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Introduction: Beneficial effects of treprostmil, a stable prostacyclin analogue, were demonstrated in patients with pulmonary arterial hypertension (PAH). Although regression of pulmonary vascular remodeling has been suggested as therapeutic mechanism, its mode of action remains unknown.Methods: Flow-associated PAH was created in rats by injection of monocrotaline (60 mg/kg) combined with an abdominal aortocaval shunt. Subsequently, rats were treated with subcutaneous treprostinil (50 ng/kg/min, treated; n = 8) or saline (untreated; n = 9). A control group underwent sham-surgery (n = 8). Animals were sacrificed at symptoms of cardiac failure, together with their matched controls.Results: Dyspnea and weight loss determined the moment of sacrifice in 8/9 untreated animals (89%) versus in one of eight treated animals (13%; log-rank test survival curves; P = 0.02). Mean pulmonary arterial pressure increased in the model (42 +/- 2 mm Hg in untreated vs. 18 +/- 1 in controls; P Conclusions: Treprostinil treatment improved clinical course and ameliorated symptoms of heart failure in a model of advanced PAR However, beneficial effects were not associated with reversed structural remodelling of the pulmonary vasculature.

Chronic increased pulmonary blood flow is considered a pre-requisite for the induction of advanced vascular lesions in pulmonary arterial hypertension in congenital heart defects. The aim of the present study was to characterise the effects of increased pulmonary flow induced by an aortocaval shunt in the monocrotaline rat model for pulmonary hypertension in terms of survival, haemodynamics, pathology and histology.Male Wistar rats were injected with monocrotaline followed by the creation of an abdominal aortocaval shunt. Animals were sacrificed when displaying symptoms of weight loss or dyspnoea, 4-5 weeks after the creation of the shunt.Echocardiography identified increased ventricular dimensions in shunted rats and right ventricular hypertrophy in monocrotaline-treated rats. At similar pulmonary artery pressures, shunted monocrotaline rats displayed higher morbidity and mortality, increased pulmonary-to-systemic artery pressure ratios and increased right ventricular hypertrophy compared with nonshunted monocrotaline rats. Histological assessment demonstrated increased number and diameter of pre-acinar pulmonary arteries. Intra-acinar vessel remodelling and occlusion occurred to a similar extent in shunted and nonshunted monocrotaline rats.In conclusion, increased pulmonary blood flow in monocrotaline-induced pulmonary hypertension is associated with increased morbidity, mortality, and unfavourable haemodynamic and cardiac effects. These effects could be attributed to more pronounced right heart failure rather than to altered intra-acinar pulmonary vessel remodelling.

Een neonaat wordt beschreven met een ernstig verlopen enterovirusinfectie die restloos herstelde, aansluitend aan intensieve ondersteunende therapie, immunoglobulinen en pleconaril, een nog niet geregistreerd anti-picornavirusmiddel. De laatste ontwikkelingen met betrekking tot de diagnostiek en behandeling van enterovirusinfecties in het algemeen worden besproken en er wordt een kritische blik geworpen op het gevoerde beleid.

Background: Both pulmonary hypertension and pulmonary overflow are associated with functional and structural changes of the pulmonary arterial wall. Current techniques to evaluate the pulmonary vasculature neglect the pulsatile nature of pulmonary flow. Study objectives: To determine whether the dynamic properties of the pulmonary arterial wall are altered in patients with abnormal pulmonary hemodynamics due to congenital heart defects, and whether these changes are associated with the progression of pulmonary vascular disease (PVD). Patients and methods: In 43 children with PVD due to congenital heart defects and 12 control subjects, pulmonary arterial pulsatility (the relative increase in vessel area during the cardiac cycle) and distensibility (the inverse of the stress/strain elastic modulus) were determined with intravascular ultrasound. Results were correlated with clinical and hemodynamic parameters. Results: Pulsatility correlated with pulmonary pulse pressure (p < 0.001), pulmonary-to-systemic vascular resistance ratio (PVR/SVR) [p = 0.001], and hemoglobin concentration (p = 0.01). However, when corrected for these variables, pulsatility did not differ between patients and control subjects. In contrast, arterial wall distensibility decreased with the severity of PVD and correlated independently with pulmonary-to-systemic arterial pressure ratio (p < 0.001) and PVR/SVR (p = 0.03), and with hemoglobin concentration (p < 0.01). Adjusted for hemodynamic variables, distensibility was still decreased in patients with PVD compared to control subjects. Conclusions: These results demonstrate that pulmonary arterial wall distensibility is progressively decreased in PVD; moreover, this decreased distensibility is, in part, related to increased distending pressure as a result of pulmonary hypertension but also, in part, to stiffening of the arterial wall during the disease process. Arterial wall distensibility may be of additional value in the evaluation of pulmonary vasculature and ventricular workload.

