Bidirectional cavopulmonary shunts: clinical applications as staged or definitive palliation

A standard Glenn anastomosis between the superior vena cava and the right pulmonary artery has been the accepted mode of treatment for patients with complex cyanotic congenital heart disease. We report our experience in 18 patients with such disease who underwent a bidirectional cavopulmonary shunt because of increasing cyanosis and growth cessation. All patients were considered less than "ideal" candidates for a Fontan procedure. We divided the patients into two groups: group 1 had azygos continuation and group 2 did not. Fourteen patients required hypothermic cardiopulmonary bypass. Bidirectional pulmonary blood flow was achieved in all patients. Only 1 death occurred (group 2). The improvement in oxygen saturation and overall clinical condition of these patients, together with the low mortality and morbidity, is encouraging. However, long-term follow-up is mandatory for a comprehensive evaluation of this surgical approach as definitive palliation or as a first stage for a Fontan operation.

Cardiac surgery for grown-up congenital heart patients: survey of 307 consecutive operations from 1991 to 1994

The cardiac surgery performed from 1991 to 1994 in a unit dedicated specifically for grown-up congenital heart (GUCH) patients was reviewed to determine the frequency of various procedures, incidence of first and reoperations, early mortality, and its determinants. The 295 patients, aged 16 to 77 years (31 +/- 13), had 307 operations. First operations (n = 128, 42%) were most commonly for closure of atrial septal defect (n = 40), aortic valve replacement (n = 31) or repair of aortic coarctation (n = 14). Reoperations were more frequent (n = 179, 58%) and divided among first corrective repair (n = 49), reoperation after corrective repair (n = 115), and further palliation (n = 15). First corrective surgery was mainly for aortic valve disease (n = 17), Fallot (n = 7), and lesions needing a Fontan procedure (n = 5). Reoperations after corrective repair were needed for aortic valve disease (n = 43), right-sided conduit (n = 30), or recoarctation (n = 11). Early mortality was influenced by presence of central cyanosis (9 of 49, 18% in cyanotic patients; 12 of 258, 5% in acyanotic; p <0.001), increased number of previous operations (0 = 4%, 1 = 7%, 2 = 11%, >2 = 13%; p = 0.003), and increasing age of patients. Cyanotic patients had more serious postoperative complications: pleural and pericardial effusions, severe bleeding, renal insufficiency, and sepsis, and their hospital stay was longer compared with acyanotic patients (20 +/- 17 vs 11 +/- 8 days; p <0.001). In GUCH patients, reoperations cause the largest demand on cardiac surgical services. Increased survival of patients with complex cardiovascular malformations brings difficult challenges not only to cardiologists but also to cardiovascular surgeons. There is a need to provide continued highly specialized care. Resources, patients, and funding should be concentrated in a few designated centers.

Determinants of neuropsychological and behavioural outcomes in early childhood survivors of congenital heart disease

AIMS

To evaluate the relative effect of cyanosis, surgical interventions and family processes on neuropsychological and behavioural outcomes in 4-year-old survivors of serious congenital heart disease (CHD).

METHODS

90 children with a range of cyanotic and acyanotic conditions, who underwent either corrective or palliative surgery, completed a neuropsychological and behavioural evaluation. Families of participants were also profiled by evaluation of maternal mental health, worry, social support, parenting style and family functioning.

RESULTS

Compromised neuropsychological outcomes were associated with a combination of cyanotic conditions and open-heart surgery, but this was not exacerbated by having a complex, palliative, status. Both cyanotic and acyanotic conditions were associated with specific sensorimotor delays, regardless of method of the correction. Only children with complex conditions and palliative interventions seemed at risk of poor behavioural outcomes; indeed, children with cyanosis with complete repair showed favourable behavioural outcomes compared with controls. Multivariate analyses highlighted the sometimes greater relevance of family processes (eg parenting style, maternal mental health and worry), rather than disease or surgical factors, in predicting especially behavioural outcomes.

CONCLUSIONS

The findings (1) suggest a more complex relationship between cyanosis, surgical methods of correction, neuropsychological and behavioural outcomes than previously charted, (2) highlight that family processes may be aetiologically more important than disease and surgical factors, and (3) indicate specific targets for secondary prevention programmes for this at-risk population.

