Children´s Heart Center Linz

Cardiac Surgery 1997 – 2006
Operation	Number	Mortality	%
No-pump surgeries	294	5	1,7
VSD	213	1	0,5
ASD	179	1	0,6
AV - Channel	103	0	0
Tetralogy of Fallot	163	3	1,8
Transposition of the Great Arteries	125	2	1,6
Bidirectional Glenn Shunt	151	6	4,0
Norwood	135	26	19,2
Others	495	28	5,7
Total	1870	72	3,8

Cardiac Catheterization 2002
Total	128
Interventions*	363	49%
* Dilatation of valvular and peripheral pulmonary stenosis, ASD-/ PFO device closure, Stentimplantations, Coil - Occlusion of PDA, Rashkind - Procedures

Cardiac Catheterization 2001
Total	107
Interventions*	36	34%
* Dilatation of valvular and peripheral pulmonary stenosis, Stentimplantations, Coil - Occlusion of PDA, Rashkind - Procedures

Cardiac Catheterization 2000
Total	69
Interventions*	17	25%
* Dilatation of valvular and peripheral pulmonary stenosis, Stentimplantations, Coil - Occlusion of PDA, Rashkind - Procedures

Cardiac Catheterization 1999
Total	71
Interventions*	31	44%
* Dilatation of valvular and peripheral pulmonary stenosis, Stentimplantations, Coil - Occlusion of PDA, Rashkind - Procedures

Early and mid-term results of the arterial switch operation (ASO) in 114 consecutive patients: a single center experience

Background: The ASO has become the treatment of choice in patients with simple or complex transposition of the great arteries (TGA). The purpose of this study was to assess early and mid-term outcome in a single center after ASO in this patient collective.

Patients and methods: Between 1995 and December 2005 114 consecutive patients underwent an ASO at our institution, performed by one single surgeon. Patient charts, echo- and angiograms were retrospectively reviewed and patients were analyzed in 3 different groups: Group I consisted of 77 neonates with TGA and intact ventricular septum, group II of 13 patients with TGA and ventricular septal defect which had to be closed surgically and group III of 24 neonates with varies forms of TGA in a complex setting (table2). The median weight was 3.23 kg (range: 1.65 – 8.30) . Twenty five neonates were born preterm, 18 diagnosed prenatally.

Results: Thirty-day mortality rate of 1.75% was observed after complete of follow up with 1 further late death (0.89%) . Only one early coronary event occurred, no late events have been reported. After a median follow-up of 20.7 months (range 0.3-128.6) of 111 survivors 10 required cardiovascular reoperation, all but 1 came out of group III. Freedom from reoperation at 5 years was: 87.5%. Prevalence of supravalvular pulmonary stenosis was 4.7%. In our patient series the only risk factor for increased mortality and morbidity was a body weight of less than 2500g at the time of operation. No better outcome could be demonstrated in the prenatal diagnosed patients.

Conclusion: The ASO can be performed safely and with a low mortality and morbidity even in patients with complexe TGA. Follow-up of these patients is required to detect residual problems like supravalvular pulmonary stenosis, coronary problems, arrhythmias and aortic valve dysfunction.

N-terminal-pro-B natriuretic peptide levels correlate with signs of heart failure in patients after Fontan operation

Lechner E, Gitter R, Mair R, Schreier-Lechner E, Vondrys D, Tulzer G
Introduction: Ventricular function is critical in the long-term management of patients with Fontan physiology. Early and minor deteriorations are difficult to assess.
Purpose of the study: to test the hypothesis that plasma levels of N-terminal-pro-B natriuretic peptide (NT-pro BNP) in children after Fontan operation correlate with clinical sings of heart failure (CHF).
Patients and methods: NT-pro BNP plasma levels of 59 children (age: xx years, range: years) after Fontan operation (median time of follow up: years, range years) were measured using an automated enzyme immuno assay (Roche Diagnostics). All Fontan patients had a complete clinical and echocardiographic examination by a pediatric cardiologist. Clinical signs of CHF was considered if at least two of the following criteria were fulfilled: cardiomegaly in x-ray, more than mild AV – insufficiency or decreased ventricular function at echocardiography and dyspnea, tachypnea, tachycardia, hepatomegaly or failure to thrive at clinical examination. Xx patients had hypoplastic left heart syndrome, had single ventricle, xx had tricuspid atresia, xx had double outlet right ventricle with transposed great arteries, xx pulmonary atresia with intact ventricular septum, xx double outlet right ventricle and straddling mitral valve.
Results: 14/59 patients after Fontan operation had signs of CHF. In patients with CHF the NT-pro BNP levels were significantly higher (median 248.95, range: 125.2 – 1561 pg/ml) than in patients without CHF (median 94.3, range: 19.5 - 300.5 pg/ml).
Conclusion: Plasma NT-pro BNP levels are a useful tool in detecting CHF in patients postoperative Fontan operation. In the future plasma NT-pro BNP levels may be useful in monitoring the effect of various treatments for CHF in children postoperative Fontan procedure.

Open heart surgery in neonates and premature infants weighing less than 2.5 kg

Lechner E, Hofer A, Mair R, Sames-Dolzer E, Steiner JJ, Vondrys D, Tulzer G

Background: Low birth weight infants may require early surgical treatment of congenital heart defect because of their poor clinical status. Early surgical repair has been shown to be preferable to medical management or palliative surgery with delayed definitive repair.

