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Biomedical subjects

J Kachaner

Publications and source records attributed to J Kachaner.

At least 55 records · Page 3Linked to original sources
PubMed1999

A mitochondrial cytochrome b mutation but no mutations of nuclearly encoded subunits in ubiquinol cytochrome c reductase (complex III) deficiency.

Ubiquinol cytochrome c reductase (complex III) deficiency represents a clinically heterogeneous group of mitochondrial respiratory chain disorders that can theoretically be subject to either a nuclear or a mitochondrial mode of inheritance. In an attempt to elucidate the molecular bases of the disease, we first determined the nucleotide sequence of three unknown subunits (9.5 kDa, 7.2 kDa, 6.4 kDa) by cyberscreening of human expressed sequence tag data bases and sequenced the 11 cDNA subunits encoding complex III in five patients with isolated complex III deficiency. No mutation in the nuclearly encoded complex III subunits was observed, but a mutation in the cd2 helix of the mitochondrial (mt) cytochrome b gene was found to alter the conformation of the bc1 complex in one patient with severe hypertrophic cardiomyopathy. The present study is highly relevant to genetic counseling as the absence of mtDNA mutations in all but one patient in our series strongly supports autosomal rather than maternal inheritance in the majority of patients with complex III deficiency.

Amino Acid Sequence↗
PubMed1999

Surgical angioplasty of the main coronary arteries in children.

OBJECTIVE: To determine the safety and efficacy of surgical angioplasty of the coronary arteries in children. METHODS: We performed 9 surgical reconstructions of the left main coronary artery and 1 of the right coronary artery ostium in 10 children (mean age 5.7 years; range 2 months-15 years). The basic diseases included the following: congenital atresia of the left coronary artery (n = 2) and atresia of the right coronary artery in a patient with an aortoventricular tunnel (n = 1); stenosis of the left main coronary artery (1) in a patient with Williams syndrome (n = 1), (2) in a patient with familial hypercholesterolemia (n = 1), (3) after the arterial switch operation for transposition of the great arteries (n = 3), (4) after reimplantation of an anomalous left main coronary artery from the pulmonary artery (n = 1), and (5) by compression after a réparation à l'étage ventriculaire procedure (n = 1). Myocardial viability was assessed by single photon emission computed tomography (thallium 201; 7/10). The coronary artery stem was enlarged with a saphenous (n = 5), a pericardial (n = 4), or a polytetrafluoroethylene patch (n = 1). RESULTS: There was 1 hospital death and 9 patients are alive (mean follow-up 46 +/- 30 months; range 12 months to 10.5 years). Eight of 9 survivors had a selective coronary artery angiogram and had normal coronary artery ostia. Two patients had stenosis of the left anterior descending coronary artery, 1 of whom underwent successful internal thoracic artery grafting. CONCLUSIONS: Surgical angioplasty of the coronary stems restores physiologic coronary perfusion and conserves bypass material. It can be performed safely in children and provides encouraging midterm results.

Adolescent↗
PubMed1999

A new strategy for the surgical treatment of aortic coarctation associated with ventricular septal defect in infants using an absorbable pulmonary artery band.

OBJECTIVES: We propose a new strategy using coarctation repair together with a polidioxanone absorbable pulmonary artery banding to limit operative risk and to spare infants with aortic coarctation subsequent operations. BACKGROUND: The alternative for the surgical management of aortic coarctation associated with ventricular septal defect (VSD) is single-stage repair versus coarctation repair with or without banding of the pulmonary artery. METHODS: Eleven infants (mean weight 2,560 +/- 1,750 g, range 1,320 to 3,800 g) underwent a coarctation repair with a polydioxanone banding. Seven had a trabecular and four a perimembranous VSD. The mean size of the VSD was 5 +/- 0.7 mm (range 4 to 7 mm). The systolic pulmonary pressure was >80% of the aortic pressure in all. The pulmonary band was tightened until the systolic pulmonary pressure fell below 50% of the aortic pressure. RESULTS: There were no hospital deaths. The reabsorption of the banding was complete after 5.7 months in all patients (3 to 6.5 months). The VSD closed completely in four infants and partially in six, in whom the pulmonary artery pressure was normal without evidence for significant left-to-right shunt. One patient with a large trabecular VSD underwent surgical closure of his defect after four months. Finally, a subsequent open-heart surgery could be avoided in 91% (10/11) of patients. CONCLUSIONS: Provided the VSD belongs to types prone to close spontaneously, this policy may reduce the number of surgical procedures per infant as well as in-hospital mortality and morbidity rates. It should be proposed as an alternative to more complex procedures.