Impact of cyanotic heart disease on school performance

Surgical correction greatly decreases the mortality and cardiac morbidity of cyanotic congenital heart disease, but children remain at risk of long term difficulties in other areas. A historical cohort study was conducted to determine the relation between heart disease and school performance in 29 children aged 7 to 12 years old with simple transposition of the great arteries or tetralogy of Fallot. All children had surgical correction of their lesion before 2.5 years of age. Those at greater risk of school difficulties because of recognised complications of their heart disease or for reasons other than directly attributable to the heart disease were excluded. Comparison was made with 36 children who had presented with cardiac murmurs at a similar age, but who did not require treatment. Children with cyanotic disease showed significantly poorer performance in all academic areas assessed by the Wide Range Achievement Test-Revised; the difference in group mean score (adjusted for differences in maternal education, sex, and parental occupational prestige) for reading was 10.3 points (confidence interval (CI) 1.25 to 19.34), for spelling 7.8 (CI 1.11 to 14.52), and for arithmetic 6.8 (CI 0.19 to 13.39). The differences in adjusted group means for the Wechsler Intelligence Scale for Children-Revised full scale, performance and verbal IQs were significant, particularly the later at 10.1 points (CI 2.59 to 17.61). Teacher reports indicated significant differences in arithmetic when outcome was dichotomised to 'below grade' or 'not below grade'. There were no significant associations between outcome measures and the medical or perioperative parameters, however, including those related to hypoxia. It is concluded that the increased incidence of academic problems and the nature of the cognitive difficulties in children with uncomplicated corrective cardiac surgery for cyanotic heart disease are not fully explained by chronic hypoxia, or by other factors related to the cardiac surgery.

Intrapulmonary shunting in the biliary atresia/polysplenia syndrome: reversal after liver transplantation

One hundred and seventy three children, including 93 with biliary atresia, received liver grafts at Addenbrooke's Hospital between 1983 and 1993. Of these, only seven developed cyanosis due to intrapulmonary shunting as a complication of their liver disease, and all seven of these had the biliary atresia/polysplenia syndrome. Intrapulmonary shunting was confirmed by a radioisotope scan in four children. Only one child with the syndrome did not have cyanosis when undergoing transplantation. Seven of the eight children are alive 6-54 months after transplantation, with normal pulmonary and hepatic function. Cyanosis recurred in one child who developed chronic rejection with liver failure.

IN CONCLUSION

(a) there is a strong association between the biliary atresia/polysplenia syndrome and cyanosis due to intrapulmonary shunting; (b) intrapulmonary shunting is fully reversible after successful liver transplantation; and (c) cyanosis, once present, is progressive, and these children should be considered for liver transplantation as soon as it occurs.

Cyanotic congenital heart disease and coronary artery atherogenesis

Hypoxemic erythrocytotic residents of high altitudes lack coronary atherosclerosis and have low cholesterol levels. It was postulated that hypoxemic erythrocytotic adults with cyanotic congenital heart disease (CCHD) might be analogous. The incidence of coronary atherosclerosis in this patient population has not been established, and hypocholesterolemia has not previously been recognized. Accordingly, 279 patients were divided into 4 groups: group A: 143 cyanotic patients not operated on (54 men and 89 women, aged 18 to 69 years); group B: 47 cyanotic patients (28 men and 19 women rendered acyanotic by operation at age 22 to 69 years); group C: 41 acyanotic patients not operated on (22 men and 19 women, aged 22 to 75 years); and group D: 48 patients acyanotic before and after operation (24 men and 24 women, aged 21 to 70 years). Coronary arteries were studied angiographically in 59 patients and at necropsy in 5 subjects aged 37 to 56 years. Total cholesterol was <160 mg/dl in 58% of group A, 52% of group B, 10% of group C, and 12% of group D (p <0.000001, chi-square analysis). Angiograms disclosed dilated coronary arteries without obstruction. Necropsy disclosed ectatic coronary arteries with structural abnormalities of the media. In conclusion, this study provides the first quantitative and qualitative data on antiatherogenic changes in lipoproteins in adults with CCHD. The coronary arteries are atheroma free because hypocholesterolemia acts in concert with the antiatherogenic properties of upregulated nitric oxide, hyperbilirubinemia, hypoxemia, and low platelet counts. The persistence of hypocholesterolemia after the surgical elimination of cyanosis suggests a genetic determinant.