Methods: From November 1997 to December 2006, 46 consecutive neonates weighing less than 2500 g underwent cardiopulmonary bypass operations for complete correction of congenital heart defects (n= 34) or Norwood stage I palliation for hypoplastic left heart syndrome (n=12). A retrospective analysis was performed to evaluate early and midterm outcome. The study group included 23 males and 23 females with a median age of 10 days (2 to 110 days) and a median weight of 2260g (1280g to 2480g). 34 children (74%) were born prematurely. 7 patients were critically ill and 21 were ventilated preoperatively. Diagnoses included transposition of the great arteries (13), hypoplastic left heart syndrome (12), ventricular septal defect with interrupted or hypoplastic aortic arch (5), VSD (4), tetralogy of Fallot (3), total anomalous pulmonary venous connection (2), aorticopulmonary window (1), critical valvular aortic stenosis (1), complete AV canal (1), pulmonary atresia with intact ventricular septum (1), common arterial trunk (1), left atrial tumor (1), thrombotic formation on a ventricular-atrial shunt with ASD (1),

Results: 30-day mortality was 13% (6/46). Age, gender, prematurity, additional extracardiac malformations, bypass time and aortic cross clamp time did not influence 30-day mortality. Duration of mechanical ventilation, median time at intensive care unit and median stay until discharge were 7, 12 and 26 days, respectively. At a median follow – up time of 32 months overall mortality was 19.6% (9/46). 12/37 (32.4%) survivors needed 19 reoperations and 6/37 (16.2%) patients needed interventional heart catheterization.

Conclusion: Open heart surgery can be performed in low weight infants with reduced, but acceptable early and mid-term survival.

Successful biventricular repair following in-utero balloon dilation of critical aortic stenosis
G.Tulzer, W.Arzt, R.Mair, E.Lechner, G.Geiselseder
Children’s Heart Center Linz, Linz, Austria

Critical aortic stenosis (AS) with reversed aortic arch flow in the mid-trimester fetus usually evolves into hypoplastic left heart syndrome (HLHS)
We report two cases of successful biventricular repair following in-utero valvuloplasty. Case 1 presented at 28 weeks with a grossly dilated poorly contracting left ventricle (LV), signs of endocardial fibroelastosis, mild mitral regurgitation (MR) (2,9 m/s), critical AS (1,7 m/s), reversed flow in the aortic arch and ascites. Transabdominal percutaneous valvuloplasty resulted in antegrade flow in the aortic arch, ascites disappeared within 7 days. Until delivery at 35 weeks MR velocity increased to 4,5 m/s, aortic velocity to 3,9 m/s which was attributed to improved ventricular performance. Postnatal aortic valvuloplasty was unsuccessful in reducing the gradient, so a neonatal Ross-Konno procedure was carried out. At discharge there was normal LV size and function. Case 2 had almost aortic atresia (no measurable gradient) and a dysplastic mitral valve with moderate MR (4,8 m/s) but no ascites. Balloon dilation was performed at 33 weeks followed by antegrade aortic arch flow, trivial AR, a residual gradient of 36 mmHg and improved LV shortening. Valvuloplasty after delivery at 38 weeks again could not reduce the gradient, a Ross-Konno procedure with mitral valve repair was successful in establishing a biventricular circulation with good LV function.
Conclusions: These two cases confirm that in critical AS timely in-utero aortic valvuloplasty is able to improve left ventricular performance and fetal hemodynamics in a way that the likelihood of a postnatal biventricular repair is increased.

Presented at the 4th world congress of pediatrc cardiology and cardiac surgery, Buenos Aires 18 -22 September 2005:

Levosimendan – Drug of Choice for the Failing Immature Myocardium?
Lechner E, Moosbauer W, Pinter M, Mair R, Tulzer G
Children’s Heart Center Linz, Linz, Austria

Introduction: Levosimendan is a calcium sensitizer for the treatment of congestive heart failure (CHF). Levosimendan improved hemodynamics in adults with CHF. Data on the use of Levosimendan in premature infants with CHF following cardiac surgery is limited.
Case report: A 32 weeks gestational age, 1525 g premature male twin with transposition of the great arteries underwent arterial switch operation. Immediatly postoperatively he developed signs of low cardiac output. Mixed venous saturation was 56%, serum lactate increased to 14,8 mmol/l, systolic arterial pressure (SAP) was 40 mm Hg, left atrial pressure (LAP) was 24 mm Hg and echocardiography showed reduced left ventricular function with a fractional shortening of 10%. There were no signs of reduced coronary perfusion. Milrinone, dobutamine and epinephrine did not improve hemodynamics. Levosimendan was initiated at a dose of 0,05 yg/kg/min and increased to 0,1 yg/kg/min and 24 hours continously infused. Within 6 hours after starting the levosimendan infusion LAP decreased to 7 mm Hg, SAP increased to 60 mm Hg and within 24 hours after initiation serum lactate level decreased to 1,7 mmol/l and mixed venous saturation increased to 81%, echocardiography revealed improvement of left ventricular function with a fractional shortening of 25%. There were no side effects recognized during administration of levosimendan.
Conclusion: In premature neonates with postoperative low cardiac output syndrome due to failing myocardial function levosimendan seems to be a potent inotropic agent. Since hemondynamic effects and safety of levosimendan in neonates have not been investigated yet, its cautious use is recommended.