Absorbable Implants↗
PubMed1999

[Myocardial ischemia: an unknown complication of drepanocytosis in children. Apropos of 2 case reports].

BACKGROUND: Myocardial ischemia is a severe and unknown complication in children with sickle cell anemia. CASE REPORTS: Two cases of myocardial ischemia complicated by syncope in one (8-year-old) and cardiomyopathy in the other (3-year-old) are reported. CONCLUSION: Chest pain in children with sickle cell anemia should require ECG and, in case of hypokinetic cardiomyopathy, a myocardial SPECT. More aggressive therapy of sickle cell anemia should be considered in case of documented myocardial ischemia.

Anemia, Sickle Cell↗
PubMed1999

Total cavopulmonary and atriopulmonary connections are associated with reduced heart rate variability.

AIM: To determine whether cavopulmonary connections are associated with abnormalities of heart rate variability. METHODS: Heart rate variability was studied by 24 hour Holter monitoring in 39 patients (mean (SD) age 12.2 (4.1) years) who underwent cavopulmonary connection operations (partial in 12, total in 13, and atriopulmonary in 14). Two control groups were used: 18 healthy children (11.1 (2.5) years) and 16 patients (11.7 (4.3) years) undergoing cardiovascular surgery for biventricular repair of congenital heart disease. All patients were in sinus rhythm and had normal left ventricular function. Four time domain indices were calculated: mean duration of RR intervals (RR), standard deviation of all RR intervals (SD), square root of the mean squared differences of successive RR intervals (r-MSSD), and percentage differences of successive RR intervals of > 50 ms duration (pNN50). Four frequency domain indices were calculated: total power (TP), low frequency (LF), high frequency (HF), and the LF:HF ratio. RESULTS: Heart rate variability indices were identical in the two control groups. Significantly reduced heart rate variability was found in patients with total cavopulmonary connections and atriopulmonary connections compared with the two control groups. In patients with partial cavopulmonary connections, heart rate variability was reduced compared with healthy controls. No differences in heart rate variability could be related to clinical status (New York Heart Association functional class), number of surgical interventions, or presence of right atrial enlargement. CONCLUSIONS: Patients with cavopulmonary connections have significantly reduced heart rate variability and a particularly low vagal drive.

Adolescent↗
PubMed1999

[Compromise of the cardiac autonomic nervous system in patients with Fontan-type circulation: preliminary data].

BACKGROUND: Rhythm disturbances are frequent after Fontan operations. Arrhythmias related to reduced heart rate variability (HRV) have been described in various cardiovascular diseases. METHODS: We attempted to investigate HRV in 12 patients who underwent Fontan operation (age 11.4 +/- 3 years). Results were compared to a control group of 13 children matched for age, sex and heart rate (10.4 +/- 3 years). All patients underwent 24-hour Holter monitoring. The following time domain indexes were calculated: mean duration of RR intervals, standard deviation of all RR intervals (SD), square root of the mean squared differences of successive RR intervals (r-MSSD), percentage of differences between adjacent RR intervals > 50 msec (pNN50). The following frequency domain indexes were calculated: total power (TP), low frequency (LF), high frequency (HF), LF/HF ratio. RESULTS: The following indexes were significantly reduced in Fontan patients: SD (p < 0.0001), r-MSSD (p < 0.0001), pNN50 (p = 0.0002), TP (p < 0.0001), LF (p < 0.0001), HF (p = 0.0001). LF/HF increased significantly (p = 0.04). No differences were detected according to the type of operation (cavopulmonary connection vs atriopulmonary connection) or clinical status. CONCLUSIONS: Patients with Fontan circulation had a significantly reduced HRV and particularly abnormal sympatho-vagal balance. Surgery on the caval veins and the atria alters the intracardiac ganglia that are abundant at the cavo-atrial junction and in the myocardium of the right atrium. Abnormalities of HRV in Fontan patients may act as a co-factor in the initiation of arrhythmia in these patients.

Adolescent↗
PubMed1999

[A new anatomical approach to congenital valve diseases by three-dimensional echocardiography].