The influence of pH strategy on cerebral and collateral circulation during hypothermic cardiopulmonary bypass in cyanotic patients with heart disease: results of a randomized trial and real-time monitoring

OBJECTIVE

The optimal pH strategy during hypothermic cardiopulmonary bypass remains controversial. Systemic pulmonary collateral circulation may develop in patients with cyanotic anomalies. The purpose of this study was to evaluate the effect of pH strategies on cerebral oxygenation and systemic pulmonary collateral circulation during hypothermic cardiopulmonary bypass in cyanotic patients with heart disease.

METHODS

Forty cyanotic patients (age > 1 year) with heart disease were prospectively randomized into 2 groups. Group 1 (n = 19, 14.3 +/- 1.5 kg) underwent hypothermic cardiopulmonary bypass with alpha-stat strategy and group 2 (n = 21, 12.5 +/- 0.9 kg) with pH-stat. Cardiopulmonary bypass was established with pump-assisted drainage. Cerebral oxygenation was assessed by near-infrared spectroscopy and the systemic pulmonary collateral circulation was calculated by pump flows [% systemic pulmonary collateral circulation = perfusion flow - drainage flow)/perfusion flow x 100]. Lactate was measured as an index of systemic anaerobic metabolism.

RESULTS

There were no significant differences in preoperative hematocrit, oxygen saturation, Qp/Qs, cardiopulmonary bypass duration, minimum temperatures, perfusion flow and pressure, urine output, and depth of anesthesia between the groups. Oxyhemoglobin signal and tissue oxygenation index of near-infrared spectroscopy monitoring were significantly lower in group 1 compared with group 2 (P =.008 and P <.0001, respectively), suggesting inadequate cerebral oxygenation with alpha-stat. Deoxygenated hemoglobin signal was significantly higher in group 1 relative to group 2 (P <.0001). The % systemic pulmonary collateral circulation was significantly lower in group 2 compared with group 1, suggesting a reduced pulmonary collateral circulation with pH-stat (P <.0001, average; group 1, 20.1% +/- 1.2%; group 2; 7.7% +/- 0.7%). Serum lactate was significantly lower in group 2 (P <.0001).

CONCLUSIONS

The pH-stat strategy results in an improved environment, including sufficient cerebral oxygenation, decreased systemic pulmonary collateral circulation, and lower lactate level during hypothermic cardiopulmonary bypass in cyanotic patients with heart disease. Future studies should investigate the long-term neurological outcome.

A detailed histologic analysis of pulmonary arteriovenous malformations in children with cyanotic congenital heart disease

INTRODUCTION

Pulmonary arteriovenous malformations are a common cause of progressive cyanosis in children after cavopulmonary anastomoses. We analyzed the pulmonary histologic characteristics from children in whom pulmonary arteriovenous malformations developed after procedures that resulted in pulmonary arterial blood flow devoid of hepatic venous effluent.

METHODS

We performed routine histologic studies, immunohistochemical staining, and electron microscopic analysis of peripheral lung biopsy specimens from 2 children with angiographically proven pulmonary arteriovenous malformations. Microvessel density was determined with a computer-assisted, morphometric analysis system.

RESULTS

Histologic examination demonstrated large, dilated blood vessels ("lakes") and clustered, smaller vessels ("chains") in the pulmonary parenchyma. Microvessel density was significantly greater in these patients than in age-matched controls (P =.01). Immunohistochemistry demonstrated uniform staining for type IV collagen and alpha-smooth muscle actin, weak staining for the endothelial marker CD31 (cluster of differentiation, PECAM-1), and negative staining for proliferating cell nuclear antigen. Electron microscopy revealed endothelial irregularity, a disorganized basement membrane, and increased numbers of collagen and actin filaments beneath the endothelium.