Closed or restrictive foramen ovale in hypoplastic left heart syndrome: a significant risk factor?
G Tulzer, R Mair, E Lechner, E Sames, W Arzt
Children’s Heart Center Linz, Linz, Austria

Although surgical results in children with hypoplastic left heart syndrome (HLHS) have substantially improved, there is still a significant mortality and morbidity. A restrictive or absent foramen ovale (FO) has been shown to cause significant impairment of pulmonary vessels. The purpose of this study was to compare outcome in patients with HLHS with restrictive or closed FO ovale to those with unrestrictive FO to test the hypothesis, that a restrictive FO is a significant risk factor.
Patients and Methods: Between 1997 and 2004 60 consecutive newborns with HLHS and intention to treat were admitted to our institution. In 14 patients (23%) a restrictive FO (<3mm with a mean gradient of 10 mm Hg or more by Doppler) was found (Group A). FO was completely closed in 3 of them. Group B consisted of 46 newborns with typical HLHS and non-restricitive FO. Both groups were comparable in terms of gestational age at birth, birthweight, sex, type of Norwood operation (RV/PA conduit, modified BT shunt) and length of follow-up.
Results: are shown in Table I. Despite prenatal diagnosis and postnatal emergency treatment all 3 patients with closed FO died immediatly after birth prior to surgery due to severe hypoxemia and pulmonary lymphangiectasia. There was no significant difference in survival between both groups, however patients of group A required significantly more and longer intensive care therapy after the Norwood operation and also after the modified Glenn procedure. Five patients with restrictive FO had procedures performed prior to stage I Norwood (surgical atrioseptectomy: 1, ballon atrioseptostomy: 4) to relieve pulmonary venous congestion. Patients of group A also had significantly more days of ventilation and days of NO therapy.
Conclusions: A closed FO in patients with HLHS was associated with preoperative death despite emergency treatment. Patients with restrictive FO had more postoperative (respiratory) problems, which could be handled with more and longer intensive care therapy. Despite there was no difference in short time survival, further studies must be performed to assess long term outcome.
Speculations: fetuses with HLHS and closed FO could be considered as possible candidates for in-utero atrioseptostomy to relieve pulmonary venous congestion and to prevent pulmonary lymphangiectasia.

Progression of fetal congenital heart disease and rationale of prenatal intervention
G.Tulzer

In postnatal life progression of heart disease has been clearly documented. Natural history studies have been performed and as a consequence, guidelines for interventions (drugs, interventional or surgical procedures) have been developed. Early detection of fetal heart disease, even in the first trimester, is feasible and these fetuses can be followed in-utero for months. Progression of fetal congenital heart disease has been widely documented in case reports and small case series. Any cardiac valve can become more stenotic, even atretic or more incompetent during the course of pregancy, potentially leading to secondary damage to the heart and lungs. Consecutive impaired growth of ventricles and/or vessels may result in a univentricular circulation postnatally. Valve regurgitations have the potential to lead to hypertrophy, congestive heart failure and hydrops. Theoretically, as in postnatal life, timely fetal intracardiac intervention should lead to normalization or improvement of flows, pressures and hemodynamics, thus preventing secondary damage to the fetal heart and organs, congestive heart failure or fetal death. Cardiac lesions, that might profit from timely interventions could be subgroups of: critical valvar aortic stenosis, critical valvar pulmonary stenosis, pulmonary atresia with intact septum or a closed or severly restricitve foramen ovale in cases of left heart obstructive lesions like e.g. hypoplastic left heart syndrome. Successful in-utero dilatation of aortic and pulmonary valve, perforation of valvar pulmonary atresia and atrio-septostomy with ballon dilation of the created ASD have already been reported. As these procedures carry a high risk of technical problems, morbidity and mortality, careful patient selection is crucial

Normal mid-trimester heart: echo features
G Tulzer

A very good time for a routine fetal echocardiography is between 18 and 22 weeks gestation. Cardiac structures are usually best visualised at that time.
As in postnatal echocardiography a segmental approach to the fetal heart should be used.
1) Fetal position, Situs
2) Four chamber view:
a. Atria (venous connections)
b. Atrioventricular connections
c. Ventricles, Septum
3) Ventriculo-arterial connections
4) Great vessels, arches

The first thing to start with is to determine fetal position (breech or vertex) in order to be able to establish the situs of the baby’s organs and right-left relationships. IVC and SVC should connect to the right and pulmonary veins to the left atrium.
Four-chamber view: it is obtained in a cross section of the fetal chest above the diaphragm. The area of the fetal heart should not exceed 1/3 of the chest area. It is important to judge the symmetry of all 4 chambers. Both ventricles should be of almost equal size as should be the atria. There should be 2 clearly separated AV valves connected to good performing (squeezing) ventricles. Larger defects of the ventricular inlet septum can be ruled out in this view.
Outflow tracts: Moving the scan plane from the 4-chamber view towards the fetal head allows visualisation of both outflow tracts. First the left ventricular outflowtract with aortic valve can be seen followed by the crossover of the right ventricular outflowtract with pulmonary valve and pulmonary artery bifurcation. Both great vessels should be of approximately the same size, too, and any disproportion at the great artery level is suspicious of a cardiac anomaly. Further continuation of this sweep towards the fetal head reveals the
Fetal aortic and ductal arch: these two arches run in a „V“-shaped fashion towards the fetal spine, joining to form the descending aorta. Together with the superior vena cava, 3 vessels can be seen in a high cross sectional plane of the fetal chest (3-vessel view, see image below) Like the atria, ventricles and great vessels, these arches should be of almost equal size. Both can also be visualised in a modified saggital plane. The aortic arch is identified by the originating head vessels, the more posterior origin (in the middle of the heart) and the tighter curve compared to the ductal arch.

Doppler has significantly increased the amount of information that can be obtained from an echocardiogram. Doppler ultrasound allows quantification of certain cardiac lesions as well as estimation of intracardiac pressures. It also improves the assessment of ventricular performance and in combination with two-dimensional echocardiography gives information about volume flow.

Doppler echocardiography in normal fetal hemodynamics

A complete fetal Doppler echocardiographic study should include Doppler interrogation of blood flow across the AV valves (tricuspid- and mitral valve), semilunar valves (pulmonary valve, aortic valve), ductus arteriosus and inferior vena cava (IVC) and/or hepatic veins (HV). Additionally it is possible to sample flow of pulmonary veins (PV) near the left atrium and flow across the foramen ovale.

