4D Flow analysis of intracavitary blood flow dynamics and energetics in the systemic right ventricle

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Italian Ministry of Health

Background

The systemic position of a morphologically right ventricle (SRV) makes it vulnerable to fail, leading to high incidence of heart failure and cardiac death [1]. Understanding SRV intracavitary blood flow dynamics and energetics could improve patient risk stratification.

Purpose

Testing the potential of three-dimensional time-resolved phase contrast cardiac magnetic resonance (4D Flow) in quantifying SRV blood flow dynamics and energetics.

Methods

4D Flow prototype sequences were acquired on 3 patients (1 male, 2 females) with SRV in D-loop transposition of great arteries after atrial switch operation (D-TGA/ASO), 3 male patients with SRV in L-loop TGA (L-TGA) and healthy controls (2 males, 1 female).

Kinetic energy (KE), viscous energy loss (EL), dissipation index (DI) calculated as EL to KE ratio, and hemodynamics forces (HFs) resulting from pressure gradients, were computed for the D-TGA/ASO and L-TGA SRVs, and for the control left ventricles (LVs) and right ventricles (RVs). HFs were decomposed in inferior-anterior, septal-lateral and basal-apical components (HFIA, HFSL, HFBA, respectively)

Results

Figure 1 reports the time-course of HF components and the general features of the enrolled subjects.

In systole, all SRVs (Figure 1a-1b) presented a dominant HFIA and a minor HFSL, similarly to RVs (Figure 1c); however, HFSL had a positive peak, indicating septal contraction towards the SRV cavity, opposite to its normal motion. HFBA magnitude was similar to LVs (Figure 1d), suggesting that the shortening of the tricuspid anulus towards the apex is more pronounced than in RVs (Figure 1c).

Over the whole cardiac cycle, DI values were highest in D-TGA/ASO SVRs (0.40-0.55); in L-TGA SRVs, DI values (0.24-0.45) were comparable to healthy LVs (0.22-0.37) and RVs (0.23-0.36). This difference may be related to the fact that in DTGA/ASO the left atrium is functionally replaced by a pulmonary venous baffle, which lacks efficient contraction, as highlighted by the absence of a distinctive A-wave in the KE time-course (Figure 2a).

Due to the adaptation to systemic afterload, SRVs were hypertrophic (Figure 1a-1b), with indexed mass higher than normal RVs (Figure 1c), and presented reduced compliance to the diastolic filling, as suggested by increased KE E-wave slope in L-TGA (Figure 2b) compared to controls (Figure 2c-2d).

Conclusions

Intracavitary HFs in SRVs reveal a partial shift from a RV towards LV pattern. This occurs at the expenses of a higher energetic consumption in D-TGA/ASO than L-TGA, enlightening the crucial role of atrial contribution to impaired SRV diastolic filling. These findings corroborate the previous evidence that patients with D-TGA/ASO have abnormal decrease in stroke volume during exercise whereas L-TGA patients can reach values comparably to healthy controls [2].

Body mass index stratification in hospitalized Italian adults with congenital heart disease in relation to complexity, diagnosis, sex and age

BACKGROUND AND AIMS

Adults with congenital heart disease (ACHD) are at risk of overweight and obesity, two major health problems, though underweight can be a negative prognostic factor too. Awareness of the body mass index (BMI) in ACHD is very limited. The present study describes the use and prevalence of BMI in Italian symptomatic hospitalized ACHD patients in relation to complexity by Bethesda system classification, diagnosis, sex and age.

METHODS AND RESULTS

We classified 1388 ACHD patients, aged 18-69 years, on the basis of their BMI, and compared them to the Italian reference population. In our total ACHD population we found a significantly higher prevalence of underweight compared to the Italian reference population (6.34% vs 3.20%). ACHD women were more underweight than men. Underweight decreased with age. Overweight was significantly less frequent in the total ACHD population (26.73% compared to 31.70%) in the Italian reference population. Men were more likely to be overweight than women. In statistical terms obesity was similar in the Italian reference population (10.50%) and our ACHD population (9.58%). Both overweight and obesity increased with age. Results were comparable using a diagnostic anatomical-functional classification and the Bethesda system classification.

