An early innate response underlies severe influenza-induced exacerbations of asthma in a novel steroid-insensitive and anti-IL-5-responsive mouse model.

BACKGROUND: Acute worsening of asthma symptoms (exacerbation) is predominantly triggered by respiratory viruses, with influenza causing the most severe exacerbations. The lack of an adequate animal model hampers mechanistic insight and the development of new therapeutics. AIM: We developed and characterized a robust, consistent, and reproducible mouse model of severe exacerbation of chronic allergic asthma. METHODS: Chronic allergic airway inflammation was induced following a house dust mite (HDM) sensitization protocol. HDM-sensitized mice and controls were infected with influenza virus A/X31 H3N2 and either or not treated with inhaled fluticasone propionate (FP), systemic corticosteroids (Pred), or anti-IL-5. Mice were killed at different time points after infection: Cellular accumulation and cytokines levels in the airways, PenH as a measure of airway hyper-responsiveness (AHR), and lung histology and viral replication were assessed. RESULTS: Infection with low-dose A/X31 H3N2 led to prolonged deterioration of lung function, aggravated mucus production, peri-vascular, peri-bronchial, and allergic inflammation that was unresponsive to inhaled corticosteroids, but responsive to systemic corticosteroids. The exacerbation was preceded at 14 h after virus exposure by a marked innate, but no Th2 and Th1 response subsequently followed by enhanced numbers of eosinophils, neutrophils, dendritic, and T cells into the lung lumen, parenchyma, and draining lymph nodes in HDM-sensitized mice. Anti-IL-5 treatment attenuated eosinophils and prevented the X31-induced exacerbation. CONCLUSIONS: Together, these findings indicate that an early innate response that involves eosinophils underlies the exacerbation. This model recapitulates all major features of severe asthma exacerbations and can serve to discern driving mechanisms and promote the development of novel therapeutics.

The role of increased pulmonary blood flow in pulmonary arterial hypertension.

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.

Is there a place for pediatric valvotomy in the autograft era?

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.

Right ventricular outflow tract reconstruction with an allograft conduit.

BACKGROUND: Allograft conduits are used for reconstruction of the right ventricular outflow tract in patients with congenital heart disease and in the pulmonary autograft procedure. A retrospective evaluation of our experience with the use of allograft conduits for reconstruction of the right ventricular outflow tract was conducted. METHODS: Between August 1986 and March 1999, 316 allografts (246 pulmonary, 70 aortic) were implanted in 297 patients for reconstruction of the right ventricular outflow tract. Main diagnostic groups were aortic valve pathology (n = 112, 35%), tetralogy of Fallot (n = 71, 22%), and pulmonary atresia with ventricular septal defect (n = 46, 14%). Kaplan-Meier analyses were done for survival, valve-related reoperation, and valve-related events. In addition, Cox regression analysis was used for evaluation of potential risk factors. RESULTS: Mean age at operation was 18 years (range, 7 days to 61 years). Mean follow-up was 4 years (range, 2 days to 12 years). Twelve patients (4%) died within 30 days after operation. Patient survival was 90% (95% confidence interval [CI], 86% to 94%) at 5 years and 88% (95% CI, 83% to 94%) at 8 years. Twenty-four reoperations were required for allograft dysfunction in 23 patients; 21 allografts were replaced. Freedom from valve-related reoperation was 91% (95% CI, 86% to 95) at 5 years and 87% (95% CI, 81% to 93%) at 8 years. Twenty-nine valve-related events were reported (2 deaths, 24 reoperations, 2 balloon dilatations, and 1 endocarditis). Freedom from valve-related events was 90% (95% CI, 85% to 94%) at 5 years after implantation, and 84% (95% CI, 77% to 91%) at 8 years. Risk factors for accelerated allograft failure were extra-anatomic position of the allograft (p = 0.03; hazard ratio, 9.7) and the use of an aortic allograft (p = 0.02; hazard ratio, 2.4). CONCLUSIONS: Right ventricular outflow tract reconstruction with an allograft conduit has good medium-term results, although progression of allograft degeneration is noted. Aortic allografts should preferably not be used for reconstruction of the right ventricular outflow tract.

Recombinant human alpha-glucosidase from rabbit milk in Pompe patients.

Pompe's disease is a fatal muscular disorder caused by lysosomal alpha-glucosidase deficiency. In an open-label study, four babies with characteristic cardiomyopathy were treated with recombinant human alpha-glucosidase (rhGAA) from rabbit milk at starting doses of 15 mg/kg or 20 mg/kg, and later 40 mg/kg. The enzyme was generally well tolerated. Activity of alpha-glucosidase normalised in muscle. Tissue morphology and motor and cardiac function improved. The left-ventricular-mass index decreased significantly. We recommend early treatment. Long-term effects are being studied.

The effects of long-term growth hormone treatment on cardiac left ventricular dimensions and blood pressure in girls with Turner's syndrome. Dutch Working Group on Growth Hormone.

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 17beta-estradiol, 5 microg/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.

Three-dimensional echocardiography enhances the assessment of ventricular septal defect.

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.

Secundum atrial septal defect is a dynamic three-dimensional entity.

BACKGROUND: 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). METHODS AND RESULTS: 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). CONCLUSIONS: 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.

Use of three-dimensional echocardiography for analysis of outflow obstruction in congenital heart disease.

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.

[Interventional catheter occlusion of the atrial septal defect of the secundum type--experiences with "CardioSeal" and "Angel Wings"]. / Katheterinterventioneller Verschluss des Vorhofseptumdefektes vom Sekundumtyp--Erfahrungen mit "CardioSeal" und "Angel Wings".