Cryopreserved human heart valves are used for valve replacement in patients with congenital or acquired heart disease. Although no blood group or human leukocyte antigens (HLA) matching is performed and no immunosuppression is administered, the clinical results are relatively good. After valve replacement, the majority of the patients develop HLA antibodies, whereas a smaller group of patients shows valve-related events at the long term after right ventricular outflow tract reconstruction. Therefore, we hypothesized that not the mere presence, but rather the titers of antidonor HLA antibodies may be related to valve allograft failure. The presence and specificity of HLA class I antibodies were determined by complement-dependent microlymphocytotoxicity (CDC) test in longitudinally taken peripheral blood samples of 35 valve allograft recipients. In eight patients with an antibody response specific against donor-HLA class I, the titers were measured by this CDC method after stepwise dilution of the plasma. Panel reactive antibodies of more than 10% were found in 31 of 35 (89%) valve allograft recipients. From these 31 patients, 24 (77%) developed donor-specific HLA class I antibodies. All eight selected patients had detectable donor-specific antibody titers, ranging from 1:2 to 1:8,000. Two donor valve recipients before retransplantation had (donor-specific) HLA antibodies and showed high titers of 1:256 and 1:8,000 shortly after the second allograft valve replacement, which was associated with an early graft failure in the latter patient. We conclude that transplantation of cryopreserved human heart valve allografts leads to a broad and strong humoral response, which is probably the result of a lack of immunosuppressive therapy after valve transplantation. Patients receiving a second or following valve allograft appeared to be sensitized and developed early and high allo-antibody titers after second valve allograft implantation. Valve failure was diagnosed in a patient with extremely high titers. These findings suggest that preoperative cross-matching may identify patients with high donor-specific HLA antibody titers and may reduce the risk for early recurrent graft failure.

De prevalentie van aangeboren hartafwijkingen bij meisjes geboren met het syndroom van Turner (ts) is hoog, volgens de literatuur ongeveer 20 tot 25%. Hierbij komen vooral de obstructieve afwijkingen van de linker harthelft voor. Ook dilatatie van de aortawand met kans op dissectie en ruptuur wordt vaker gerapporteerd, hoewel harde gegevens over de prevalentie ontbreken. Aangeraden wordt om meisjes met ts zo snel mogelijk cardiologisch te onderzoeken als de diagnose is gesteld. Is op jonge leeftijd geen aangeboren afwijking aanwezig, dan wordt geadviseerd het cardiologische onderzoek te herhalen tijdens de puberteit. Vervolgens moet het aortaonderzoek iedere 3 tot 5 jaar worden herhaald, maar zeker voor en tijdens een geplande zwangerschap. Hypertensie komt bij ongeveer 25% van de meisjes met ts voor. Geregelde bloeddrukcontrole is dus gewenst. Een nadelig effect van de groeihormoonbehandeling op de hartspier is tot op heden niet aangetoond, maar langetermijnonderzoek hiernaar is zeker noodzakelijk.

Objective: Valvotomy and the autograft procedure are the most common surgical treatment options for children with valvular aortic stenosis. We evaluated the results of these surgical procedures in our institution. Methods: Retrospective analysis was done of all patients presenting with aortic stenosis and operated upon before the age of 18. In 11 patients a valvotomy was performed and in 36 an autograft procedure. Results: There was no hospital mortality. Mean follow-up in the valvotomy group was 4.8 years (SD 3.3), in the autograft group 4.5 years (SD 3.3). During follow-up one patient died suddenly 2 months after valvotomy. Two patients in the autograft group died (not valve-related). After valvotomy three patients underwent a balloon valvotomy, in one followed by an autograft procedure and one patient had a repeat valvotomy. In the autograft group one patient was reoperated for severe aortic regurgitation and moderate pulmonary stenosis. At last echocardiography after valvotomy (eight remaining patients) in only two patients (25%) no aortic stenosis or regurgitation was present. In the remaining six patients aortic stenosis is mild in two and moderate in three, including one with moderate aortic regurgitation. In one patient without stenosis, moderate aortic regurgitation was seen. No pulmonary stenosis or regurgitation is present. Echocardiography after autografting (33 remaining patients) showed no aortic stenosis. Aortic regurgitation was mild in seven patients, moderate in two, severe in one. Pulmonary stenosis was present in two patients (16%). Pulmonary regurgitation was mild in three patients and moderate in one. Conclusions: In selected patients with valvular aortic stenosis who are beyond infancy, valvotomy may be adequate and may postpone further surgery for a significant length of time. After valvotomy the main problem is residual aortic stenosis while after autografting a shift occurs to aortic regurgitation and problems related to the pulmonary valve. Careful clinical and echocardiographic follow-up is therefore warranted in young patients after the autograft procedure. q 2001 Elsevier Science B.V. All rights reserved.