CONCLUSIONS

In our cohort of ACHD the prevalence of underweight was double that of the Italian reference population. The prevalence of overweight was lower, while obesity was similar. Since BMI does not account for differences in body fat distribution, a future aim will be to quantify the visceral component of the adipose tissue in ACHD patients and examine their body composition in order to reflect their risk of acquired cardiovascular disease better, and either to maintain or achieve an adequate visceral component.

Late surgical treatment of tetralogy of Fallot

Aim

To study early post-operative results and follow up of patients over a year old, operated on for tetralogy of Fallot (ToF).

Methods

This retrospective analysis included 22 patients (14 male and eight female) with a mean age of 9.18 ± 6.5 years (range 13.5 months to 26 years), who underwent complete repair of ToF between April 2003 and June 2009. Data from patients’ records, pre-operative cardiac catheterisation studies, operative intervention, and pre-operative and postoperative two-dimensional echocardiographic studies were reviewed. All patients underwent complete repair including closure of ventricular septal defect (VSD). A trans-annular patch was used in 12 patients while an infundibular patch was used in 10 others. Patients were evaluated one, three, six and 12 months after surgery, and annually thereafter. The duration of follow up was from eight months to six years post surgery.

Results

Classical ToF was found in 10 patients. Twelve cases had associated anomalies: two patients with hypoplastic pulmonary artery branches, two with arterial duct malformations, and eight had proximal stenosis of the left branch of the pulmonary artery. NHYA class distribution was as follows: class I: two patients; class II: five subjects; class III: 10 patients; class IV: five subjects. The mean stay in hospital was 15 ± 7 days. Two patients (9%) died during the early post-surgical period. At a mean follow-up interval of 32 ± 9 months, all patients were asymptomatic and in NYHA class I. No late deaths occurred. In three patients, we registered isolated monomorphic ventricular extrasystoles. The right ventricle outflow tract (RVOT) pressure gradient was 29 ± 1.5 mmHg in the acute post-surgical period and it did not change significantly during follow up. The right ventricular function was defined as normal in 95% of the patients in the study and was mildly depressed in 5%.

Conclusion

Even if treated later in life, our study showed very good surgical results of patients with ToF.

Postoperative nutrition of neonates undergoing heart surgery

OBJECTIVE

Postoperative nutrition of newborns undergoing heart surgery (HS) is ill-defined. We compared the postoperative growth rates (grams/day) of neonates with congenital heart defects (CHDs) fed with their own mothers' milk (HU), a starting formula (SF; 67 kcal/100 mL), or a "preterm formula" (PF; 80 kcal/100 mL).

PATIENTS AND METHODS

We studied 122 newborns undergoing HS: 81 underwent corrective surgery (group A), and 41 palliative surgery (group B).

RESULTS

No statistically significant differences were found in the growth rate between group A and B. Moreover, in both groups, no differences in terms of growth rate between infants fed HU, SF, or PF were observed. This was also true when analyses were limited to infants undergoing HS either with or without cardiopulmonary bypass.

CONCLUSIONS

In neonates undergoing HS, human milk allowed a growth rate similar to that observed with starting formulas and "preterm formulas". This effect may depend on the particular features of human milk and its protective properties for the intestinal mucosa.

Occurrence and pattern of congenital heart diseases in a rural area of sub-Saharan Africa

Summary

The extent of congenital heart disease in Cameroon remains largely unknown. The aim of this study was to determine the occurrence and pattern of congenital heart diseases in the Cardiac Centre of St Elizabeth Catholic General Hospital, situated in a rural area of Cameroon.