Congenital valvular heart disease in childhood is often complex. Conventional echocardiography provides two-dimensional views which require mental reconstruction for three-dimensional assessment. This problem may be solved by the use of three-dimensional (3D) echocardiography which obtains images of valves comparable to those seen at surgery. This was confirmed by 4 cases of congenital valvular heart disease studied by 3D echocardiography: stenotic bicuspid aortic valve disease, parachute mitral valve and two cases of mitral regurgitation in patients with atrioventricular canal. The 3D views of the aortic valve showed the commissural opening after percutaneous balloon valvuloplasty of the bicuspid valve. The surface of the aortic orifice and the surface of the two mitral leaflets were measured from 3D reconstructions. The longitudinal 3D view analysed the extension of the single obstructive mitral papillary muscle of the parachute malformation. The 3D ventricular views allowed assessment of the extension of the cleft and the surface of the three mitral leaflets of the 2 cases of atrioventricular canal. In one of these cases, the results of surgical valvuloplasty were evaluated after 3D reconstruction of the valve. 3D echocardiography is not only a diagnostic tool for congenital heart disease but also a very useful complementary investigation for accurate evaluation of congenital valvular lesions to optimise possible valve repair.

Adolescent↗
PubMed1999

[Treatment of obstruction of prosthetic conduct by percutaneous implantation of stents].

Prosthetic conduits, with or without biological valves, are often inserted in surgical procedures to correct or palliate cardiac malformations. The principal problem is degeneration which causes variable degrees of obstruction requiring reoperation for their replacement. The aims of this study were to assess the feasibility, safety and efficacy of a non-surgical method of treating these obstructive prostheses by dilatation-implantation of a metallic vascular endoprosthesis (stenting). Thirteen patients were treated (age range 7.7 to 36 years; mean: 15 years). Eight had pulmonary atresia with a ventricular septal defect corrected by a valved conduit from the right ventricle to the pulmonary artery which became obstructive nearly 10 years later: the implantation of the stent reduced the transconduit pressure gradient in all cases except one who had not undergone closure of the septal defect in which the cyanosis was improved. There are two cases of obstruction of a modified Blalock anastomosis in which the stent revascularised the shunt with improvement in cyanosis. In the final 3 cases, the whole Fontan procedure was compromised by obstruction of a conduit incorporated in the system, and which dilatation with stenting considerably improved. The efficacy of the procedure was constant with no complications other than rupture of the balloon in 3 cases. The good results were maintained for an average of 7.3 months (range 1 to 25 months), but it was necessary to redilate one restenosed stent after 8 months. Dilatation followed by stenting in obstructive cardiovascular prostheses is a simple, safe and effective alternative to surgical reoperation.

Adolescent↗
PubMed1999

[Prenatal diagnosis of transposition of great vessels reduces neonatal morbidity and mortality].

Transposition of the great arteries (TGA) is a common malformation which sometimes has a dramatic presentation at birth but which is completely curable with early and appropriate initial management. Antenatal diagnosis of this condition may change the neonatal prognosis. The authors compared morbidity and mortality in the pre- and postoperative periods of 68 neonates with an antenatal diagnosis of TGA (foetal diagnosis) with that of 250 neonates in whom the diagnosis was made after birth (neonatal diagnosis). The delay before admission to the department was 2 +/- 2.8 hours in the foetal group and 73 +/- 210 hours in the neonatal group (p < 0.01). Severe haemodynamic distress (metabolic acidosis, multi-organ failure) were more common in the neonatal group (p < 0.01). Management on admission was identical in the two groups (p > 0.05). The preoperative mortality was 15/250 in the neonatal group (6%, 95% CI = 3-9%) compared with 0/68 in the foetal group (p < 0.05). The postoperative morbidity was comparable in the two groups (25/235 and 6/68) but the hospital stay was longer in the neonatal group (30 +/- 17 versus 24 +/- 11 days, p < 0.01). Finally, postoperative mortality was significantly higher in the neonatal group (20/235 compared with 0/68, p < 0.01) although the risk factors of death at arterial switch surgery were identical in the two groups. Therefore, antenatal diagnosis of TGA reduces neonatal morbidity and mortality in this condition. Antenatal diagnosis must be developed by the education of obstetricians. The transfer of mothers with a foetus affected by TGA to centres capable of assuming the initial management, sometimes during labour, is essential.