AV-valve Doppler
Doppler examination of flow across the AV valves provides information about the presence of AV valve regurgitation and/or stenosis. Additionally, diastolic function and cardiac rhythm can be assessed. In the normal human fetus there is no difference in the shape of the Doppler tracing across tricuspid or mitral valve. As in postnatal life it consists of two clearly separated peaks, the first peak representing early diastolic ventricular filling (E-wave) and the second peak representing late diastolic ventricular filling due to atrial contraction (A-wave)
Attention should be paid to the following points:
(1) Two separate peaks in the Doppler tracing? This suggests normal cardiac rhythm and AV conduction. However when the heart rate increases above 180 beats per minute, both peaks move closer together and may appear as only one peak.
(2) Inflow velocity within normal range for gestational age? It is increased in the presence of AV valves stenosis or volume overload of the respective ventricle or both, and decreased in congestive heart failure.
(3) AV valve regurgitation? Colour Doppler is superior to PW or CW Doppler in detecting regurgitant jets within the atria. In a normal fetus with a structurally normal heart, AV valve regurgitation is a rare finding and, if present, only trivial. Thus, AV valve regurgitation is a strong marker of a structural or hemodynamic abnormality and must lead to a careful fetal evaluation.

Semilunar valve Doppler
Doppler examination of flow across the semilunar valves provides information about the presence and severity of valvar stenosis and/or regurgitation. Additionally, it can be used to assess systolic function and cardiac output.
Attention should be paid to the following points:
(1) Velocity within normal range for gestational age? Increased velocities suggest either valvular stenosis or increased flow. Decreased velocities may be a sign of heart failure
(2) Valvular regurgitation? Diastolic backward flow into the left or right ventricle is abnormal and suggests structural and/or hemodynamic pathology.

Ductus arteriosus
In the normal human fetus the highest blood velocity is found within the ductus arteriosus. More than 50% of the combined ventricular output is crossing this vessel. Flow across the ductus arteriosus can be affected in many ways. Therefore interrogation of ductus arteriosus blood flow velocity should be part of a complete fetal echocardiogram.
Attention should be paid to the following points:
(1) Peak velocity within normal range for gestational age? Increased peak velocity occurs during ductal constriction and increased right ventricular output (drug effect?, anaemia?, hypervolemia?, structural heart defect)
(2) PI < 1.9: ductal constriction; PI > 3: increased RV output
(3) Peak velocity below normal range: congestive heart failure
(4) Direction of flow: reversed flow means ductal dependent pulmonary circulation after birth!

Disproportion in the second trimester: the likely diagnosis
G.Tulzer

In the normal fetal heart, there is usually symmetry of all cardiac chambers and great vessels. Any sign of disproportion is suspicious and should prompt a detailed fetal echocardiogram. Disproportion can involve the atria, ventricles or the great vessels or all of them.
Isolated disproportion of the atria: the most likely situation would be to find an isolated enlarged right atrium. The reasons for this relate to the many causes for heart failure, but the right atrium is a final pathway for blood flow returning to the heart and will manifest enlargement in situations of relative foramen obstruction, volume overload, tricuspid valve regurgitation, and increased afterload. Increased RA size may be due to increased RV end-diastolic pressure, which may be due to, increased afterload or myocardial impairment.
Isolated disproportion of the ventricles: it is mandatory to find out whether disproportion is caused by enlargement or hypoplasia of one ventricle. Both hypoplastic left and hypoplastic right heart syndrome (like tricuspid atresia or pulmonary atresia with intact septum) may have normal size atria. Whereas in HLHS there is additional hypoplasia of the aorta, in HRHS there can be a normal size pulmonary artery.
Disproportion at the atrial and ventricular level: this is the usual situation. Enlargement or hypoplasia of a ventricular chamber is usually accompanied with enlargement of the respective atrium. Enlargement of the right ventricular cavities may be due to congenital heart disease (coarctation, VSD, TAPVR), acquired (constriction of the ductus arteriosus) or the consequence of a hemodynamic abnormality (anaemia, volume overload, increased afterload in IUGR...)
Disproportion at the level of the great arteries: although in most cases associated with disproportion in the 4-chamber view, this situation may occur also in the presence of a normal symmetrical 4-chamber view as well. Causes can be subarterial VSDs with anterior or posterior malalignment causing subpulmonary or subaortic obstruction respectively or valvar abnormalities (e.g.poststenotic dilatation)
Disproportion can occur in a normal fetal heart, too. It is usually observed in the third trimester and towards term. The right sided chambers are larger than the left sided chambers but with an overall normal heart size (area ratio heart/thorax less than 0,35). In this situation any other causes of disproportion (coarctation, TAPVR or IUGR) have to be carefully excluded before assuming the finding within normal limits.

Interventional experience in Linz:

1) PA/IVS: you know all about this case and have the Lancet ref. + USOG 2003,21:186-188
2) 26.week: Crit AS, severe MR: successful dilatation, severe bleeding and anaemia, died during first night after the procedure
3) 21.week: Crit AS, dilated LV: LV thrombus formation short after LV puncture, died during procedure

Examples for „what’s wrong with this scan“
1) Ebstein
2) Taussig Bing (DORV, S,D,D Subpulmonary VSD, hypoplastic arch)

Re-Coarctation after Norwood-Operation in Children with Hypoplastic-Left-Heart-Syndrome

Gitter R., Lechner E., Mair R., Tulzer G.