Methods

Between November 2002 and November 2008, a population of 2 123 patients with suspected cardiac pathologies were consulted at St Elizabeth Catholic General Hospital referral cardiac centre. Of these patients, 292 subjects were recruited for the study, based on detection of (1) precordial murmurs and/or cardiomegaly on chest X-ray examination, or (2) congenital heart diseases on transthoracic Doppler echocardiography examination.

Results

Congenital heart diseases and inorganic murmurs were found in 95.5 and 4.5% of the patients, respectively. Congenital heart diseases included tetralogy of Fallot (26.1%), isolated ventricular septal defect (38.8%), atrioventricular cushion defect (7.3%), isolated atrial septal defect (2.8%), arterial duct cases (12.4%), common arterial trunk (1.3%), isolated stenosis of the pulmonary artery (2.6%), coarctation of the aorta (1.1%), congenital mitral valve regurgitation (1.2%), atresia of the triscupid valve (1.6%), double-outlet right ventricle (2.1%), anomalous pulmonary venous return (1.5%) and left isomerism (1.2%).

Conclusion

Our data show that there is a high occurrence of congenital heart disease in this hospital in a rural zone of sub-Saharan Africa and that isolated ventricular septal defect is the predominant pathology. Post-surgical follow up remains very challenging as many parents cannot afford their children’s medical treatment or are generally not well educated.

Pattern of cerebral ultrasound in neonatal heart surgery

AIM

No study described reliably the changes in cerebral ultrasound (CUS) findings in neonatal heart surgery. We tried to define the modifications of CUS before and after heart surgery in neonates.

PATIENTS

We studied 48 neonates with congenital heart defects were studied. Of these, 33 had correction of the malformation with cardiopulmonary bypass (CPB group); 15 underwent coarctation repair/shunting procedures (no-CPB group). Patients had CUS pre-operatively, 48-72 hours after surgery, and at discharge.

RESULTS

Pre-operative studies did not show significant differences between the groups. In CPB group, preoperatively, 6/33 infants showed echogenicity of basal ganglia and 1/33 grade I IVH. In the early postoperative evaluation, 24/33 infants had abnormal scans: increased echogenicity of basal ganglia in 24 and grade I IVH in 14. At discharge, abnormal scans persisted in 20/33 (basal ganglia echogenicity in 20, grade I IVH in 12). In the no-CPB group, preoperatively, 1/15 infant showed echogenicity of basal ganglia. In the early postoperative evaluation, 6/15 had abnormal scans: increased echogenicity of basal ganglia in 6, grade I IVH in 4. At discharge, abnormal scans persisted in 3/15.

CONCLUSIONS

CUS after neonatal heart surgery shows a definite pattern of increased echogenicity of the basal ganglia, more consistent after CPB. These changes may reflect disturbances of deep grey matter, and last 10-15 days at least.

[Surgical approach to adult with congenital heart disease]

The number of adults with congenital heart disease will inevitably increase in the near future. Recent data suggest that the number of adults with congenital heart disease, whether repaired or not, approaches the number of children with the disorder. Cardiac surgery in these patients presents major difficulties in management and technique. This especially applies to cardiac reoperation, which is one of the most frequent interventions and the most common cause of death in these patients. The present study reviews our experience with a large population of 811 consecutive patients who underwent cardiac operation or reoperation between January 2000 to December 2009 at our Institution.

[Adult with congenital heart disease: an overview]

The improvement of surgical procedures over the past 40 years has changed the medical history of the congenital heart defect. It is estimated that 85% of children with congenital heart disease now have the opportunity to reach adulthood and that this percentage will increase over the next two decades. This special issue of the Journal aims to offer a basic information on key topics of this field of cardiology not newer, but still rapidly evolving.

[Right ventricular restoration in adult patients after TOF surgery]

OBJECTIVE

Pulmonary regurgitation may cause progressive right ventricular dilatation and dysfunction in adult patients previously repaired for tetralogy of Fallot. To assess the optimal surgical timing, the impact of the right ventricular restoration with a new surgical ventriculoplasty technique is evaluated following TFO repaired adult patients with severe pulmonary regurgitation and right ventricular dilatation.