Between July 1996 and July 1998, 34 patients (female n = 16, male n = 18) were scheduled for catheter--interventional occlusion (ASDO) of an atrium septum defect of secundum type (ASD II). Median age was 7.9 years (2.5-54.6), weight 23.1 kg (9-97). 9 defects were closed with "Angel Wings" (AW) and 25 ASD occlusions were attempted with "CardioSeal" (CS). 30 patients had simple ASD II, 3 persisting foramen ovale with suspected paradoxal cerebral embolization and 1 significant residual shunt at atrial level after corrective heart surgery for interrupted aortic arch type B. ASDO was successful in 31/34 cases (91%). One CS was removed surgically due to significant left to right shunt after release and two CS devices were withdrawn back into the sheath. Median ASD diameter was 11.9 mm (6-16), balloon occlusive diameter was 15 mm (6-20) and median left to right shunt was 40% (6-64%). On follow up minimal left to right shunt was seen in 5/31 patients (16%). In selected patients catheter--interventional ASDO may be a good alternative to surgical ASD closure.

Objective: To assess the effects of long-term growth hormone (GH) treatment for short stature on left ventricular (LV) dimensions and systemic blood pressure (BP) in girls with Turner's syndrome without clinically relevant cardiac abnormalities. Study design: LV dimensions measured by echocardiography and systemic BP were assessed before and during 7 years of GH treatment in 68 girls with Turner's syndrome participating in a randomized dose-response study. These previously untreated girls, age 2 to 11 years, were randomly assigned to 1 of 3 GH dosage groups: group A, 4 IU/m 2 /d; group B, first year 4 IU/m 2 /d, thereafter 6 IU/m 2 /d; group C, first year 4 IU/m 2 /d, second year 6 IU/m 2 /d, thereafter 8 IU/m 2 /d. After the first 4 years, girls ≥12 years of age began receiving 17β-estradiol, 5 μg/kg body weight per day, for induction of puberty. Results: At baseline the LV dimensions of almost every girl were within the normal range, and the mean SD scores were close to zero. During 7 years of GH treatment, the growth of the left ventricle was comparable to that of healthy girls. No signs of LV hypertrophy were found. Before the start of GH treatment, mean BP was within the normal range but significantly higher than in healthy control subjects. Diastolic BP and systolic BP were above the 90th percentile in 23% and 28% of the girls, respectively. After 7 years of treatment, these percentages were 14% and 36%, respectively (not significantly different from baseline). The SD score of the diastolic BP showed a small decrease after 7 years of treatment. The growth of the left ventricle and the development of BP were not different between the GH dosage groups. Conclusions: Long-term GH treatment, even at dosages up to 8 IU/m 2 /d, does not result in LV hypertrophy or hypertension in girls with Turner's syndrome. Continued observation into adulthood is recommended to monitor the further development of the relatively high BP and to ensure that GH treatment has no long-term negative effect on the heart. (J Pediatr 1999;135:470-76)

The aim of this study was to evaluate the diagnostic relevance of 3-dimensional (3D) echocardiography in the assessment of secundum atrial septum defect (ASD2).Twenty-three patients (age 2 to 58 years) with an ASD2 were studied by transthoracic (n = 9) or transesophageal (n = 14) echocardiography for the acquisition of a 3D data set before undergoing surgical repair. Qualitative (location, shape, and structure) and quantitative (largest and smallest anteroposterior and superoinferior diameters) characteristics were analyzed and compared with surgical findings. Intraobserver and interobserver variability were assessed. The gross anatomy of the ASD2, shown by the 3D images, was confirmed by the surgeon in 21 of 23 patients, but the presence of membranous or fenestrated remnants of the valvula foramina ovalis in the defect was not optimally visualized in 7 patients. Three-dimensional echocardiography revealed changes in diameter and shape of the ASD2 during the cardiac cycle. The measured largest and smallest anteroposterior diameters and their intraobserver and interobserver agreement were 274 +/- 12 mm, r = 0. 95 (P.001), r = 0.92 (P.001), and 194 +/- 9 mm, r = 0.96 (P. 001), r = 0.94 (P.001), respectively. The measured largest and smallest superoinferior diameter and their intraobserver and interobserver agreement were 304 +/- 26 mm, r = 0.90 (P.001), r = 0.97 (P.001), and 204 +/- 10 mm, r = 0.83 (P.001), r = 0.84 ( P.001), respectively. The correlation coefficient between 2D and 3D echocardiography for the largest anteroposterior and superoinferior diameter was r = 0.69 (P.001) and r = 0.68 (P =.05), respectively. The correlation coefficient between the measurements from 3D reconstructions and direct surgical measurements was r = 0.20 (P = not significant) and r = 0.57 (P.05), whereas between 2D and surgery was r = 0.50 (P.05) and r = 0.26 (P = not significant).ASD2 has a complex morphology. Three-dimensional echocardiography provides better qualitative and quantitative information on its dynamic geometry, location, and extension as compared with standard 2D echocardiography and might be useful for device selection during catheter-based closure of ASD2.

