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D Sidi

Publications and source records attributed to D Sidi.

At least 73 records · Page 4Linked to original sources
PubMed2001

[Interest in myocardial scintigraphy following the arterial switch procedure for transposition of the great vessels].

Coronary artery obstruction is the main late complication of the so-called arterial switch operation designed to repair transpositions of the great arteries in newborn infants by switching the great vessels and transferring the coronary ostia onto the posterior vessel. Our aim was to study the links between myocardial perfusion and coronary artery anatomy after the arterial switch operation. Forty-five patients (5.863 years) underwent a 201Tl myocardial SPECT and a selective coronary artery angiography. The latter was normal in 20 children: 13 had also a normal myocardial scan but 7 had myocardial perfusion defects including 2 with angina who had a very low coronary reserve at positron emission tomography. Twenty-five patients had severe coronary artery lesions: 5 with a normal myocardial scan and 20 with perfusion defects. Twelve out of these 20 underwent surgical revascularization and the SPECT images went back to normal in all within 6 months after surgery. Specificity and sensitivity of myocardial SPECT in detecting coronary artery lesions were 78% and 69% whereas positive and negative predictive values were 74 and 73%. We conclude that myocardial SPECT imaging is not the right way to detect late post arterial switch coronary artery lesions. It is helpful in decision making as to submit these children to surgical revascularization and in assessing its postoperative effectiveness.

Adolescent↗
PubMed2001

[Quality of life of adults with univentricular hearts].

This study sought to evaluate the quality of life of surviving adults with univentricular heart and to determine the impact of sociodemographic and clinical characteristics on quality of life. The health records of 89 survivors with univentricular heart living in France at the time of the study were reviewed. They were 17 to 49 years old (median: 21). Sixty-seven patients answered the Duke questionnaire. Sociodemographic and clinical variables were similar in the responders and non-responders. The scores of patients who answered the questionnaire were compared with national norms. The impact of sociodemographic and clinical variables on individual Duke's measures was assessed. The Duke scores of adults with univentricular heart were similar to those of the normal population. Cyanosis predicted a worse score for physical (p = .05) and perceived health measures (p = .02). The higher educational level predicted a better score for physical (p .004), mental (p = .01), and general health measures (p = .02). Orthopaedic problems worsened social score (p = .05). Psychosocial problems worsened pain score (p = .04). Mitral atresia, in comparison with the other anatomical types, worsened perceived health score (p = .02). Finally, patients younger than 23 years scored better for almost all of health and dysfunction measures. In conclusion, despite repeated interventions and other disease-related everyday stresses, a selected group of adults with univentricular heart had a satisfying quality of life. These patients probably developed copying mechanisms, easing the psychological stress, and oriented themselves towards a different set of values in everyday life so that to accept disabilities and to recalibrate personal expectations.

Adolescent↗
PubMed2001

[Arterial dysfunction after treatment of coarctation of the aorta].

The long term follow-up after successful coarctation repair has a late cardiovascular morbidity, includes systemic hypertension at rest or/and after exercise. The pathophysiology mechanisms responsible have not been well determined. We studied 70 normotensive subjects at rest (age, 14 +/- 5 y; pressure, 116 +/- 13/56 +/- 9 mmHg), who had an isolated coarctation with a good repair defined by the absence of gradient between upper and lower right limb (0.-26 mmHg). After exercise testing we defined two groups: Coa HT: Hypertension at exercise equal or over 200 mmHg, n = 20 (228 +/- 23 mmHg) and Coa HT: Normotensive at exercise = 10 (163 +/- 24 mmHg). These subjects were mached sex-age and blood pressure to 70 controls (age, 13 +/- 3 y; pressure, 115 +/- 10/56 +/- 6 mmHg). Using a high-resolution echographic technique, we assessed the systolic, diastolic diameter and the intima media thickness (IMT) of the common carotid artery (CCA) to define mechanical indexes: Cross sectional compliance (CSC), distensibility (CSD) and incremental elastic modulus (Einc) in each group. CCA pressure waveform and the local pulse pressure were determined in 32 subjects to define augmentation index (AI). The changes of the brachial artery diameter in response to reactive hyperaemia (flow mediated dilation: FDM) and to glyceryltrinitrate (GTNMD) were measured. The IMT was significantly increased in the Coa group (by 8%, p < 0.001) and higher in the Coa HT group compared with the Coa NT group (0.57 +/- 0.04 mm vs 0.54 +/- 0.05 mm, p < 0.05). The CSD was lower and the Einc was higher in both groups. The carotid pulse pressure amplitude was significantly higher in the Coa HT Group (41 +/- 14 vs 33 +/- 7 mmHg; p < 0.05). The AI was higher in both Coa repair groups. Both flow-mediated dilation (FMD) and GTN-mediated dilation (GTNMD) of the brachial artery were lower in the Coa group (respectively 5 +/- 3 vs 7 +/- 3%; p < 0.01; 16 +/- 8 vs 23 +/- 9%; p < 0.01). GTNMD was inversely correlated with maximum systolic blood pressure on exercise (r = 0.31, p = 0.03). The IMT of the CCA was related to the local pulse pressure in both groups of coarctation repair. The combination of distensibility decrease in the proximal arterial bed with an impairment of distal artery reactivity would account for the elevation of exercise blood pressure in subjects who had coarctation repair. The increase of local pulse pressure influences the carotid wall hypertrophy.