METHODS

Sixteen patients with severe pulmonary valve regurgitation (PVR) and right ventricular dilatation with RVOT aneurysm underwent right ventricular remodelling since January 2002. Each underwent preoperative evaluation by Doppler echocardiography, magnetic resonance imaging (MRI), and right ventricular myocardial acceleration during isovolumic contraction (IVC). The surgical procedure included pulmonary valve implantation and RVOT restoration achieved by removal of the aneurysm tissue, coupled with a ventriculoplasty to reduce volume, accomplished by creating a satisfactory RVOT dimension by placing with 2-0 Gortex suture to allow acceptance of a 26 Hegar dilator to avoid restriction. Nine patients had associated surgical procedures.

RESULTS

All patients survived the operative procedure and underwent a 16-month follow-up interval. A reduction of cardio thoracic index and a clinical improvement occurred in each patient. Significant reduction of RVEDV and RVESV and increased right ventricular ejection fraction was observed.

CONCLUSIONS

This preliminary database implies that the right ventricular restoration is a simple and effective procedure, and introduces a structural component that should be added in repaired TFO patients with right ventricular dilatation and underlying aneurysm or akinesia of the right ventricular outflow tract.

[Tetralogy of Fallot: evolution of medical-surgical management (part 2)]

This review is divided into two parts: the first of which traces the evolution of medical and palliative techniques; the following is a selective account of surgical concepts and procedures; the emphasis is on therapeutic developments during the last 50 years. The second part approaches the surgical corrections and tries to explain the reinterventional causes and the residual defects responsible of cardiac failure.

[Tetralogy of fallot: evolution of medical-surgical management (part 1)]

Despite Tetralogy of Fallot is a well-known cardiac congenital disease, still an important cardiovascular surgery and intensive care challenge. The following is a selective account of medical and surgical concepts and procedures; the emphasis is on therapeutic developments during the last 50 years. This review is divided into two parts: the first of which traces the evolution of medical and palliative techniques; the second part approaches the surgical corrections and try to explain the reinterventional causes and the residual defects responsible of cardiac failure.

Octreotide in the management of postoperative chylothorax

Chylothorax (KT) may be a complication of thoracic surgery. Its management is not well established and may comprise dietary interventions and surgery. The effectiveness of somatostatin and its analogues has been reported, although their mechanism(s) of action is unclear. We report our experience with octreotide in a series of patients with postoperative chylothorax. Eight patients with KT were treated with a continuous intravenous infusion of octreotide (OCT) at a starting dose of 0.5 microg/kg/hr. They were compared with four additional patients with KT who were treated according to the conventional approach. After a mean of 3.3 +/- 1.9 days of treatment, fluid discharge diminished dramatically. In all patients, fluid losses stopped by postoperative day 10.5 +/- 2.9 and chest tubes could be removed after 12.8 +/- 4.1 days. Compared to a small group of historical controls, OCT reduced significantly the total fluid losses (141.1 +/- 89.3 vs 396.7 +/- 151.0 ml/kg; p = 0.003) and the postoperative length of stay (p = 0.05). No patients in the group treated with OCT required parenteral nutrition (compared to all four of the controls; p = 0.002) and/or thoracenteses (compared to two of four controls). In postoperative KT, OCT seems to be at least as effective as the conventional approach. Furthermore, OCT may reduce total fluid losses and postoperative length of stay. This may have a beneficial effect on the risk of complications and on hospital costs.

Association of Children with Heart Disease in the World: 10-year experience

Thousands of children live in developing countries with untreated but correctable congenital heart disease (CHD), and most of them will die simple because they live in poor countries that do not have suitable medical/surgical facilities. The aim of the Association of Children with Heart Disease in the World is to support the operatory and teaching activities of a group of voluntary doctors engaged in the management of children with CHD in developing countries. Since 1992, the association has obtained 160 grants for foreign doctors who have been trained in our hospitals; performed 75 missions abroad, with more than 2150 cases evaluated and 404 cardiac operations performed; obtained millions of dollars worth of donated medical equipment; and constructed two cardiac surgery departments in Syria and Cameroon. Many efforts have been made, but much more can be done as we attain more experience and develop better coordination and collaboration between the international groups engaged in this emerging social need.