Female↗
PubMed1998

Prevalence of the microdeletion 22q11 in newborn infants with congenital conotruncal cardiac anomalies.

UNLABELLED: Conotruncal malformations account for about 50% of congenital heart defects diagnosed in newborns. We studied prospectively 104 patients admitted in our neonatal intensive care unit for conotruncal defects by fluorescence in situ hybridization to estimate the prevalence of the interstitial deletion in this category of congenital heart disease. Cardiac phenotypes were: truncus arteriosus (17), interrupted aortic arch (18), tetralogy of Fallot with or without pulmonary valve atresia (55), tetralogy of Fallot with absent pulmonary valves (5), ventricular septal defect with malalignment of the conal septum (9). We discovered a microdeletion 22q11 at loci D22S39 or D22S398 in 50 newborns (48%). The prevalence of this microdeletion in different groups of conotruncal defects was: truncus arteriosus 7/17, interrupted aortic arch 16/18, tetralogy of Fallot 19/55, absent pulmonary valves 2/5, and ventricular septal defect 6/9 respectively. Only two patients without any clinical or biological feature of the so called CATCH22 syndrome exhibited the deletion. Parental studies confirmed that the deletion occurred de novo in 47/50 cases (three parental microdeletions). On the other hand, recurrence of conotruncal heart defects in families of "undeleted probands" was higher than expected (13%). CONCLUSION: In 50/104 newborns with conotruncal defects, an interstitial deletion 22q11 was found. Fluorescence in Situ Hybridization should be performed in newborn infants with conotruncal defect and at least one additional manifestation of the CATCH22 phenotype.

Chromosome Deletion↗
PubMed1998

[Recommendations for the treatment of recurrent supraventricular tachycardia in infants].

AIM: The effectiveness and safety of antiarrhythmic agents, mostly digoxin and amiodarone given to prevent recurrences, were compared in 141 infants of less than 1 year (77% < 1 month) with re-entrant supraventricular tachycardia. RESULTS: Digoxin was the drug of first choice in 114 patients at a dose of 10-20 micrograms/kg/d and was effective in 74 cases (65%). Amiodarone was used as first line therapy or after failure of digoxin. It was given at a maintenance dose of 250 mg/m2/d, alone in 22 infants and together with digoxin in another 36; it was effective in 56 cases (96.5%). Early adverse events occurred in six patients receiving digoxin: ventricular fibrillation requiring cardioversion in three, two of whom had Wolff-Parkinson-White syndrome, significant sinus bradycardia in two, accidental overload in one. At further follow-up, one child treated with digoxin but having also gastroesophageal reflux, died suddenly at 3 months of age; autopsy was normal and the digoxin blood level was 3 ng/mL. Among the 58 infants who received amiodarone, there were no proarrhythmia, a slight and transient increase in TSH in six infants and only one required a short-term treatment for hypothyroidism. Prophylactic therapy was maintained for 6 to 12 months and only ten patients had recurrences in the year following withdrawal. CONCLUSION: Amiodarone was found to be safer and more effective than digoxin. No significant side-effect was demonstrated in infants receiving a short-term treatment. Amiodarone may be proposed as first line therapy for prophylaxis of re-entrant supraventricular tachycardia in infancy, especially for those patients with reentry and Wolff-Parkinson-White syndrome.

Amiodarone↗
PubMed1998

Efficiency of metabolic screening in childhood cardiomyopathies.

AIM: To estimate the efficiency of metabolic screening in children's cardiomyopathy. METHODS AND RESULTS: Blood glucose, lactate, pyruvate and ketone body, and carnitine levels were measured in 58 children referred with a cardiomyopathy of unknown origin. Organic acids, amino acids, oxidation of [1-14C] fatty acids to CO2 and dehydrogenation of [9,10(-3)H] fatty acids by lymphocytes were measured. Mitochondrial respiratory chain complex activity was measured in skeletal muscle and in endomyocardial biopsies. Acid a-glucosidase activity was measured in infants with hypertrophic cardio-myopathy. The prevalence of metabolic disorders was 22.4% (13/58-CL95%; 11.4-33.3%): four infants had a storage disease (Pompe's disease (3), Hurler's disease (1); two patients had a fatty acid beta-oxidation defect (systemic carnitine deficiency (1) and very-long chain acyl-CoA dehydrogenase deficiency (1)); respiratory enzyme deficiency was diagnosed in seven patients. This defect was confined to the myocardium in six. In the remaining 45 patients, metabolic screening was unrevealing. CONCLUSION: Metabolic screening should be performed in all children with cardiomyopathy as the prevalence of metabolic disorders is high in this population. This may help to define therapeutic strategy and to improve genetic counselling.

