Catherine Bull

Fate Of Subpulmonary Homograft Conduits: Determinants Of Latehomograft Failure

PATIENTS AND METHODSnBetween 1971 and 1993, 656 conduits were placed in the subpulmonary position. Patients receiving heterografts or valveless conduits and patients dying within 90 days of insertion were excluded; thus 405 homograft conduits were studied. There were 293 aortic homografts, 94 pulmonary, and 18 of unknown type. The end point of conduit failure was defined by conduit replacement for whatever reason, balloon dilation of the conduit, or death of the patient with the conduit in place. The following factors were analyzed: aortic versus pulmonary homograft, antibiotic preservation versus cryopreservation, ABO and Rh compatibility, type of material used for conduit extension, age at operation, size of the conduit, diagnosis, and reoperations. Conduit number (1 to 405) in the series was included in the multivariable model.nnnRESULTSnFirst conduits and conduits inserted earlier in the series appeared to last longer than second and subsequent conduits and those inserted later in the series (p = 0.001 and 0.003, respectively). Overall survival of conduits at 5, 10, and 15 years was 84% (95% CL, 80% to 88%), 58% (95% CL, 50% to 66%), and 31% (95% CL, 19% to 43%). Corresponding figures for the first conduits were 88% (95% CL, 84% to 92%), 65% (95% CL, 56% to 73%), and 34% (95% CL, 20% to 47%). The longest surviving homograft conduit in our series lasted 22.7 years. Regarded univariately, reoperation (redo worse), order number (recent worse), type of conduit (pulmonary worse than aortic), preservation (cryopreserved worse than antibiotic preserved), and age at operation (older patients worse) were statistically significant. However, in multivariable analysis, including all the above in the model, only reoperation and order number had significant predictive power. When patient survival was considered, patients operated on more recently survived longer despite the fact that their conduits were being replaced earlier. Overall, survival of patients at 5 and 15 years was 95% (95% CL, 93% to 98%) and 85% (95% CL, 77% to 92%), respectively.nnnCONCLUSIONSnPulmonary and aortic homografts, both cryopreserved and preserved in nutrient antibiotic solution, give similar results. All conduits will probably have to be replaced during the lifetime of the patient. In view of the worse performance of replacement conduits, techniques of repair that avoid the use of conduits should be further explored. Despite gradual deterioration of homograft conduits, they remain an important tool in the correction of many complex lesions with excellent 15-year patient survival.

Pulmonary atresia and intact ventricular septum: a revised classification.

The dismal outlook for patients with pulmonary atresia with intact ventricular septum may be related to associated right ventricular hypoplasia. Study of 32 autopsy specimens and 46 angiocardiograms of neonates with this lesion suggested that the cavitary hypoplasia was related to massive hypertrophy of the right ventricular wall. This hypertrophy was sufficient to obliterate the trabecular and/or infundibular portion of the ventricular cavity entirely in one‐third of the cases; this observation forms the basis for a revised classification of these hearts. Three autopsies and 14 angiograms of neonates with critical pulmonary stenosis were examined. Hearts with obliterated infundibular and trabecular cavities had thicker walls and smaller tricuspid valves, as estimated angiographically or at autopsy, than those in which the normal three portions of the ventricular cavity were represented.

Pulmonary atresia and intact ventricular septum: surgical management based on a revised classification.

Sixty patients with pulmonary atresia and intact ventricular septum (PA:IVS) presenting from 1970 to 1980 are reviewed. Three groups of patient are discussed: those with tripartite right ventricles, those with no trabecular portion to the cavity, and those with neither trabecular nor infundibular portions. The decrease in early mortality for neonates with PA:IVS since 1977 (one death in 15 patients) supports our current management policy of preoperative prostaglandin El infusion with transpulmonary valvotomy (for patients with an infundibular cavity) combined with a left modified Blalock‐Taussig shunt using a Gore‐Tex prosthesis. Tricuspid valve growth, estimated by serial angiograms in 12 patients, was greater if right ventricle‐to‐pulmonary artery continuity was established. Later definitive repair was attempted in nine patients, with two early deaths; five underwent right ventricular outflow tract reconstruction and four had modified Fontan procedures. Neonates with critical pulmonary stenosis are also discussed. Their neonatal mortality (nine deaths in 20 patients) was similar to that of comparable patients with PA:IVS, but their actuarial survival at 5 years (55%) was superior (36% at 5 years).