Growth after neonatal arterial switch operation for D-transposition of the great arteries

The objective of this study was to evaluate growth in infants with d-transposition of the great arteries (d-TGA) who underwent switch operation (anatomical correction) in the early neonatal period. Growth data (at birth and 1, 3, 6, 12, and 24 months of age) were retrieved in 23 infants with d-TGA who survived the operation without major complications. Measures were transformed into z scores and compared with normative data for age. Following surgery, infants showed low z scores for weight, height, and head circumference. Weight and height showed a trend to reach normal ranges between 6 and 12 months of age, and the z scores were positive at 24 months. z scores for head circumference were still negative at 24 months of age. No dietary interventions were implemented during this period, and the infants were fed their own mothers' milk or, before discharge, high-calorie, preterm formula. Following anatomical correction for d-TGA in the early neonatal period, infant growth shows a characteristic pattern, with parameters normalized by 12 months of age in most cases. Head growth shows a different pattern, although gross motor development seems unaffected.

Atrioventricular septal defect with 'absent' pulmonary valve in the setting of Down's syndrome: a rare association

We report a rare case of a 2-year-old boy with Down's syndrome, atrioventricular septal defect and so-called 'absent pulmonary valve syndrome'. Diagnostic imaging also revealed the presence of an anomalous high origin of the right coronary artery from the ascending aorta. Surgical repair was successful.

Extended end-to-end anastomosis with modified reverse subclavian flap angioplasty

We report a surgical treatment for neonatal aortic coarctatin associated with distal aortic arch hypoplasia. This technique offers the possibility for augmentation of the aortic arch without sacrificing the subclavian artery or using prosthetic patch material. The procedure was successfully performed in 5 patients.

Right submammary minithoracotomy for repair of congenital heart defects

OBJECTIVE

The initial experience with the right submammary minithoracotomy incision for correction of intracardiac congenital defects is reported.

METHODS

Between March 1997 and March 1999, 100 children underwent repair of congenital heart disease through this approach. Their mean age and weight were 4.6 years and 20 kg, respectively. Diagnosis included: atrial septal defect (78), ventricular septal defect (7), tetralogy of Fallot (6), partial atrioventricular canal (5), double-chambered right ventricle (3) and single ventricle with dextrocardia (1). The standard technique entailed a 5 to 6 cm right submammary incision, entering the chest through the third or fourth intercostal space (depending on the body weight), direct aortic and bicaval cannulation and aortic cross-clamping with cardioplegic protection.

RESULTS

There were no hospital deaths. Postoperative morbidity included bleeding in two cases, recurrent atrial septal defect in one, spleen injury in one. The average hospital stay was 3.5 days. All patient are currently free of symptoms and medications.

CONCLUSIONS

(1) This approach for repair of selected congenital cardiac malformations is technically feasible, safe and effective; (2) younger age is a facilitating factor; (3) hospital stays are effectively reduced.

Treatment of pulmonary artery stenosis after arterial switch operation: stent implantation vs. balloon angioplasty

The development of pulmonary artery stenosis is a potential complication during the mid- to long-term follow-up after arterial switch operation (ASO) for transposition of the great arteries. Surgical results have been disappointing and conventional balloon dilation yields a fairly important incidence of failures and recurrences. We evaluated our results with implantation of balloon-expandable stents in 5 out of 13 patients with a previously attempted unsuccessful conventional balloon dilation of pulmonary artery branch stenosis after ASO. In two more cases, stents were used as a primary procedure. Balloon angioplasty achieved a 15% increase in mean diameter of the stenosis vs. 124% with the use of stents (P< 0.01), a 10% decrease of the pressure gradient across the stenosis vs. 71% of stents (P<0.01), and a 10% drop in RV/aorta pressure ratio vs. 43% of stents (P<0.01). Compared to conventional balloon angioplasty in our series, stents were more effective in the treatment of patients with peripheral pulmonary artery stenosis after ASO. Balloon dilation should be considered in selected cases unsuitable for treatment with endovascular stents.