To evaluate the feasibility and accuracy of 3-dimensional (3D) echocardiography in analysis of left and right ventricular outflow tract (LVOT and RVOT) obstruction, 3D echocardiography was performed in 28 patients (age 4 months to 36 years) with outflow tract pathology. Type of lesion and relation to valves were assessed. Length and degree of obstruction were measured. Three-D data sets were adequate for reconstruction in 25 of 28 patients; 47 reconstructions were made. In 13 patients with LVOT obstruction, 3D echocardiography was used to study subvalvular details in 8, valvular in 13, and supravalvular in 1. Four of these 13 patients had complex subaortic obstruction. In 12 patients with RVOT lesions, 3D echocardiography was used to study subvalvular details in 11, valvular in 12, and supravalvular in 2. Three-dimensional reconstructions were suitable for analysis in 100% of subvalvular LVOT, 77% valvular LVOT, 100% supravalvular LVOT, 100% subvalvular RVOT, 50% valvular RVOT, and 50% supravalvular RVOT. Twenty patients underwent operation, and surgical findings served as morphologic control for thirty-four 3D reconstructions (LVOT 17, RVOT 17). Operative findings revealed an accuracy at subvalvular LVOT of 100%, valvular LVOT 90%, supravalvular LVOT 100%, subvalvular RVOT 100%, valvular RVOT 100%, and supravalvular RVOT 100%. Quantitative measurements could adequately be performed. Three-D echocardiography is feasible and accurate for analyzing both outflow tracts of the heart. Particularly, generation of nonconventional horizontal cross sections allows a good definition of extension and severity of lesions.

By 3-dimensional echocardiography, the location, relation to the aortic and tricuspid valve, and the size of the ventricular septal defect was assessed and compared with 2-dimensional echocardiography and intraoperative findings. We concluded that 3-dimensional echocardiography accurately assesses the anatomy of the ventricular septal defect, provides additional information, and can be considered a valuable preoperative diagnostic tool.

Background . Aortic root replacement with a pulmonary autograft is an alternative treatment for children with aortic valve or root disease, or both. Methods . Twenty-six patients (18 boys and 8 girls) with a mean age of 10.9 years (range, 0.3 to 16.9 years) underwent this procedures in a 7-year period. The mean follow-up period was 3.2 years (range, 0.2 to 7.5 years). Results . During follow-up 3 patients died and one autograft was replaced with a mechanical valve. The actuarial survival and actuarial event-free survival rates were 87% and 79%, respectively, at both 5 and 7 years. None of the surviving patients had complaints, and all have done well and are living normal lives. Electrocardiographic signs of myocardial ischemia and left ventricular hypertrophy were not present. Echocardiography showed autograft valve regurgitation to be absent or trivial (n = 17) or mild (n = 5). Stenosis was not present. Increasing autograft annulus diameters were noted during follow-up, but this was not related to the severity of autograft regurgitation. Left ventricular dimensions and function were within normal limits later than 1 year after the operation. Only 2 patients had a moderate pulmonary stenosis without right ventricular hypertrophy. Conclusions . The surgical results, clinical outcome, valve function, and left ventricular function in our patients have been good. This procedure is recommended as a method of aortic valve replacement in children. (Ann Thorac Surg 1997;63:1713–7)

Objective: Evaluation of surgical treatment of interrupted aortic arch (IAA) by direct anastomosis. Methods: A consecutive series of 17 infants with IAA (type A in eight patients, type B in nine) were operated upon. The mean age at arch repair was 1.0 month (range 0.2-7.7), mean weight was 3.7 kg (range 2.2-6.2). All arch repairs were done by direct anastomosis. This included a persistent arterial duct in one and a subdavian turnup in another case. The aortic reconstruction included reimplantation of a lusoric artery in three patients, patch enlargement of the ascending aorta in three and of the complete arch in one patient. The arch repair was done through a lateral thoracotomy in three patients. In 14 patients the aortic repair was part of a single-stage approach through a median sternotomy using cardiopulmonary bypass and circulatory arrest. Results: There was no operative mortality. One patient (single-stage approach) died 2 days after operation due to respiratory problems caused by tracheobronchomalacy. One patient (lateral approach) died suddenly 3 months after aortic repair and banding. Median follow up was 4.8 years (range 0.1-12.9). In five patients restenosis of the aortic arch developed, all within 1.5 years after repair. This was not correlated with the type of interruption, weight at operation, age at operation or the surgical approach. The actuarial freedom from restenosis was 61% at 5 years with a 70% confidence limit (CL 70% ) of 46-75. All restenoses were balloon dilated, but two needed redo surgery, which was done by the median approach. In three patients discrete subaortic stenosis developed. This was not correlated with the type of interruption, weight at operation, age at operation or the surgical approach. The actuarial freedom from subaortic stenosis was 68% at 5 years (CL 70% = 54-83). These stenoses were treated by enucleation, followed in one patient by a pulmonary autograft procedure for recurrent root stenosis after another year. At the end of follow up all patients were thriving well, lacked symptoms, were normotensive and had normal femoral artery pulsations. Conclusions: IAA can be treated well with primary anastomosis. Possible restenosis of the aortic arch can adequately be treated by percutaneous balloon dilatation or redo surgery if necessary. Arch repair by median single-stage approach has our preference.