Adolescent↗
PubMed1998

Left ventricular ejection fraction in children measured by three-dimensional echocardiography using a new transthoracic integrated 3D-probe. A comparison with equilibrium radionuclide angiography.

BACKGROUND: Three-dimensional echocardiography allows calculation of left ventricular ejection fraction without geometric assumption on the ventricular shape. Our aim was to validate this technique in a paediatric population with distorted ventricles. METHODS: Twenty-one patients aged 6 months to 17 years underwent equilibrium radionuclide angiography and three-dimensional echocardiography. Fourteen patients had dilated cardiomyopathy and seven had univentricular hearts. A new, easy to handle, transthoracic rotational probe was used and motion artefacts were limited during the rotation (3 degrees intervals with ECG and respiratory gating). Left ventricular volumes and ejection fraction were calculated using the Simpson's rule with 12 slices. RESULTS: Three-dimensional echocardiography correlated well with equilibrium radionuclide angiography for ejection fraction measurement (r = 0.90; the mean difference between the two methods being 3.8 +/- 6%). Intra-observer and inter-observer variabilities for 3D echocardiography were 2.4% and 4.5%. CONCLUSIONS: Three-dimensional echocardiography is an accurate, non-invasive, and reproducible methods to measure left ventricular ejection fraction in children.

Adolescent↗
PubMed1998

Relation of genotype 22q11 deletion to phenotype of pulmonary vessels in tetralogy of Fallot and pulmonary atresia-ventricular septal defect.

OBJECTIVE: To compare the morphology of the pulmonary vessels in tetralogy of Fallot or pulmonary atresia-ventricular septal defect (PA-VSD) with (del22q) and without 22Q11 deletion (non-del22q). PATIENTS: 94 consecutive infants (54 with tetralogy of Fallot, 40 with PA-VSD) were studied using ultrasound and catheterisation. MOLECULAR INVESTIGATIONS: Identification of the 22q deletion was performed either by fluorescent in situ hybridisation or polymerisation chain reaction genotyping. RESULTS: 25 patients were del22q (16/40 (40%) PA-VSD v 9/54 (17%) tetralogy of Fallot; p < 0.02). Major aortopulmonary collateral arteries was more common in patients with PA-VSD-del22q (p < 0.03). Such collaterals were identified in 13 patients: 10 del22q and three non-del22q (p < 0.001). The size of the right and left pulmonary arteries expressed as a standard deviation (SD) difference of the normal range was -4.2 (quartiles -5.3 and -2.9) for PA-VSD del22q, and -2.6 (-3.1 and -1.8) for PA-VSD non-del22q (p = 0.02). The mean (SD) difference between the measured and theoretical Nakata index was -373 (94) for PA-VSD del22q v -245 (93) in PA-VSD non-del22q (p = 0.0002). In tetralogy of Fallot patients with and without del22q, the size of the pulmonary arteries was similar (p = 0.6). CONCLUSIONS: A "specific" phenotype could be defined in patients with deletion: PA-VSD, major aortopulmonary collateral arteries with complex loop morphology, and small central pulmonary arteries. Differences in the morphology of the pulmonary vessels may indicate a different timing of the faulty developmental pathway in patients with and without 22q11 deletion.

Aorta↗
PubMed1998

Maintaining tricuspid valve competence in double discordance: a challenge for the paediatric cardiologist.