[Unreliability of pulse oximetry in hypothermic children after cardiovascular surgery with deep hypothermic circulation]

BACKGROUND

The aim of the study was to evaluate the accuracy of oxygen saturation with the pulse oximeter (SpO2) in children undergoing cardiovascular surgery with deep hypothermic circulation.

METHODS

The SpO2 values measured at the hand and at the foot were compared in 50 patients with the arterial oxygen saturation (SaO2) measured with the oximeter. A variance value between the two measurements less than 3% was considered as a reliable measurement, and the precision of the measurement was defined as the standard deviation of the variability.

RESULTS

For skin temperature between 35 and 28 C grade, and for core temperature more than 34 grade, the SpO2 is a reliable measurement of the SaO2; for skin temperature less than 28 grade and core temperature less than 34 grade the SpO2 do not correspond the SaO2.

CONCLUSIONS

The variability and the precision of the measurements are not affected the position of the probe (hand or foot).

Pitfalls in echocardiographic-based repair of aortic coarctation

The knowledge of echocardiographic pitfalls, which may impair the correct indication for surgery of aortic coarctation, is of great importance to pediatric cardiologists. We believe that only the suspicion of coronary artery anomalies is a clear indication to perform a cardiac catherization.

Partial atrioventricular canal with congestive heart failure in the first year of life: surgical options

BACKGROUND

An important subgroup of patients with partial atrioventricular canal require an operation in the first year of life because of refractory congestive heart failure.

METHODS

From June 1982 to April 1995, of 128 patients with partial atrioventricular canal, 35 patients (27%) underwent surgical treatment at less than 1 year of life. Associated cardiac anomalies were present in 22 patients. Only 7 patients (20%) had Down's syndrome. Five patients with left ventricular hypoplasia underwent aortic coarctectomy (3 patients) or Norwood operation (2 patients). The other 30 patients underwent anatomic repair in 24 cases and aortic coarctectomy in 6. The surgical results of patients submitted for anatomic repair were retrospectively correlated with the echocardiographic mitral valve diameter.

RESULTS

There were 7 deaths (29%) after anatomic repair, 2 (22%) after aortic coarctectomy, and 2 (100%) after Norwood operation. Infants with a mitral valve diameter less than 2.5 x 10-2 m/m2 died at repair. In a mean follow-up of 73.5 months there were five secondary mitral valve plasties and three repairs after aortic coarctectomy.

CONCLUSIONS

Among patients with partial atrioventricular canal, there is an important subgroup with clinical signs of heart failure in the first year of life. Left-sided obstructive lesions and complex mitral valve anomalies seem to play a fundamental role in the clinical evolution and prognosis of these patients. The echocardiographic mitral valve diameter may be useful for determining the correct surgical indication.

[Diaphragm paralysis following pediatric heart surgery. Review of 25 treated cases]

Postoperative diaphragm paralysis after pediatric heart surgery is the cause of respiratory insufficiency for which there is currently no agreed treatment. The two hypotheses now considered are: early folding of the diaphragm or longterm assisted ventilation. A retrospective study from 1988 to January 1995 on the incidence of diaphragm paralysis and the type of treatment performed was carried out by the Department of Pediatric Heart Surgery of the Bambino Gesù Hospital in Rome. A total of 25 patients presented diaphragm paralysis out of 3400 operations performed and the clinical records of these patients in intensive care were reexamined. The patients were aged between 2 days and 5 years (mean 3 years) and weighed between 3 kg and 15 kg (mean 6.5). The diagnosis of diaphragm paralysis was made using fluoroscopy of the pulmonary fields during spontaneous breathing; 13 patients were extubated 7 days after diagnosis, 12 underwent surgical folding and were extubated immediately after surgery. The authors underline the particular intolerance to ventilatory insufficiency of pediatric patients after the correction of congenital cardiopathies and the need for early intervention to shorten the stay in intensive care and to avoid the onset of other severe complications such as infection. In particular, in patients undergoing Glenn's or Fontan's modified operation, the integrity of the ventilatory apparatus is essential for the correct function of the new hemodynamic status.