Background: Re-Coarctation (Re-Coa) is a critical condition in children after Norwood-Operation. We review our experience with Re-Coa in infants with Hypoplastic-left-heart-syndrome (HLHS).
Methods: Between 1997 and 2003 60 consecutive newborns with HLHS underwent Norwood-procedure in our institution. Reconstruction of the aortic-arch was carried out with homograft material from the ascending aorta to the isthmus. Resection of the isthmus was not performed. Analyzed parameters were prevalence, time interval between surgery and diagnosis, treatment and outcome. Re-Coa was defined by blood-pressure-difference more than 20mmHg between right arm and legs or by clinical and echocardiographic findings.
Results: 9/60 patients (15 %) developed Re-Coa. Time-interval from Norwood-Operation was 2-8 months (median 4,5). 2 children were before and 7 after Glenn-Operation. 3/9 (33%) had signs of congestive-heart-failure (CHF). RR-difference ranged from 15-55mmHg. All had moderate to severe tricuspid-insufficiency.
Body-weight at cardiac-catheterization was 3,2-6,4kg (median 4,8). Peak-to-peak gradient was 10-55mmHg (median 30) and was lower in the CHF group. In all patients the site of obstruction was the most distal part of the aortic-arch. Descending aorta was 6-9mm and defined the maximum balloon-diameter. Angioplasty was performed retrograde in 7 and antegrade in 2 patients. In all cases a 20mm Tyshak®-Ballon over a 0,014inch floppy-guide-wire was used. Residual gradients ranged from 0-18mmHg (median 7,5). Complications were transient femoral-artery-occlusion in one case; three patients required repeat angioplasty within 3-6months and a stent was implanted in one case. Six patients are free from Re-Coa in follow-up of 14-80 months (median 34). CHF disappeared in all patients except one child with spongy-myocardium. There were two late-deaths. One patient with spongy-myocardium died 9 months and one patient with severe pulmonary AV-malformations died 12 months after angioplasty, both without aortic reobstructions.
Conclusion: Re-Coa of the reconstructed aortic arch after Norwood-Operation was a frequent complication (15%). It developed early after surgery and frequently with severe signs of CHF. Angioplasty of Re-Coa was safe and effective even in the CHF-group. However re-obstruction can occur and might be due to residual ductal-tissue in the aortic-arch. Complete resection of ductal-tissue and the isthmus in Norwood-Operation may be beneficial.

The Fontan Procedure in Patients with Severe Pulmonary Arterio-Venous Malformations after a Bidirectional Glenn Operation
Mair. R., Sames E., Hofer. A., Lechner E., Gitter R., Steiner J., Pinter M., Tulzer G.

Objective
Pulmonary arteriovenous malformations are frequently seen after the bidirectional Glenn op-eration in single ventricle patients. Regression of PAVMs after the Fontan procedure is de-scribed at least in some case reports.
PAVMs can lead to serious cyanosis in patients with a bidirectional Glenn and to severe in-tractable hypoxemia in the immediate postoperative period after the Fontan procedure. After getting off CPB, when pulmonary vascular resistance is usually raised, PAVMs lead to un-controlled and unquantifiable intrapulmonary shunting.
The purpose of our study is to document the effectiveness of nitric oxide in severe hypoxemia after Fontan operations caused by PAVMs and the tendency of regression of these malforma-tions after the Fontan procedure.
Methods
Since July 2001 6 patients with severe pulmonary AV- malformations after bidirectional Glenn underwent an extracardiac Fontan procedure in our unit.
All patients had received a bidirectional Glenn 2 – 6 months (0,15 - 0,52 yrs.) after initial pal-liation. O2 saturations prior to the Fontan procedure ranged between 50 and 87%.
Because of intolerable hypoxemia 5 patients received inhaled NO soon after weaning from cardiopulmonary bypass. Inhalation was continued in the intensive care unit as long as neces-sary.
All patients were followed by contrast echocardiography, pulsoxymetry and 3 of 6 by cathe-terisation to identify the changes in intrapulmonary shunting after the Fontan operation.
Results
In 5 cases out of 6 inhaled nitric oxide was used to treat intolerable hypoxemia under 60 % of oxygen saturation. In all cases oxygen saturation could be raised above 75 %. Duration of NO application was 6 -15 days ( 10,5 ± 4,2 days).
In the follow up the disappearance of PAVMs is documented in 3 patients by cardiac cathe-terisation. All patients now have oxygen saturations above 90 % under room air ventilation.
Conclusions
Nitric oxide seems to be a potent agent for redistribution of pulmonary blood flow into the alveolar capillary bed in cases of severe PAVMs at the Fontan operation. Because of the pre-sumable regression of PAVMs in the first year after the Fontan operation we recommend the early unfenestrated completion of cavopulmonary shunt in these patients.

Right ventricular to pulmonary artery shunt instead of modified Blalock Taussig shunt improves diastolic systemic and cerebral flow in newborns after the Norwood procedure