OBJECTIVES: To establish the prevalence of tricuspid valve abnormalities in children with a double discordant heart (or congenitally corrected transposition of the great arteries); to study the influence of the loading conditions induced by various surgical interventions on the right and left ventricle in patients with double discordance and an abnormal tricuspid valve; and to propose a rational surgical approach. METHODS: Case notes were reviewed of 141 consecutive patients admitted in the first year of life with various types of double discordance (intact ventricular septum (group 1), ventricular septal defect (group 2), ventricular septal defect and pulmonary obstruction (group 3)). A study group of 62 patients with an abnormal tricuspid valve was selected by cross sectional echocardiography. These were followed up through palliative and open heart procedures with grading of tricuspid regurgitation. RESULTS: Tricuspid valve abnormalities were more common in groups 1 and 2 (60% and 56%) than in group 3 (31%). Preoperative tricuspid regurgitation was more common in group 2 (90%) than in groups 1 and 3 (38% and 36%). Ten patients in groups 1 and 2 died in the neonatal period with severe tricuspid regurgitation, associated with coarctation of the aorta in 60%. Eight patients in group 1 had no surgery and are doing well, with a competent tricuspid valve. Palliative procedures were undertaken in 28 patients: 14 had pulmonary artery banding, which resulted in a decrease in tricuspid regurgitation, 12 in group 2 by reducing the pulmonary blood flow and two in group 1 by changing the septal geometry; 14 in group 3 had an aortopulmonary shunt, which induced tricuspid regurgitation in two. Twenty patients are still alive after palliation, with stable tricuspid valve function. Repair of the tricuspid valve was unsuccessful in the three patients who underwent conventional surgery, leaving the right ventricle facing the systemic circulation. In two patients with a competent but abnormal tricuspid valve, conventional surgery induced severe tricuspid regurgitation. Of the 15 patients who underwent conventional surgery, only 10 survived (mortality 33%): eight with a tricuspid valve prosthesis and two with severe residual tricuspid regurgitation. However, tricuspid regurgitation decreased after anatomical correction (nine patients), restoring a systemic left ventricle and a subpulmonary right ventricle, even when the tricuspid valve was not repaired (five patients). Eight patients are doing well after anatomical correction (mortality 11%). CONCLUSIONS: Tricuspid valve function in double discordance with an abnormal tricuspid valve depends on the loading conditions of both ventricles and on the septal geometry. Interventions that increase right ventricular volume or decrease left ventricular pressure are likely to induce tricuspid regurgitation, while those that decrease right ventricular volume or increase left ventricular pressure are likely to improve tricuspid valve function. Repair of the tricuspid valve always failed when the right ventricle was left in a systemic position and always succeeded when the right ventricle was placed in a subpulmonary position. These results should be taken in to account when dealing with patients with double discordance and an abnormal tricuspid valve.

Female↗
PubMed1998

[A pulmonary vascularization study in pulmonary atresia with an interventricular defect in relation to the presence of a chromosome 22 deletion].

A normal lung is supplied by a pulmonary artery branching from the pulmonary trunk. Major aorto-pulmonary collateral arteries (MAPCAs) are found in combination with various congenital heart malformations such as pulmonary atresia with ventricular septal defect (PA-VSD). Now that MAPCAs are used for unifocalization in patients with PA-VSD, the question arises as to whether the morphologic criteria of these collateral arteries could help to provide better results. We compared the morphology of the pulmonary vascular bed, the origin, course and connections of the MAPCAs in 40 consecutive infants with PA-VSD with or without 22q deletion (del22q11.2.). All underwent echocardiographic evaluation and catheterization. Identification of del22q11.2. was performed by FISH study. Del22q11.2. was identified in 16 pts (40%); the presence of MAPCAs was significantly higher in patients with del22q11.2. (9/16 vs 3/24, p = 0.01). While complex morphology of MAPCAs, anastomoses with the central pulmonary artery outside the lung and absent ductus arteriosus were associated with del22q11.2, confluence of the pulmonary arteries was not a relevant phenotypic difference. The size of the right and left pulmonary arteries expressed as a standard deviation difference of the normal range for body surface area was -4.2 (quartiles -3.1/-1.8) for PA-VSD with del22q11.2. and -2.6 (quartiles -5.3/-2.9) for PA-VSD without del22q11.2. (p = 0.02). The difference between measured and theoretical Nakata index was -373 +/- 94 for PA-VSD with del22q11.2. vs. -245 +/- 93 for PA-VSD without del22q11.2. (p = 0.0002). A specific pulmonary vascular bed phenotype could be defined in patients with PA-VSD with del22q11.2. deletion: MAPCAs with complex loop morphology and small but confluent central pulmonary arteries. These findings indicate a different timing of the faulty development pathway of the pulmonary vascular bed in patients with and without del22q11.2. This phenotype difference may help our understanding of maldevelopment and facilitate decisions concerning the suitability of these arteries for unifocalization procedures.

Angiography↗