Neonatal pulmonary autograft implantation for cardiac tumor involving aortic valve

We diagnosed in a 4-day-old neonate a cardiac tumor involving the left atrium, left atrioventricular junction, left ventricular outflow tract, and aortic valve with severe subvalvular and valvular aortic stenosis. The critical involvement of the aortic valve and the scarcity of neonatal cardiac donors led us to perform a successful replacement of the aortic root with a pulmonary autograft, using a very small homograft for the native pulmonary valve (Ross operation).

Total cavopulmonary direct anastomosis: a logical approach in selected patients

A 2.5-year-old boy with a diagnosis of situs solitus, tricuspid atresia, anatomically corrected malposition of the great arteries (S,D,L), left juxtaposition of atrial appendages, and pulmonary stenosis underwent successful total cava-to-pulmonary connection by means of a superior vena cava-to-pulmonary artery end-to-side anastomosis associated with an inferior vena cava-to-pulmonary artery direct anastomosis. Anatomic features and surgical technique are described.

Airway obstructions associated with congenital heart disease in infancy

Significant airway obstruction may complicate the natural and surgical history of infants with congenital heart diseases. Airway obstruction occurred in 12 infants who had operations for congenital heart disease. In all cases tracheography demonstrated the cause of airway obstruction. Significant mortality (5/12, 41.7%) and morbidity in this group of infants were the result of airway obstruction. To reduce the complications caused by airway obstruction in infants with congenital heart disease, we recommend (1) preoperative identification of patients with potential airway obstruction, (2) preoperative tracheography in high-risk infants, (3) appropriate choice of the surgical procedure, especially when insertion of a prosthetic conduit is required, (4) early recognition of the problem during the postoperative period, (5) prompt diagnosis by postoperative tracheography, with or without angiography, and (6) therapy directed at the cause of airway obstruction.

Total anomalous pulmonary venous connection: surgical repair with a double-patch technique

A double-patch technique has been used to repair total anomalous pulmonary venous connection in 35 patients (mean age, 4.9 months; mean weight, 4.2 kg). In all patients with supracardiac or subdiaphragmatic type of total anomalous pulmonary venous connection, repair has been accomplished by enlarging the "new" left atrium. There were three early deaths (3 of 35 = 8.6%) and no late deaths in a mean follow-up of 30 months (3 to 71 months). We propose this double-patch technique as an alternative surgical option for total anomalous pulmonary venous connection.

[Surgical correction of atrioventricular canal without heart catheterization]

In our department, 35 patients with atrioventricular canal underwent elective surgery between June 1983 and May 1989. The diagnosis was based on clinical and echocardiographic assessment without cardiac catheterization. Nineteen patients (age 2-12 years; mean 6.6 years) had a partial atrioventricular canal and 16 (age 5-8 months; mean 7 months) presented a complete atrioventricular canal. The echocardiographic diagnosis was confirmed at surgery in all but one patient (2.8%). The latter was diagnosed as having a complete canal but at surgery a transitional canal with a restrictive ventricular septal defect was found. We based our patient selection on the natural history which excluded cases with early heart failure and pulmonary hypertension. We also relied on an accurate morphological study using two-dimensional echocardiography which excluded cases with associated cardiac malformations. Our recent experience (1986-1989) showed that 50% of the patients with complete canal and 60% of patients with partial canal underwent surgery without cardiac catheterization.