Impact of Fontan operation on left ventricular size and contractility in tricuspid atresia.

Left ventricular dimensions and contractility were determined by echocardiography in 33 patients with tricuspid atresia in 1985 and again in 1988. Eight patients remained palliated throughout the 3-year period; neither the left ventricular end-diastolic diameter (153 +/- 15% of normal vs. 157 +/- 19%, p = NS) nor a load-independent index of contractility (rate-corrected velocity of shortening [VCFc]/end-systolic meridional stress [ESSM]) changed. Eleven patients underwent a Fontan operation during the study and were reevaluated at least 6 months after surgery; left ventricular dimension decreased (130 +/- 15% vs. 114 +/- 19%, p less than 0.001), and the contractility index VCFc/ESSM improved (p less than 0.05). Fourteen patients had undergone a Fontan operation 0.9-9.5 years (mean, 4.2 years) before initial examination in 1985. Over the 3-year period, left ventricular dimensions did not change (121 +/- 17% vs. 118 +/- 11%, p = NS), but the contractility index showed significant improvement (p less than 0.01). Eight additional patients were studied just before and after a Fontan operation to examine the early effects of surgery. Left ventricular dimensions decreased from 130 +/- 14% to 100 +/- 13% by 10 days p less than 0.001) with no further change at 2 months. An inappropriate degree of ventricular hypertrophy was observed in only the early postoperative period. Successful Fontan repair results in rapid reduction of left ventricular size, followed by regression of hypertrophy to a normal mass-to-volume ratio. Operating at more favorable dimensions and loading conditions results in an early increase in left ventricular contractility, which further improves in the medium term follow-up.

Percutaneous balloon valvuloplasty for pulmonary valve stenosis in infants and children.

Pulmonary valve stenosis was relieved by balloon dilatation during cardiac catheterisation on 27 occasions in 23 infants and children aged 7 days to 12 years, median 31 months (three aged less than 2 weeks). Pulmonary valve diameter was estimated by cross sectional echocardiography to assist in the choice of balloon size. Before dilatation the right ventricular systolic pressure ranged from 41 to 190 (median 92) mm Hg and was suprasystemic in 10 patients. There were significant reductions in the ratio of right ventricular to systemic systolic pressure and pulmonary systolic pressure gradients immediately after balloon dilatation. Twelve patients underwent recatheterisation (11 at six months and one at one week after balloon dilatation), which showed further improvement with significant reductions in right ventricular pressure or pulmonary valve gradient or both, particularly in the patients with the least satisfactory initial results. This improvement was attributed to resolution of the obstruction at infundibular level. Repeat pulmonary valve dilatation was successfully performed in four patients who had poor results after initial dilatation. Balloon pulmonary valvotomy appears to provide good short term and medium term relief of pulmonary valve stenosis and may obviate the need for surgery in many cases. An apparently poor immediate haemodynamic result does not preclude a good longer term result.

Percutaneous balloon dilatation of aortic valve stenosis in neonates and infants.

Percutaneous balloon dilatation of severe aortic valve stenosis was attempted in thirteen patients (seven neonates and six infants). In two the valve could not be crossed and both died during subsequent operation. Two patients died during manipulation of the balloon catheter. No significant benefit was obtained in another patient who later died during operation. Balloon dilatation was successful in the remaining eight patients, reducing the aortic valve pressure gradient from a mean of 63 mmHg (95% confidence interval 38 to 88 mmHg) to a mean of 23 mmHg (95% confidence interval 7 to 39 mmHg). Two of these patients subsequently died from heart failure related to other cardiac lesions. The six survivors have done well. At follow up the maximum Doppler velocities in the ascending aorta ranged from 1.9 to 4.0 m/s after 2-23 months, but despite this evidence of an increasing valve gradient there has been lasting clinical improvement.

Correction of isolated secundum atrial septal defect in infancy.

Although it is a common congenital cardiac lesion, secundum atrial septal defect (ASD) rarely presents in infancy. Its natural history in the first two decades of life is generally benign. Reports of symptomatic ASD in early childhood stress the place of conservative management, and recommend that the operation should be deferred until school age. Few accounts of the indications for surgery in infancy exist. We present our experience of 6 patients who failed to respond adequately to conservative treatment and required operation for intractable heart failure due to isolated secundum ASD in the first year of life. As their presentation and physical signs were not typical of ASD seen in later childhood, they presented problems both of diagnosis and management.