This report describes the diagnosis of infra-diaphragmatic total anomalous pulmonary venous return in a fetus at 25 weeks of gestation. Abnormal venous pathways were visualized with real-time, pulsed and color Doppler ultrasound. The growth of cardiac structures, especially the left ventricle, was evaluated during subsequent ultrasound examinations.

Coarctation of the aorta and associated ventricular septal defect may be repaired simultaneously or by initial coarctation repair with or without banding of the pulmonary artery. The question is whether specific preoperative criteria can enable the surgeon to choose the optimal surgical management. Between 1980 and 1993, 80 infants younger than 3 months with coarctation and ventricular septal defect were treated surgically. In 64 infants (multistage group), simple coarctation repair was performed through a posterolateral approach, with concomitant banding of the pulmonary artery in 10 infants. Twenty ventricular septal defects were closed as a secondary procedure and four were closed as a tertiary procedure. Sixteen infants (single-stage group) underwent one-stage repair through an anterior midline approach. The total in-hospital mortality rate was 7.5%. Freedom from recoarctation after 5 years was 91.3% in the multistage group versus 60.0% in the single-stage group (p = 0.018). Freedom from secondary ventricular septal defect treatment in the multistage group after 5 years was 40.7%, versus 100% in the single-stage group (p = 0.016). Thirty-seven ventricular septal defects (47.8%) closed spontaneously. In particular, the preoperative left-to-right shunt and extension of the perimembranous VSD into the inlet or outlet were risk factors for the need for eventual surgical ventricular septal defect closure after initial coarctation repair. On the basis of these two risk factors, the probability of the need for eventual surgical treatment of ventricular septal defect after initial coarctation repair can be calculated. This policy offers a well-considered choice between single-stage and multistage repair, weighing the risk of secondary ventricular septal defect treatment versus the risk of recoarctation. Finally, the number of surgical procedures per infant will be as low as possible. (J THORAC CARDIOVASC SURG 1996;111:168-75)

Objective. Evaluation of allograft reconstruction of the right ventricular outflow tract (RVOT). Methods. From 1986 to April 1995, 201 allografts (146 pulmonary, 55 aortic) were implanted in 189 patients for conduit reconstruction of the RVOT in congenital heart disease or in the pulmonary autograft procedure. The mean age at allograft implantation was 16 years (range 2 weeks - 54 years). The primary diagnoses of these patients were truncus arteriosus (n=19, 10%), transposition of the great arteries (TGA) with ventricular septal defect (VSD) and pulmonary atresia (PA) or stenosis (PS) (n= 14, 7%), PA with VSD (n = 26, 14%), PA or PS with intact septum (n = 7, 4%), tetralogy of Fallot (n = 44, 23%), corrected TGA with PA or PS (n = 11, 6%), tricuspid atresia (n = 9, 5%), aortic valve pathology for pulmonary autograft procedure (n = 55, 29%), and miscellaneous (n =4, 2%). The allograft implantation was a reoperation in 54 patients (29%). Results. The mean follow-up was 2.5 years (range 4 weeks-9 years). Six patients died in hospital (3.2%). Patient survival at 5 years was 91% (95% CL 86-95%). Freedom from all valve-related events (2 deaths, 17 reoperations, one endocarditis), as determined during reoperation or autopsy at 5 years was 78% (95% CL 65-86%). Freedom from structural allograft failure was 83% (2 deaths, Allografts implanted for congenital right heart defects failed earlier than allografts used for pulmonary auto- graft procedures (P= 0.05). Aortic allografts showed structural failure more often than pulmonary allografts (P=0.05). There were more valve- more often than pulmonary allografts related events in patients of a younrelated at implantation (P= 0.02) and in those allograft valves from younger donors (P=0.004). Conclusions. Allograft RVOT reconstruction is an adequate surgical therapy. The allograft should preferably be pulmonary. A younger age at implantation is a risk factor for allograft failure. Donor age may be a thus-far underestimated risk factor for allograft degeneration.