Tricuspid valve avulsion or excision for right ventricular decompression in pulmonary atresia with intact ventricular septum

Retrograde right ventricular decompression through the tricuspid valve, by damaging or excising the valve, was attempted in five patients with pulmonary atresia, intact ventricular septum, and severely hypoplastic right ventricle. Two patients were neonates in critical condition, one of whom had received previous palliation with a shunt; the other neonate had received pulmonary valvotomy plus shunt followed by repeat valvotomy plus shunt ligation. Three patients were infants or children who had undergone placement of isolated neonatal shunts. One procedure was performed during cardiac catheterization. Three patients survived. In one, tricuspid avulsion and a Rashkind septostomy were done by percutaneous methods; in two patients, tricuspid excision plus bidirectional cavopulmonary anastomosis was done by open operation. At restudy, all showed subsystemic pressure in the right ventricle and diminution or disappearance of sinusoids. One also showed improvement of left ventricular function. Incorporation of a small right ventricle in the right atrium at the time of the two orthoterminal palliations seemed, at least, innocuous. Right ventricular decompression by tricuspid avulsion or excision could be suggested for all patients with pulmonary atresia, intact ventricular septum, hypersystemic hypoplastic right ventricle, and major sinusoids without right ventricular dependent coronary circulation in whom the outlet portion of the right ventricle is not functional.

[Seroma: a complication of systemic-pulmonary shunt with a tubular prosthesis]

The accumulation of clear fluid leaking from a tubular prosthesis and confined within a fibrous pseudomembrane has been defined as a "seroma". Both the literature and our experience on this complication have been reviewed. Fifty-three cases of seroma have been reported after implantation of a tubular prosthesis. In our experience, from June 1982 to September 1988 we observed 11 cases (11/108 = 10.1%) of seroma complicating a modified Blalock-Taussig procedure. The mean age of these patients was 2 years 2 months. The diameter of the implanted tubular prostheses was always 5 mm. Among these cases, we report the details of a child, 1 year 10 months old, in whom the seroma significantly complicated the surgical history. According to the data derived from the literature and from our experience, we derived the following risk factors for the occurrence of seroma: age of the patient, size of the prosthesis, surgical manipulations, arterial-venous gradient, transprosthetic flow.

Long-term results after extracardiac valved conduits implanted for complex congenital heart disease

Between August 1982 and December 1986, 56 patients survived implantation of an extracardiac valved conduit for complex congenital heart disease. The mean age at operation was 4.2 years (16 days to 24 yrs) and the mean weight was 15.9 kg (2.4 to 93.0 kg). The diagnosis was pulmonary atresia (PA) with ventricular septal defect (VSD) in 13 patients, tetralogy of Fallot in 11, transposition of the great arteries (TGA) with VSD in 8, truncus arteriosus, in 7, complex left ventricular outflow tract obstruction (LVOTO) in 6, complex left atrioventricular valve obstruction in 4, double outlet right ventricle with VSD and subaortic obstruction in 3, univentricular heart with pulmonary stenosis in 2, TGA with LVOTO in 1, and PA with intact ventricular septum in 1. In 35 patients, a preclotted conventional Dacron conduit (CDC) with bioprosthetic valve was used, in 19 patients a collagen-sealed Tascon valved conduit (TC) was implanted, and in 1 patient an aortic homograft was used. In a mean follow-up of 32.5 months (9 to 64 mo), there were two deaths (2/56, 3.6%) that were not related to the conduit. All survivors have been evaluated by two-dimensional and Doppler echocardiography, and 29/56 (51.8%) underwent cardiac catheterization. Nine patients (9/56, 16.1%) underwent successful valved conduit replacement, in seven cases with a nonvalved conduit. There was a significant difference (P = .011) with regard to the incidence of conduit replacement between the group with CDC (2/36, 5.5%) and the group with TC (7/19, 36.8%). Five patients underwent percutaneous transluminal balloon dilatation of the prosthetic conduit, with adequate relief of the gradient in four patients.(ABSTRACT TRUNCATED AT 250 WORDS)