CONCLUSIONS

This study represents an attempt to characterize the histologic features of pulmonary arteriovenous malformations in children with congenital heart disease who have pulmonary arterial blood flow devoid of hepatic venous effluent. The histologic correlate of this condition appears to be greatly increased numbers of thin-walled vessels. Immunohistochemistry suggests that the rate of cellular proliferation is not increased in these lesions. The development of these techniques may provide a standardized histologic approach for this condition and aid in understanding its etiology.

Ascending aorta-right pulmonary artery shunt in infants and older patients with certain types of cyanotic congenital heart disease

A side-to-side anastomosis between the ascending aorta and the right pulmonary artery was created in 80 infants (less than 1 year of age) and in 61 older children with a variety of cyanotic cardiac abnormalities in which there is pulmonary stenosis or atresia. Seventy-one per cent of the infant group and 90% of patients over 1 year of age were long-term survivors (up to 6 years).

Tetralogy of Fallot was the most commonly encountered anomaly in all 141 patients (66%); transposition of the great vessels and pulmonary stenosis occurred in 18%; and tricuspid atresia with pulmonary stenosis in 10%.

The presence of an excessively large shunt anastomosis (55% of deaths) and additional (unrecognized) other anomalies (26%) were major causes of postoperative deaths.

In patients in whom a systemic-pulmonary artery anastomosis is required, this operation is the procedure of choice in infants under 1 year of age. It is also of value in older patients if a Blalock-Taussig shunt cannot be performed.

Tricuspid annuloplasty and ventricular plication for Ebstein's malformation

BACKGROUND

Seven patients with the diagnosis of Ebstein's malformation of the tricuspid valve were operated on. Mean age was 12 years (range, 7 to 16 years). All were cyanotic, with severe tricuspid regurgitation. Thromboembolism was not present. No associated cardiac malformations were present.

METHODS

Surgical repair included tricuspid annuloplasty associated with longitudinal plication of the atrialized portion of the right ventricle. This was attained by approximating the anterior-posterior commissure with either the posterior-septal commissure or the septal leaflet remnant. The thin atrialized ventricular wall thus excluded remained as a cul du sac and was plicated by suturing along the longitudinal axis of the heart. When present, the dysplastic posterior leaflet was included in the plication. In essence, a monocuspid right atrioventricular valve was fashioned out of the anterior leaflet. The remaining septal leaflet played a minimal functional role. No additional procedures for treatment of arrhythmia were associated with the technique described.

RESULTS

The postoperative course was uneventful in all patients. Mean follow-up is 4.3 years (range, 1 to 10 years). Doppler echocardiographic studies reveal satisfactory monocusp valve function in all patients, with adequate coaptation of the anterior leaflet and the septal structures.

CONCLUSIONS

This technique seems applicable to most forms of Ebstein's malformation and is reproducible. The technique relies on the adequate mobilization of the anterior leaflet. Occasionally it is necessary to free fibrous adhesions of the leaflet to the underlying ventricular surface.

Arterial thrombosis and protein S deficiency

A previously healthy boy had progressive painful discoloration of the lower extremities and was treated with exchange transfusion and anticoagulation, which were unsuccessful in arresting pedal ischemia; amputation of all of the child's toes was required. Studies of the patient and his parents resulted in a diagnosis of inherited protein S deficiency.

Cardiac tamponade in a newborn because of umbilical venous catheterization: is correct position safe?

Cardiac tamponade is a rare but life-threatening complication of umbilical venous catheterization in the newborn. Most complications from central venous catheters are related to incorrect position of the catheter and it is emphasized to confirm the position of the catheter tip after placement in order to avoid possible complications. We present an unusual complication of cardiac tamponade because of umbilical venous catheterization in a term newborn which is extremely rare with correct location of the catheter tip at the junction of inferior vena cava and right atrium. We suggest that correct position never guarantees uneventful catheterization in the newborn. In any infant with a central venous catheter in situ who deteriorates clinically, pericardial effusion/cardiac tamponade must be considered and appropriate action taken.