Balloon dilatation of the aortic valve for congenital aortic stenosis in childhood.

Balloon dilatation of the aortic valve was attempted in 34 consecutive children aged 16 months to 17 years (median 7 years), weight range 9-60 (median 22) kg. Previous surgical valvotomy had been performed in two patients (twice in one of them). The valve was not crossed in one patient. In the remaining 33 patients the pressure difference between the left ventricle and the ascending aorta during systole was reduced from 71 (30) to 28 (19) mm Hg. In 24 patients recatheterisation 2-19 (mean 9) months later showed gradients that were similar to those immediately after balloon dilatation (35 (20) v 31 (20) mm Hg). The two patients with the highest residual gradients immediately after balloon dilatation showed a spontaneous reduction in gradient at repeat catheterisation, whereas the patient who had twice had previous surgical valvotomy showed an increase in gradient from 37 to 99 mm Hg over nine months and required aortic root replacement. Balloon dilatation was repeated in two patients and this caused a further reduction in gradient. New aortic regurgitation occurred in nine (27%) patients (grade I, 8; grade II, 1) and aortic regurgitation was exacerbated (grade I to II) in two of the nine with pre-existing aortic regurgitation. External iliac artery avulsion occurred in one (3%) patient and two (6%) required intravenous streptokinase because the femoral artery became occluded. There were no other complications. Open valvotomy was performed in the child in whom the valve was not crossed, but no other child required aortic valve operation. Balloon dilatation of the aortic valve gave reasonable short term palliation and was well tolerated. It is an alternative to surgical valvotomy for initial palliation of congenital aortic stenosis in many children.

Formalin infiltration of ductus arteriosus in cyanotic congenital heart disease.

Formalin infiltration of the ductus arteriosus was performed in 13 neonates with pulmonary atresia (three with ventricular septal defect, two with tricuspid atresia, and eight with intact ventricular septum, one of whom had Ebsteins anomaly) in an attempt to maintain duct patency. Nine patients had an additional retrograde pulmonary valvotomy and one a Blalock-Taussig shunt. The mean preoperative systemic PO2 was 31 mmHg and rose significantly to 46 mmHg after operation. However, the PO2 rose in only two of the four patients who had formalin infiltration alone. There were five early deaths and three had clinical evidence of duct closure. Four patients needed further surgery (systemic-pulmonary artery shunt) within eight days. Seven of eight surviving patients were shown to have a closed duct at repeat cardiac catheterisation (two to 13 months after operation). The eighth died before restudy. There were four late deaths, one following late reoperation and the other three within five months of early reoperation. These results suggest that formalin infiltration cannot ensure long-term duct patency. As short-term patency can be maintained more reliably by prostaglandin administration, we have abandoned the operation.

I was so worried about every drop of milk - feeding problems at home are a significant concern for parents after major heart surgery in infancy.

Abstract Increasing numbers of operations in small infants with complex congenital heart disease are being carried out in the UK year on year, with more surviving the initial operation. However, even after successful surgery some of these infants remain fragile when they are discharged home. The aim of the study was to elicit parents experiences of caring for a child with complex needs after major congenital heart surgery. We conducted a qualitative study involving semi‐structured interviews with parents of 20 children (aged <1–5 months at hospital discharge), who had undergone open heart surgery and subsequently died or been readmitted unexpectedly to intensive care following their initial discharge home. Feeding difficulties following discharge from the specialist surgical centre emerged as one of the most significant parental concerns spontaneously raised in interviews. For some parents the impact of feeding difficulties overshadowed any other cardiac concerns. Key themes centred around feeding management (particularly the practical challenges of feeding their baby), the emotional impact of feeding for parents and the support parents received or needed after discharge with respect to feeding. Caring for a child with congenital heart disease following surgery is demanding, with feeding difficulties being one of the most significant parent stressors. Local health professionals can be a good source of support for parents provided that they are well informed about the needs of a cardiac baby and have realistic expectations of weight gain. Specialist surgical centres should consider addressing issues of parental stress around feeding and weight gain prior to hospital discharge.