G.Tulzer, R Mair, R.Gitter, E Lechner, E Sames, G Geiselseder

Children’s Heart Center Linz, Department of Pediatric Cardiology

In newborns, who underwent a Norwood procedure due to a functionally univentricular heart combined with aortic arch hypoplasia, pulmonary blood flow is usually established via a modified Blalock Taussig shunt (BTS). The lower pulmonary vascular resistance causes a diastolic run-off into the pulmonary vascular bed, leading to low diastolic systemic pressures and thus decreased coronary perfusion pressure. Especially with large shunts, the single ventricle faces a decreasing coronary perfusion with increasing workload. This has been attributed to contribute to the early and late mortality and morbidity after stage I palliation. Placement of a right ventricular to pulmonary shunt (RV/PA) avoids this diastolic run-off and should therefore improve systemic diastolic flow. To assess differences in hemodynamics echocardiographic data of 16 newborns, who underwent a Norwood procedures was analyzed. 8 newborns with a BTS were compared to 8 newborns with RV/PA Shunt (5 mm diameter). Between the groups there was no significant difference in weight, preoperative complications or bypass time. There was no significant AV valve or pulmonary valve regurgitation except in 1 case with RV/PA Shunt. Echocardiography was carried out, when children were extubated and in a hemodynamically stable condition. There were no significant differences in ventricular inflow and outflow velocities or in shortening fraction. Doppler examination of descending aortic flow showed holodiastolic reversal of flow in all children with BTS but holodiastolic antegrade flow in 7/8 children with RV/PA Shunt. Doppler interrogation of the arteria cerebri anteror showed significantly lower pulsatility index due to higher enddiastolic and mean velocities in the group with RV/PA Shunts. Measured gradients across the RV/PA Shunt were 3,46 +/-0,7 m/s (mean +/- std dev) suggesting normal pulmonary artery pressures.
Right ventricular to pulmonary artery shunt instead of modified Blalock Taussig shunt improves diastolic systemic and cerebral flow in newborns after the Norwood procedure and should thus improve coronary and brain perfusion leading to a more stable hemodynamic situation after stage I palliation.

Intraoperative interventional closure of a large apical VSD using the Amplatzer-VSD-occluder in a child with complex cyanotic heart disease

R.Gitter, R.Mair, E.Sames, M.Pusch, E.Lechner, Childrens Heart Center Linz, Austria

Background: Surgical closure of apical muscular ventricular septal defects (mVSD) is difficult, prolonges duration of cardiac arrest in the surgical correction of complex cardiac lesion and often requires left ventriculotomy. We report a case of intraoperative closure of a large apical VSD using the Amplatzer VSD-occluder in order to shorten and simplify surgical procedure.
Patient: A 2,5 year old boy with the diagnosis of double-outlet-right-ventricle (S,D,D) with large, doubly committed VSD, severe infundibular and valvular pulmonary stenosis and additional apical muscular defects underwent intracardiac repair. The left ventricle was baffeled to the aorta, a homograft placed from right ventricle to pulmonary artery and the largest muscular VSD was considered for intraoperative device closure.
After right ventriculotomy the large subarterial VSD allowed good visibility of the apical region from both chambers and easy localisation and passage of the defect with a 4,5mm probe. After introducing a guide wire from right ventricle across the VSD into the left ventricle a short 7-F delivery-sheeth was advanced until it appeared in the left chamber. The distal retention disc of an Amplatzer-mVSD-occluder with a waist of 6mm was opened in the cavity of the left ventricle and aligned to the septal surface by applying traction on the steering cable. By withdrawing the sheeth the proximal retention disc opened on the right side straddling the interventricular septum. Mechanical hold was proven by pushing and pulling the cable before the device was released by unscrewing it. The whole intervention was carried out in less than ten minutes and without any complication. Subsequently surgical procedure was completed.
Postoperative echocardiography showed ideal position of the device but also an additional large apical mVSD not covered by the device.
Discussion: The interventional closure of the large apical VSD was simple, time-sparing considering duration of cardio-pulmonary bypass and avoided left ventriculotomy. Preoperative accurate localization of all defects is crucial for successful device implantation. Devices with a larger distal retention disc, covering a larger surface of the ventricular septum may help in cases of multiple apical defects

Interventional closure of a large isolated coronary artery fistula in an infant using an embolization coil

R.Gitter, E.Lechner, A.Hofer, G.Tulzer; Childrens Heart Center Linz, Austria

Background: Coronary artery fistula (CAF) is a rare congenital anomaly that may become symptomatic in infancy due to severe intracardiac left-to-right shunt. Early surgical management is a well-established treatment resulting in near 100% success rate.
We report a case of transcatheter coil-embolization of a large CAF from the right coronary artery to the right ventricle in a 5 month old girl.
At the age of 4 weeks a large coronary artery fistula was found by echocardiography in the asymptomatic child with a systolic-diastolic murmur. Repeated echocardiograms revealed progressive enlargement of the fistula, increasing enddiastolic left ventricular diameter with moderate mitral valve insufficiency, and complete retrograde flow during diastole in the abdominal aorta. Left-to-right-shunt increased to 2:1 and the child was considered for transcatheter closure of the fistula.
Selective angiograms showed a large and extended fistula from the right coronary artery leading around the tricuspid valve annulus in a twisted course and draining to the right ventricle just below the valve-apparatus. Narrowest diameter was 6mm and most distally was an aneurysm of 10mm in diameter. The opening into the right ventricular cavity was 4mm. Only one normal side branch could be seen in the distal portion of the fistula.
After placing a torque-control guide wire through the right coronary artery across the fistula and the right ventricular outflow tract into a peripheral pulmonary artery, a 5F thin-wall guiding catheter with a 0,041inch lumen was advanced to the distal aneurysm. Then a Cook embolization-coil (5mm, 5 loops) was delivered to the end of the aneurysm and released as control angiography showed no residual shunt. There were no procedure-associated complications, fluroscopy-time was 22 minutes. Patient left hospital 2 days after intervention.
Echocardiographic follow-up 4 weeks and 3 months after intervention confirmed proper position of the coil, complete occlusion of the fistula and reduced signs of left-ventricular overload.
Discussion: Transcatheter embolization of the large coronary artery fistula was technically safe and easy, complete closure could be achieved and sternotomy could be avoided. Interventional closure of symptomatic coronary artery fistulas may be a less invasive alternative to surgical treatment even in young infancy.