Effects of hemodilution on outcome after modified Blalock-Taussig shunt operation in children with cyanotic congenital heart disease

OBJECTIVE

Cyanotic congenital heart diseases (CCHD) with secondary polycythemia and hyperviscosity state are associated with a reduction in blood flow, stagnation of blood, and thrombosis. Sufficient hemodilution in cyanotic children results in higher blood flow and significant reductions in perioperative blood loss. The aim of this study was to investigate similar beneficial effects of hemodilution in preventing shunt thrombosis and decreasing postoperative blood loss after modified Blalock-Taussig (BT) shunt operations in children with CCHD.

DESIGN

Prospective, randomized, controlled study.

SETTING

Cardiac center of a tertiary care, referral hospital.

PARTICIPANTS

Fifty children with CCHD undergoing modified BT shunt operations.

INTERVENTIONS

Patients were randomized into 2 groups. The study group (n = 25) received a calculated amount of 6% hydroxyethyl starch (200/0.5) solution to bring down the hematocrit to 45%, whereas the control group (n = 25) received 5% dextrose solution intraoperatively as per the authors' normal protocol.

MEASUREMENTS AND MAIN RESULTS

Effects of hemodilution on shunt patency, postoperative blood loss at 24 hours, blood and blood component usage, and re-exploration rates were recorded. The shunt patency rate was significantly higher in the study group than the control group (100% and 84%, respectively, p < 0.05). Postoperative blood loss at 24 hours was significantly higher in the control group than in the study group (14.4 +/- 11.8 mL/kg and 9.9 +/- 8 mL/kg, respectively, p < 0.05). The number of recipients and the amount of blood and blood components administered were higher in the control group, but they were not statistically significant. The re-exploration rate (for excessive postoperative chest-tube drainage) was significantly higher in the control group than the study group (12% and 0%, respectively, p < 0.05).

CONCLUSION

Hemodilution in CCHD patients undergoing modified BT shunt surgery has beneficial effects including improved shunt patency because of higher blood flow through the graft and less postoperative blood loss, which may be attributed to the lower viscosity produced by hemodilution.

Use of self expanding stents in stenotic aortopulmonary shunts in adults with complex cyanotic heart disease

OBJECTIVE

To describe the use of self expanding stents in treating long segment stenosis of aortopulmonary shunts (APS) in adults.

DESIGN

Clinical records, catheterisation data, cineangiograms, and operation notes of four consecutive patients undergoing stent implantation since December 1994 were studied retrospectively.

SETTING

A tertiary referral centre for cardiac disease.

SUBJECTS

Four patients underwent cardiac catheterisation because of clinical deterioration. Their age ranged between 23 and 32 years. The underlying diagnosis was complex cyanotic heart disease in all. Three had a stenotic interposition graft, and one had a classic Blalock shunt.

RESULTS

There was one technical failure owing to migration of the stent distal to an ostial stenosis. The ability index, resting oxygen saturation, and exercise tolerance improved in the remainder. Their medium term results have been excellent.

CONCLUSIONS

This technique may further palliate adult patients with complex congenital heart disease, though the long term patency of stents is unknown.

Indications for the Brock operation in current treatment of tetralogy of Fallot

It is now generally accepted that a certain proportion of children with severe tetralogy of Fallot are anatomically unsuitable for one-stage total correction of the anomaly. The choice of the best preliminary operation for these is still in some doubt, however. Following Brock's original hypothesis that relief of the outflow obstruction will encourage enlargement of the main pulmonary artery and annulus (and therefore favour subsequent successful total correction) we have preferred this procedure in all cases not suitable for immediate total correction. In a consecutive series of 36 cases the results have been found to be very acceptable and to compare favourably with those obtained with anastomotic procedures such as the Blalock or Waterston shunt. The operation has been accomplished with an 11% mortality, and in 72% of cases cyanosis has been abolished under conditions of normal exercise. Sixteen cases have subsequently come to total correction with a 25% mortality and a 75% `cure' rate. In the light of this experience we find that closed pulmonary valvotomy with or without infundibular resection has a definite and valuable place in the current treatment of Fallot's tetralogy. General and specific indications for its use are presented.

Dynamics of factor XIII levels after open heart surgery for congenital heart defects: do cyanotic and acyanotic patients differ?

