced cardiomyopathy is reversible following curative treatment with radiofrequency. Recovery of left ventricular systolic function precedes recovery of left ventricular dilatation. Time course to recovery is shorter in younger children.

Echocardiographic screening in neonates undergoing surgery for selected gastrointestinal malformations.

To compare echocardiography with clinical examination, radiography, and electrocardiography for the detection of congenital heart defects (CHD) a four year prospective study was carried out in 166 neonates with selected congenital gastrointestinal malformations (anorectal anomaly, tracheo-oesophageal fistula, duodenal atresia, exomphalos, and gastroschisis). Routine examination and investigation detected CHD in 16 neonates. Using echocardiography CHD was diagnosed in 38 (23%) neonates of whom five had two gastrointestinal malformations: in 22/57 (39%) with a tracheo-oesophageal fistula, 10/67 (15%) with an anorectal anomaly, 4/20 (20%) with exomphalos, 6/20 (30%) with duodenal atresia, and 1/7 with gastroschisis. A significantly higher incidence of CHD in neonates with gastrointestinal malformations was diagnosed using echocardiography (23%) compared with routine examination and investigation (9%). Early diagnosis of CHD allowed a unified approach to be presented to the family.

Influence of ethnic origin on the pattern of congenital heart defects in the first year of life.

OBJECTIVE--To assess the prevalence and patterns of congenital heart defects in infants requiring hospital admission in a defined population and to determine the differences in ethnic groups. DESIGN--A three year retrospective analysis of all hospital admissions for paediatric congenital heart defects in a single centre. SETTING--Tertiary referral centre for infant cardiac services in the West Midlands region, United Kingdom. PATIENTS AND METHODS--Indian, Pakistani, Bangladeshi and other individuals from the Indian subcontinent constitute 5.8% of the total population of the West Midlands region. Some 9% of infants, however, are Asian because of a high birth rate. All infants with confirmed congenital heart defects resident in this region who required hospital admission between April 1990 and March 1993 were classified as Asians and non-Asian, mainly white, infants. RESULTS--Of 1111 infants with congenital heart defects born in the West Midlands and admitted to the hospital, 17.0% were Asian, significantly more than the percentage of Asian infants in the population (P < 0.0001). Asian infants had a higher proportion of complex congenital heart disease (7% v 2.1%, P < 0.001), whereas coarctation of the aorta was more common in non-Asian (3% v 9.1%, P = 0.003). Persistent arterial duct seemed to be more common in Asian children (16% v 10%, NS), but this group included preterm infants admitted for duct ligation. There was no significant difference between the two groups in the other nine categories of congenital heart defects. CONCLUSIONS--The estimated prevalence of congenital heart defects requiring hospital admission was higher in Asian infants than in non-Asian (9.45 per 1000 v 4.56 per 1000, P < 0.0001). Complex congenital heart defects were more common in Asian infants whereas coarctation of the aorta was more common in non-Asian.

Diagnosis of right ventricular outflow obstruction in infants by cross sectional echocardiography.

Cross sectional echocardiographic studies were assessed prospectively in 58 infants in whom right ventricular outflow obstruction was subsequently shown angiographically. A subcostal cut was used to display simultaneously the short axis of the aortic root and the long axis of the right ventricular outflow tract. This facilitated the differentiation of the common right ventricular outflow tract obstructive lesions. Tetralogy of Fallot was diagnosed correctly in 22 of 26 infants; pulmonary atresia with intact septum in all of 14 neonates; isolated severe pulmonary valve stenosis in all of nine infants; and pulmonary atresia with ventricular septal defect in eight of nine infants. The subcostal approach is the technique of choice for evaluating right ventricular outflow tract obstruction as it is more reliable than the left parasternal approach.