Successful percutaneous valvotomy in a fetus with pulmonary atresia intact septum.
Tulzer, G., Arzt, W., Linz

Pulmonary atresia with intact ventricular septum (PAIVS) associated with RV hypoplasia was diagnosed in a 27 week fetus. Doppler examination revealed holosystolic tricuspid regurgitation (TR), suprasystemic RV pressure and signs of heart failure by umbilical venous pulsations. Due to the bad prognosis, in-utero interventional therapy was attempted. An ultrasound guided puncture of the hypoplastic RV was performed using a 16 gauge needle. The needle tip was directed into the RVOT and then through the atretic valve into the main PA. A 2.8 F standard coronary balloon catheter (4mm / 1,5 cm) was then inserted over a guide wire, placed across the pulmonary annulus and inflated. Immediately after the procedure turbulent (1.5 m/s) antegrade flow across the PV and holodiasstolic regurgitation could be documented, the velocity of the TR jet had decreased to 1,8 m/s, RV filling had improved from monophasic to biphasic filling and the venous Doppler was unchanged. Four weeks later the velocity across the PV had increased again to 3.4 m/s, TR had disappeared. Valvotomy of the pulmonary valve in the fetus is feasible. It leads to decompression of the right ventricle, improved filling. If it is sufficient to initiate RV growth still has to be determined.

EVALUATION OF MYOCARDIAL PERFORMANCE IN FETUSES WITH UNIVENTRICULAR HEARTS USING THE DOPPLER TEI-INDEX

Abstr_Authors: E. Lechner, G. Tulzer, R. Gitter, R. Mair

Abstr_Institution: Children’s Heart Center Linz, Department of Pediatric Cardiology

Abstr_Body:
In fetuses with univentricular hearts the remaining cardiac chamber has to take over the work of the missing ventricle. Therefore the whole cardiac output must be pumped by a single ventricular chamber leading to chronic volume overload. Nevertheless in the absence of significant atrioventricular valve regurgitation congestive heart failure rarely occurs. To assess the impact of chronic volume overload on myocardial performance in fetuses with univentricular hearts the Doppler Tei index was used. This index is independent of ventricular geometry and heart rate and can easily be obtained from a Doppler ventricular inflow and outflow trace. Tei index = (ICT+IRT)/ET, where ICT is isovolumetric contraction time; IRT: isovolumetric relaxation time and ET: ejection time. Published normal values show no difference between right and left ventricles and no change during gestation. A normal Tei index is considered to be less than 0,42.
Tei - index was measured retrospectively in 20 fetuses (Gestational age: 31 +/- 8 weeks) with univentricular hearts (Hypoplastic left heart (HLHS): n=13; tricuspid atresia (TA): n=4; double inlet left ventricle: n=2). None of the fetuses had any other extra cardiac malformation, more than trivial AV valve regurgitation, the venous Doppler measurements were normal and there were no detectable signs of heart failure in utero. All had birth weights within normal limits and underwent surgery within the first week of life. Tei index was 0,55 +/- 0,17 (mean +/- std. dev). Only 20% (4/20) had a normal Tei index of less than 0,42 ( 3 fetuses with HLHS, 1 with TA), 2/20 had an index of more than 0,80 (2 fetuses with HLHS). Although there was a tendency towards higher Tei indices in fetuses with single right ventricles versus single left ventricles, the difference was not significant.
Fetuses with univentricular hearts may have abnormal myocardial performance. The Tei index might be a sensitive and useful indicator to detect fetuses at risk for congestive heart failure.

HYPOPLASTIC LEFT HEART SYNDROME – CONTEMPORARY RESULTS
Lechner* E, Tulzer G, Mair* R, Geiselseder* G, Meindl* R, Anzengruber* A
From the Departments of Pediatric Cardiology, Children´s Hospital Linz, Austria
Cardio-thoracic Surgery and Anaesthesia, General Hospital of Linz, Austria

Typical hypoplastic left heart syndrome (HLHS) is the most common defect with one functional ventricle. Left untreated HLHS is usually fatal within the first month of life. Management of HLHS remains controversial. Either the staged Norwood procedure or heart transplantation are favored by some centers. At our institution the staged Norwood procedure was offered to all newborn with HLHS. From October 1995 to February 2001 35 patients were diagnosed with HLHS (13 prenatally ). The aim of this study was to analyze outcome of gravidity, survival, complications, morbidity, physical and neurological development after Norwood procedure. At a median gestational age of 30 weeks HLHS was diagnosed prenatally. There were three terminations. Out of the 32 newborn diagnosed with HLHS 28 underwent Norwood stage I palliation. Operation was performed at a median age of 7,5 days, the median weight was 3,4 kg. Five babies also had extra cardiac malformations. In the years 1995 and 1996 all of the 4 operated patients died. Since 1997 stage I hospital survival was 69% ( 19/28). Early postoperative complications were: thromboembolic events (n=3), seizures (n=4), rupture of the aorta (n=1) and arrhythmias (n=2). Four patients were lost late ( one fulminant sepsis ,one aortic arch – restenosis, one nonrotation of the bowel and one cardiac failure. 15 patients underwent stage II at a median age of 4 months . The physical development of 10 survivors is within the normal range, 3 are delayed . Neurodevelopment of the 13 who have already undergone stage II (follow – up 1 to 37, median 13 months) is normal in 8, four patients show a moderate delay and one has discrete hemiparesis.
Conclusion: HLHS is often but mostly late diagnosed prenatally. These data demonstrate like previous studies that mortality of stage I palliation is significant and the postoperative management is very complex. After successful stage I and II palliation normal growth in all and normal neurodevelopment in the majority of patients during short time follow – up is possible.