The ability to assess the pulmonary vasculature in pulmonary vascular disease by hemodynamic or histologic evaluation is limited. We sought to determine the feasibility of intravascular ultrasound techniques in infants and children and to assess simultaneously the morphology and dynamics of pulmonary arteries. Patients were seen in the Department of Pediatrics, Division of Pediatric Cardiology, Sophia Children's Hospital, Rotterdam, The Netherlands. We performed intravascular ultrasound imaging in 11 pediatric patients with congenital heart disease undergoing cardiac catheterization. Luminal diameter, area, and pulsatility were determined at two to five sites in the pulmonary branches. Pulmonary vascular reaction to 100% oxygen inhalation was studied. Patients weighed 4.1-51.0 kg (21.8 + 16.3 kg, mean + SD). Luminal diameters, areas, and pulsatilities could be determined reproducibly in arteries with diameters from 1.6 to 9.3 mm. In total 39 sites were studied in 11 patients. Pulsatility was related to vessel size (r = 0.81), although a substantial interindividual variation was present. After 100% oxygen inhalation, pulsatility increased in all arteries (from 20.0 2 3.3% to 25.9 + 2.9%,p < 0.05), and vasodilatation could be directly visualized, most prominently in the smallest arteries (percentage change in diameter, mean 7.4 + 2.8% versus -2.8 2 3.1% in the largest arteries, p < 0.001). Measurement of wall thickness was not feasible, but specific changes in the appearance of the wall structure could be recognized in a patient with severely elevated pulmonary vascular resistance. The specific advantages of intravascular ultrasound in assessing pulmonary vascular disease are discussed. We conclude that intravascular ultrasound imaging of the pulmonary vasculature is feasible in infants and children and provides a unique opportunity to assess directly pulmonary dynamics in vivo. Therefore, it may be a valuable tool in evaluating the pulmonary vasculature and its responses to normal and pathologic conditions. (Pediatr Res 38

Between September 1988 and February 1993, 14 patients whose ages ranged from.3 months to 16 years (mean 11.1 ± 4.3 years) underwent replacement of the aortic root with the autologous pulmonary root for aortic valve disease. The follow-up was 4 years (cumulative total of 25.2 patient-years). There was no early mortality. Late mortality (one patient) was 7.1 % (95% confidence limits 0 % to 21 %). This patient had juvenile rheumatoid arthritis and died of consequent congestive heart failure with autograft failure 6 months after operation: Event-free survival after 4 years was 78.6% (95% confidence limits 50% to 95%). One patient was reoperated on because of autograft failure caused by a relapse of rheumatic fever. One patient operated on for critical neonatal aortic stenosis has subnormal exercise tolerance because of restrictive cardiomyopathy and pulmonary homograft regurgitation. The other 12 patients were in New York Heart Association functional class I at the end of follow-up. There was no prevalence of bacterial endocarditis. There were no signs of primary structural degeneration of the pulmonary autograft. During follow-up, in eight patients, increased anulus diameter of the pulmonary autograft could be demonstrated by precordial two-dimensional echocardiography, suggesting growth of the autograft. Our experience shows that aortic root replacement with the pulmonary autograft can be done with low mortality and morbidity in children with aortic valve disease. The operation seems to be contraindicated in children with juvenile rheumatoid arthritis because of the risk of recurrence of rheumatic disease in the autograft: The pulmonary autograft has also been shown to be susceptible to recurrence of rheumatic inflammation in children with a history of acute rheumatic fever. Despite pulmonary autograft replacement of the aortic valve in infants with critical valvular aortic stenosis and endocardial fibroelastosis, clinical results may be poor. Growth of the autograft is suggested by echocardiography follow-up. We consider aortic root replacement with the pulmonary autograft the procedure of choice in children who require aortic valve replacement.

Patients who have undergone a Fontan-type operation usually have an elevated systemic venous pressure. To determine the sequelae of this nonphysiologic condition, we evaluated 66 patients 1 to 14 years after a Fontan-type operation. Fifty-one patients were apparently in good clinical condition, and 15 patients had symptoms and were restricted in their daily life. Bicycle exercise capacity, tested in 41 patients, ranged from 50% to 110% (mean 85%) of the predicted value for length. In 16 patients, a decreased capacity (< 85%) was, among others, related to arrhythmias and the presence of protein-losing enteropathy. A 24-hour ambulatory electrocardiogram was available in 56 patients and found to be normal in 32 (57%) patients. Arrhythmias were present in 21 patients, six of whom had symptoms. Three patients had previous pacemaker implantation. One or more abnormalities in liver enzyme and function tests were present in 40 patients (61%) and in coagulation factors in 46 patients (69%). The most pronounced was a protein C deficiency, a known thrombotic risk factor, present in 41 patients. The occurrence of arrhythmias increased with time of follow-up (p < 0.004), the occurrence of protein C deficiency decreased with time (p < 0.0001), and the occurrence of abnormal liver enzyme and function tests was not related to time of follow-up. With regard to age at operation, arrhythmias did not occur in patients who underwent operation at a mean age of 4 +/- 1.9 years (standard deviation), in contrast to patients who underwent operation at a mean age of 7.6 +/- 4 years (standard deviation) (p < 0.001). The occurrence of the two other types of sequelae was not related to the age at operation. With regard to the type of operation, only patients with a valved right atrium-to-pulmonary artery connection had a higher prevalence of arrhythmias than patients with a nonvalved or direct right atrium-to-pulmonary artery connection (p < or = 0.001). The latter patients also had a higher prevalence of protein C deficiency (p < or = 0.001). No relationship was found among the other types of operation, the underlying structure, or the hemodynamic condition measured at rest and the presence of arrhythmias, abnormal liver enzyme and function tests, or protein C deficiency. This point survey shows that even patients with an apparently good clinical condition are at risk for arrhythmias, abnormal liver enzyme and function tests, and coagulation factor abnormalities. Serial statement of affairs is recommended to ensure that adequate preventive measures can be taken.