Cardiopulmonary bypass (CPB) reduces coagulation factor levels through hemodilution and consumption. Differences in CPB-induced alterations of factor XIII (FXIII) levels in children with cyanotic and acyanotic congenital heart defects (CHDs) are not well characterized. FXIII activity (determined by Berichrom assay), prothrombin index, activated partial thromboplastin time, and fibrinogen were measured before open heart surgery with CPB and 5 days postoperatively for children older than 3 years with acyanotic (n = 30) and cyanotic (n = 30) CHDs. The preoperative FXIII levels did not differ significantly among the children of the compared groups. The cyanotic patients showed a significantly longer duration of CPB (111.4 ± 45.8 vs 71.5 ± 33.6 min; p = 0.026) and aortic cross-clamp (68.0 ± 27.1 vs 45.4 ± 31.4 min; p = 0.034). The drop in FXIII levels after termination of CPB was more profound for the children with cyanotic CHDs (87.1 ± 13.4 to 49.1 ± 13.2 vs 81.5 ± 12.6 to 58.6 ± 11.1 %, respectively; p = 0.018). The cyanotc patients also were restored to their baseline FXIII levels later than the children with acyanotic CHDs (at 48 vs 24 h). The post-CPB dynamics of the majority of the other coagulation parameters in the compared groups of patients were similar. The cyanotic patients experienced significantly greater postoperative blood loss than the acyanotic patients (12.6 ± 4.9 vs 5.0 ± 2.1 mL/kg; p < 0.001) and were transfused with larger volumes of red blood cells (10.4 ± 6.5 vs 4.2 ± 2.5 mL/kg; p = 0.007). The decrease in FXIII levels after CPB is more profound and lasts longer in children with cyanotic CHDs than in acyanotic patients. The rational strategy of postoperative FXIII replacement therapy for these categories of patients needs to be determined.

Intrahepatic right-to-left shunting after the Fontan operation

We describe two patients with right isomerism, corrected with a fenestrated Fontan operation, who suffered severe progressive cyanosis. Cardiac catheterisation in both revealed a massive right-to-left shunt from the inferior caval vein, through the liver, to a hepatic vein draining directly to the left side of the intra-atrial baffle. The anomalous vein was successfully ligated in both patients.

Feasibility and safety of immediate perioperative implantation of intravascular stents in cavopulmonary pathways

Fontan-type procedures are widely used for palliation of patients with many forms of a functional univentricular heart. An ideal Fontan circuit should be free of any distortion or stenosis. The use of stents for the treatment of stenotic and hypoplastic vessels is well established in pediatric cardiac practice. We report the successful use of endovascular stents during the immediate postoperative period in patients undergoing cavopulmonary anastomoses.

Increasing cyanosis after total cavopulmonary connection treated by banding a separate liver vein

An increasing right-to-left shunt after a total cavopulmonary connection was treated by banding the separate liver vein. As a variation on a fenestrated total cavopulmonary connection, this liver vein was not connected with the intercaval tunnel. After a few days, the shunt increased to an unacceptable level. This was treated by banding the liver vein, which was connected with the right-sided atrium and turned out to be only part of the venous drainage of the liver.

Bilateral pectoral myocutaneous advancement flaps and anatomic sternal wound reconstruction in cyanotic infants with mediastinitis

OBJECTIVE

The purpose of this study was to assess the results and applicability of a modified chest closure technique employing bilateral pectoral myocutaneous advancement flaps after sternal re-approximation for postoperative mediastinitis in cyanotic infants.

METHODS

The study population is of a single surgeon's pediatric cardiac experience (n = 253) over a 2-year period. With retrospective hospital chart review six cases with deep sternal wound complications were identified (five mediastinitis and one hypoxemic wound necrosis). Sternal wound reconstruction was done with the above technique in all cases. Follow up was completed by outpatient record review and with telephone interviews.

RESULTS

All six cases presented in this paper were neonates or infants with complex cyanotic cardiac malformations. Following chest wall reconstruction all had complete resolution of their mediastinitis with no mortality and no wound healing complications. Three of them have since undergone elective staged repair, with no evidence of residual wound infection. Two babies died during follow-up as a result of progressive respiratory compromise.

CONCLUSION

For postcardiotomy mediastinitis in cyanotic infants we recommend limited debridement and anatomic sternal reconstruction supported by bilateral pectoral myocutaneous advancement flap closure.