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.

Clinical outcome and left ventricular function after pulmonary autograft implantation in children.

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.

Allograft root on closed pulmonary valve for subaortic obstruction in double-inlet left ventricle with transposition of the great arteries.

BACKGROUND: Until recently closure of the pulmonary valve during staged Fontan-type palliation in the setting of double-inlet left ventricle with an unrestrictive or adequately enlarged ventricular septal defect and transposition of the great arteries with the aorta on a left-sided outflow chamber was regarded as an appropriate part of surgical treatment. Lately, however, an increased incidence of subsequent subaortic obstruction has been described in this regard. METHODS: Allograft root placement on the previously closed pulmonary orifice in combination with a modified Damus-Kaye-Stansel procedure is described to create an unobstructed outflow from the main ventricle to the systemic circulation. This procedure was done in 3 patients. One root placement was combined with the construction of the bidirectional superior cavopulmonary connection, one was done as an intermediate step before completion of the cavopulmonary connection, and one was combined with completion of total cavopulmonary connection. RESULTS: Immediate relief of the subaortic obstruction was achieved in all 3 patients. Ventricular hypertrophy, echocardiographically assessed by diastolic posterior wall thickness, regressed to normal in all 3 within 6 to 12 months. CONCLUSIONS: Allograft root placement on the reopened pulmonary orifice in double-inlet left ventricle with a ventricular septal defect and transposition of the great arteries appears technically feasible and functionally adequate on short-term follow-up. This procedure should result in regression of ventricular hypertrophy to allow eligibility for a Fontan-type palliation again. To what extent possible failure of the allograft increases the risk of an adverse outcome of this palliation may be a matter of concern.

Repair of aortic arch interruption by direct anastomosis.

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 subclavian 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 (CL70%) 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 (CL70% = 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.

In utero diagnosis of infra-diaphragmatic total anomalous pulmonary venous return.

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.

Decision making for the surgical management of aortic coarctation associated with ventricular septal defect.

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.

Allograft reconstruction of the right ventricular outflow tract.

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 arterious (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, 12 reoperations, 95% CL 70-90%). Allografts implanted for congenital right heart defects failed earlier than allografts used for pulmonary autograft procedures (P = 0.05). Aortic allografts showed structural failure more often than pulmonary allografts (P = 0.05). There were more valve-related events in patients of a younger age 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.

Two decades of transesophageal phased array probes.

After its introduction about two decades ago, transesophageal echocardiography (TEE) has rapidly evolved into an important diagnostic feature for the cardiologist, since it offers anatomic and hemodynamic information which cannot be obtained precordially. Part of this success was due to the developments in transducer technology which resulted in smaller probes with progressively better imaging qualities. A short review of past, recent and future developments of TEE phased array probes, in particular those at the Erasmus University in Rotterdam, will be given. Furthermore, this article discusses basic parameters of the transducer dictating image quality such as centre frequency, array aperture and focusing illustrated with several simulations. The simulations show that a poor design of the transducer will limit the resolution and will give artefacts in the two-dimensional image.

Evaluation of the pulmonary vasculature and dynamics with intravascular ultrasound imaging in children and infants.

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 +/- 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 +/- 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.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolated pulmonary vein stenosis in complex congenital heart disease, simulating cor triatriatum by cardiac catheterization and transoesophageal echocardiography.

A case of localized stenosis of the lower left pulmonary vein, associated with perimembranous ventricular septal defect (VSD) and secundum atrial defect (ASD), a borderline sized mitral valve apparatus and left ventricle, is described. This final diagnosis was made at surgery, as the localized stenosis of the left pulmonary vein was misinterpreted as partial cor triatriatum by cardiac catheterization, cineangiocardiography and extensive echocardiographic studies. Surgical correction of all the defects was successful, but pulmonary vascular resistance was still increased 2 years after surgery.

Aortic root replacement with a pulmonary autograft.

A series of 42 consecutive patients with exclusively aortic root replacement using the pulmonary autograft is presented. The mean age at operation was 19.3 years (range 0.3-41.4). Two patients died in hospital (4.8%; 70% CL: 0.0-8.2). This mortality was not related to the autograft procedure. The mean follow-up time was 30 months (range 3-70; SD: 20). Late mortality consisted of two patients; in one of these severe autograft failure occurred due to chronic juvenile rheumatoid arthritis. The estimated survival rate at 4 years was 88.8% (70% CL: 83.3-94.5). Morbidity involved three patients. One had a total heart block after operation, requiring pacemaker implantation and two patients were reoperated: one for severe autograft failure due to recurrent acute rheumatic fever and the other for severe stenosis at the distal anastomosis of the pulmonary allograft. Thromboembolic complications and endocarditis were not registered. Reoperations for technical or degenerative reasons were not necessary. The estimated event-free survival rate at 4 years was 78.7% (70% CL: 71.0-86.4). Serial echocardiography (n = 28) showed a significant increase of the autograft annulus diameter of 2.9 mm (SD: 2.7). Thirty-five of the 37 patients with an autograft in situ were in NYHA class I, and 2 in class II. At last follow-up precordial color Doppler echocardiography showed moderate aortic regurgitation in one patient and no, trivial or mild aortic regurgitation in 36 patients. Stenosis of the autograft was not observed. These medium-term results are promising with respect to mortality, morbidity and functional results.(ABSTRACT TRUNCATED AT 250 WORDS)