Severe thromboembolism occurred in 3 of 37 patients who had undergone Fontan-type operations for correction of congenital heart defects several months to years after the operation. The patients were screened for coagulation factor abnormalities to find out whether known prothrombotic risk factors could explain the high frequency of thromboembolism. 63 abnormalities were found in 24 of the 37 patients. The commonest and most pronounced abnormality was deficiency of protein C, a known risk factor. Concentrations of antithrombin III and factors II and X were significantly lower in protein-C-deficient patients than in those with normal protein C concentrations. These findings suggest that the high thrombotic risk in these patients is caused or at least associated with an imbalance between procoagulant and anticoagulant factors.

Pulmonary hypertension, and consequently right ventricular failure, complicates several congenital heart defects. Although intervention in the prostacyclin-thromboxane ratio is known to improve outcome, the underlying mechanism is not clear. Therefore, effects of acetyl salicylic acid and iloprost are studied in an animal model for flow-associated pulmonary hypertension. Male Wistar rats with flow-associated pulmonary hypertension, an aortocaval shunt in addition to monocrotaline induced pulmonary hypertension, were treated with low-dose aspirin (25 mg/kg/day) or iloprost (72 microg/kg/day). Effects on pulmonary hemodynamics and pulmonary vascular remodeling as well as right ventricular hemodynamics and remodeling were evaluated. Ninety percent (n=7/8) of the untreated pulmonary hypertensive rats developed dyspnea and pleural fluid, whereas this was seen in 50% (n=4/8, ns) and 10% (n=1/8, P

Very preterm infants who develop bronchopulmonary dysplasia are often treated with dexamethasone (DEXA) to wean them from the ventilator. As DEXA has growth-suppressive and catabolic effects, which might have long-term consequences on growth and organ development, we investigated whether high-dose GH treatment could overcome these effects. In a randomized, double-blind, placebo-controlled trial, 30 ventilated very low birth weight infants were assigned to receive either GH or placebo treatment after start of DEXA. DEXA was given for 24 d (starting dose 0.5 mg (.) kg(-1) d tapering off every third day). Simultaneously, high-dose GH (0.3 mg (.) kg(-1) (.) d(-1)) or placebo was administered during 6 wk. During high-dose DEXA treatment (dose 0.5-0.3 mg (.) kg(-1) (.) d(-1)), no gain in head circumference, weight, crown-heel length, and knee-heel length occurred in the GH and placebo groups. Growth during the 6-wk study period was not different between the GH and the placebo groups. Two patients in the placebo group died, but the number and the severity of adverse effects was not statistically different between the GH and placebo groups. In conclusion, high-dose GH treatment did not improve growth in DEXA-treated very preterm infants and thus cannot be recommended to prevent growth failure in these infants. During high-dose DEXA, a complete growth arrest occurred, including stunting of head growth. Growth in head circumference and weight with lower dose DEXA was comparable to growth after discontinuation of DEXA.

Background Left-sided atrioventricular valve regurgitation is the main indication for reoperation in patients after repair of both partial and complete atrioventricular septal defect. Until now, the timing for reoperation is difficult. We sought to determine the outcome of severe residual left-sided atrioventricular valve regurgitation, either medically treated or reoperation. In this regard risk factors were determined for severe residual left-sided atrioventricular valve regurgitation and reoperation, and the most appropriate strategy for patients with postoperative severe left-sided atrioventricular valve regurgitation was identified. Methods Retrospective review of clinical, operative, and echocardiographic data was performed. From 1990 until 2001 164 patients underwent correction of their atrioventricular septal defect. Results Five patients died in the immediate postoperative period, and 2 patients were lost to follow-up. During follow-up (median, 66 months; range, 9 months to 12 years), 30 patients (19%) had severe left-sided atrioventricular valve regurgitation. Sixteen patients had severe left-sided atrioventricular valve regurgitation in the immediate postoperative period; 4 of them showed spontaneous regression to near-normal valve function during follow-up. Fourteen patients exhibited left-sided atrioventricular valve regurgitation during follow-up; 8 of them remained stable with medication only. Fifteen of the 30 patients with severe left-sided atrioventricular valve regurgitation underwent reoperation. A significant risk factor for the development of severe left-sided atrioventricular valve regurgitation and reoperation was the presence of preoperative severe left-sided atrioventricular valve regurgitation. Conclusions Severe left-sided atrioventricular valve regurgitation develops in a significant number of patients after correction of atrioventricular septal defect, and preoperative severe left-sided atrioventricular valve regurgitation is an important risk factor. Although reoperation usually results in good valve function, spontaneous regression after the immediate postoperative period is possible and should be given a fair chance.