Real-time 3D versus 2D echocardiography in fetuses with normal and abnormal hearts

G Tulzer, W Arzt*

Children’s Heart Center Linz, Department of Pediatric Cardiology
* Maternity Hospital of Linz, Department of Prenatal Medicine

Real-time 3D echocardiography is thought to be a better method to investigate a complex three-dimensional structure like the human heart. To test clinical feasibility and usefulness of real-time 3D echo in human fetuses we compared this method to conventional 2D echo in 20 consecutive, unselected fetuses with normal and 10 fetuses with abnormal hearts. Diagnoses encompassed at least one of the following: transposition of the great arteries: (n=4); hypoplastic left heart syndrome (n=3); double outlet right ventricle (n=2); tricuspid atresia (n=1); critical aortic stenosis: (n=2), tetralogy of Fallot (n=1). After acquisition of a real-time 3D data-set (duration 1 to 5 seconds; 16 frames/second; 4 to 45 megabyte) it was stored on a remote computer for later off-line analysis. Acquisition-time was between 0,5 to 2 minutes. Off line analysis (done by a different person, not aware of the 2D examination result) included identification of: venous connections, 4-chamber view, atrio-ventricular and ventricular arterial connections, aortic and ductal arches. In normal fetuses off line analysis lasted on average 3 to 4 minutes, in fetuses with congenital heart disease 15 to 40 minutes. Assessment of the 4-chamber view and outflow tracts was excellent and comparable to the 2D echo in 20/20 normal fetuses, arches in 12/20, venous connections in 10/20. In fetuses with abnormal hearts, the main pathology was clearly detectable in all. Compared to 2D echo assessment of chamber size, AV valves, papillary muscles and VSD relationship was superior or equal, great vessel anatomy could not be assessed in 1 and was otherwise inferior or equal. New views provided additional information in 2/10 fetuses. Real-time 3D echo was reliable for 4 chamber view and outflowtract screening. Advantages over 2D examination are that it may significantly shorten examination time, improves patient comfort, provides excellent data storage and enables electronic data transfer to remote experts, who can examine the fetal heart in real-time. In abnormal hearts it may add additional information due to new views and 3D reconstructions, which can be rotated in space. Limitations were slow frame rate, low lateral resolution and lack of (color) Doppler.

Short term follow-up after the Ross operation in children
Mair, R., Tulzer, G., Rosenbichler A., Geiselseder.G.

Aortic root dilatation, early homograft stenosis and left ventricular dysfunction due to coronary problems are major concerns of the pulmonary autograft replacement of the aortic root in children. The purpose of this study was to assess the short-term follow-up in children after the Ross procedure. The charts of 13 consecutive children, with severe aortic regurgitation who underwent the Ross procedure in our institution were retrospectively reviewed. Median age at operation was 10±5.4 years, median weight 31.8±17 kg. All patients survived (median hospital stay:14±5.8 days). The neo-aortic valve showed no or trivial insufficiency in all but 1 child (grade II). Median follow-up was 25±18 months. Analysed parameters were LVEDD, diameters of the aortic valve annulus and aortic sinuses and paired t-test was used for statistics. LVEDD decreased significantly after surgery (p<0,0001), LV shortening fraction (SF) decreased from 32±5 to 23±7 (p<0,003) but improved to normal within 6 months in all but 1 patient who had a decreased FS preoperatively. Postoperatively there was no significant increase of the neo-aortic valve diameter (p<0.089) but a significant increase in diameter at the level of the sinuses at 12 months (N=7; p<0.041) and 24 months (N=6; p<0.026) without aortic valve impairment. In a 2-year-old patient the homograft in pulmonary position had to be changed due to severe stenosis 5 months after the Ross procedure. The Ross procedure in childhood appears to be a save procedure and leads to a prompt reduction in LVEDD. Reduced movement of the IVS might cause transient reduced SF. There was evidence that dilation of the neo-aortic sinuses occurs. The significance of these findings regarding coronary filling and aortic valve competence must be assessed in long term studies.

Elastin: mutational spectrum in supravalvular aortic stenosis.
Metcalfe K, Rucka AK, Smoot L, Hofstadler G, Tuzler G, McKeown P, Siu V, Rauch A, Dean J, Dennis N, Ellis I, Reardon W, Cytrynbaum C, Osborne L, Yates JR, Read AP, Donnai D, Tassabehji M.

University Department of Medical Genetics and Regional Genetics Service, St Mary's Hospital, Manchester, UK.
Supravalvular aortic stenosis (SVAS) is a congenital narrowing of the ascending aorta which can occur sporadically, as an autosomal dominant condition, or as one component of Williams syndrome. SVAS is caused by translocations, gross deletions and point mutations that disrupt the elastin gene (ELN) on 7q11.23. Functional hemizygosity for elastin is known to be the cause of SVAS in patients with gross chromosomal abnormalities involving ELN. However, the pathogenic mechanisms of point mutations are less clear. One hundred patients with diagnosed SVAS and normal karyotypes were screened for mutations in the elastin gene to further elucidate the molecular pathology of the disorder. Mutations associated with the vascular disease were detected in 35 patients, and included nonsense, frameshift, translation initiation and splice site mutations. The four missense mutations identified are the first of this type to be associated with SVAS. Here we describe the spectrum of mutations occurring in familial and sporadic SVAS and attempt to define the mutational mechanisms involved in SVAS. SVAS shows variable penetrance within families but the progressive nature of the disorder in some cases, makes identification of the molecular lesions important for future preventative treatments.

Operation	Anzahl	< 1 Jahr	Mortalität
VSD	31	26	0
ASD	24	0	0
AVcanal	15	15	0
TOF	29	13	0
Transposition	18	18	0
Glenn Shunt	31	31	1
Fontan	12	0	0
Norwood	19	19	4
Other complex defects	74	42	3
No-pump surgeries	34	25	0
* coarctation of the aorta, PDA ligation, Blalock-Taussig Shunts
Summe	287	188	8