Both pulmonary hypertension and pulmonary overflow are associated with functional and structural changes of the pulmonary arterial wall. Current techniques to evaluate the pulmonary vasculature neglect the pulsatile nature of pulmonary flow.To determine whether the dynamic properties of the pulmonary arterial wall are altered in patients with abnormal pulmonary hemodynamics due to congenital heart defects, and whether these changes are associated with the progression of pulmonary vascular disease (PVD).In 43 children with PVD due to congenital heart defects and 12 control subjects, pulmonary arterial pulsatility (the relative increase in vessel area during the cardiac cycle) and distensibility (the inverse of the stress/strain elastic modulus) were determined with intravascular ultrasound. Results were correlated with clinical and hemodynamic parameters.Pulsatility correlated with pulmonary pulse pressure (p0.001), pulmonary-to-systemic vascular resistance ratio (PVR/SVR) [p = 0.001], and hemoglobin concentration (p = 0.01). However, when corrected for these variables, pulsatility did not differ between patients and control subjects. In contrast, arterial wall distensibility decreased with the severity of PVD and correlated independently with pulmonary-to-systemic arterial pressure ratio (p0.001) and PVR/SVR (p = 0.03), and with hemoglobin concentration (p0.01). Adjusted for hemodynamic variables, distensibility was still decreased in patients with PVD compared to control subjects.These results demonstrate that pulmonary arterial wall distensibility is progressively decreased in PVD; moreover, this decreased distensibility is, in part, related to increased distending pressure as a result of pulmonary hypertension but also, in part, to stiffening of the arterial wall during the disease process. Arterial wall distensibility may be of additional value in the evaluation of pulmonary vasculature and ventricular workload.

2-D Doppler echocardiography was used to assess the occurrence of haemodynamic abnormalities in 45 asymptomatic patients, aged 4 to 16 years (median 7.4) after a Mustard operation for transposition of the great arteries. The findings were compared with those derived from cardiac catheterization. Thirty-five cardiac lesions were correctly diagnosed by 2-D Doppler echocardiography in 23 patients, but on six occasions, minor abnormalities were missed. 2-D Doppler echocardiography demonstrated systemic venous pathway obstruction of more than 3 mmHg at cardiac catheterization in nine patients, and in five of the six patients with pulmonary venous channel obstruction. A left ventricular outflow tract obstruction (pressure difference greater than 15 mmHg) was diagnosed correctly by Doppler echocardiography in seven patients. Baffle leakage was found in two patients with a left to right shunt of 25% or more of pulmonary blood flow, but was missed in five out of nine patients with small shunts. Tricuspid regurgitation was well defined in eight patients. The absence of symptoms and a routine examination after a Mustard operation do not rule out haemodynamic abnormalities. However, these, with the possible exception of minor baffle leakage, can be detected by 2-D Doppler echocardiography.

To assess the effects of long-term growth hormone (GH) treatment for short stature on left ventricular (LV) dimensions and systemic blood pressure (BP) in girls with Turner's syndrome without clinically relevant cardiac abnormalities.LV dimensions measured by echocardiography and systemic BP were assessed before and during 7 years of GH treatment in 68 girls with Turner's syndrome participating in a randomized dose-response study. These previously untreated girls, age 2 to 11 years, were randomly assigned to 1 of 3 GH dosage groups: group A, 4 IU/m(2)/d; group B, first year 4 IU/m(2)/d, thereafter 6 IU/m(2)/d; group C, first year 4 IU/m(2)/d, second year 6 IU/m(2)/d, thereafter 8 IU/m(2)/d. After the first 4 years, girls/=12 years of age began receiving 17beta-estradiol, 5 microg/kg body weight per day, for induction of puberty.At baseline the LV dimensions of almost every girl were within the normal range, and the mean SD scores were close to zero. During 7 years of GH treatment, the growth of the left ventricle was comparable to that of healthy girls. No signs of LV hypertrophy were found. Before the start of GH treatment, mean BP was within the normal range but significantly higher than in healthy control subjects. Diastolic BP and systolic BP were above the 90th percentile in 23% and 28% of the girls, respectively. After 7 years of treatment, these percentages were 14% and 36%, respectively (not significantly different from baseline). The SD score of the diastolic BP showed a small decrease after 7 years of treatment. The growth of the left ventricle and the development of BP were not different between the GH dosage groups.Long-term GH treatment, even at dosages up to 8 IU/m(2)/d, does not result in LV hypertrophy or hypertension in girls with Turner's syndrome. Continued observation into adulthood is recommended to monitor the further development of the relatively high BP and to ensure that GH treatment has no long-term negative effect on the heart.