Adolescent↗
PubMed2000

Percutaneous replacement of pulmonary valve in a right-ventricle to pulmonary-artery prosthetic conduit with valve dysfunction.

BACKGROUND: Valved conduits from the right ventricle to the pulmonary artery are frequently used in paediatric cardiac surgery. However, stenosis and insufficiency of the conduit usually occur in the follow-up and lead to reoperations. Conduit stenting can delay surgical replacement, but it aggravates pulmonary insufficiency. We developed an innovative system for percutaneous stent implantation combined with valve replacement. METHODS: A 12-year-old boy with stenosis and insufficiency of a prosthetic conduit from the right ventricle to the pulmonary artery underwent percutaneous implantation of a bovine jugular valve in the conduit. FINDINGS: Angiography, haemodynamic assessment, and echocardiography after the procedure showed no insufficiency of the implanted valve, and partial relief of the conduit stenosis. There were no complications after 1 month of follow-up, and the patient is presently in good physical condition. INTERPRETATION: We have shown that percutaneous valve replacement in the pulmonary position is possible. With further technical improvements, this new technique might also be used for valve replacement in other cardiac and non-cardiac positions.

Angiography↗
PubMed2000

Transcatheter implantation of a bovine valve in pulmonary position: a lamb study.

BACKGROUND: Pulmonary regurgitation can lead to severe right ventricular dysfunction, which is a delicate postoperative problem in the long-term follow-up of patients who had surgery for congenital heart diseases. Clinical conditions of patients suffering from pulmonary valve incompetence are improved by valve replacement with a prosthetic valve. To date, the surgical approach is the only option to replace a pulmonary valve. We report the first experience of percutaneous pulmonary valve implantation. METHODS AND RESULTS: A fresh bovine jugular vein containing a native valve was sutured into a vascular stent and then cross-linked with a 0.6% glutaraldehyde solution for 36 hours. After being hand-crimped onto a balloon catheter, the device was inserted percutaneously according to standard stent-placing techniques. The valved stent was finally deployed in the position of the native pulmonary valve of the lamb. Hemodynamic evaluation was carried out before and 2 months after implantation. Anatomic evaluation was finally performed. Percutaneous pulmonary valve replacement was successful in 5 lambs. No complications were noted. Early and late angiographic and hemodynamic studies confirmed a good position of the stents with a competent valve at the end of the protocol. One stent was slightly stenotic, with macroscopically visible calcifications. CONCLUSIONS: Nonsurgical implantation of pulmonary valves is possible in the lamb. This new technique is similar to standard stent implantation. Thus, it should be feasible in humans, in whom it will lead to a significant reduction of reoperations in patients in need of pulmonary valve replacement.

Angiography↗
PubMed2000

New insight into left ventricular function in tricuspid atresia after total cavopulmonary connection: a three-dimensional echocardiographic study.

BACKGROUND: In patients with tricuspid atresia palliated by construction of a total cavopulmonary connection, both pulmonary and systemic circulations depend on the performance of the dominant left ventricle. When estimating the volume of such ventricles using cross-sectional echocardiography, it is necessary to make assumptions concerning the geometry of the ventricular shape. This is avoided by three-dimensional echocardiography, which provides direct volumetric data. Our purpose was to apply this new method to quantify left ventricular volumes and function in patients with tricuspid atresia after construction of a total cavopulmonary connection. METHODS: We studied ten patients (median age: 8 years) with tricuspid atresia who had undergone a total cavopulmonary connection, comparing them with 10 normal children matched for age, sex and size. The three-dimensional echocardiography was performed with electrocardiographic and respiratory gating. A new transthoracic integrated probe designed for small children was used with a rotational scanning increment of 3 degrees. The 60 slices obtained from the ventricular cavity were stored and formatted in a commercial system (TomTec). End-diastolic and end-systolic volumes, stroke volume and ejection fraction were calculated after manual tracing of the endocardial surfaces. The volumes were indexed to the body surface area. RESULTS: As seen in the reconstructions, the dominant left ventricle in tricuspid atresia had a spherical shape, whereas the normal left ventricle is oblong. The left ventricular volumes and function in tricuspid atresia were 54+/-4 ml/m2 (end-diastolic volume), 28+/-3 ml/m2 (end-systolic volume), 26+/-7 ml/m2 (stroke volume) and 48+/-6% (ejection fraction). These volumes were not different from those obtained in the controls (p = NS). The left ventricular stroke volume and ejection fraction in 10 patients with tricuspid atresia were lower than those calculated for the controls (p < 0.05). CONCLUSIONS: Three-dimensional echocardiography provides a quantitative insight into the pathophysiologic function of the dominant left ventricle in tricuspid atresia after construction of a total cavopulmonary connection.

Adolescent↗
PubMed2000

Influence of atrial septal defect anatomy in patient selection and assessment of closure with the Cardioseal device; a three-dimensional transoesophageal echocardiographic reconstruction.

BACKGROUND: The maximal diameter of the defect and the dimensions of the septal rims are essential parameters for the selection of optimal cases for device closure. Neither two-dimensional echocardiography nor balloon catheter sizing provide optimal data. Unique three-dimensional echocardiography might help to improve patient selection and assessment of results. Our aim was to optimize transcatheter closure of secundum type atrial septal defects using three-dimensional echocardiography. METHODS: Sixteen patients enrolled in a protocol for atrial septal defect transcatheter closure with the Cardioseal device underwent transoesophageal two- and three-dimensional echocardiography. Maximal diameter and tissue rim of the atrial septal defect were measured and compared by both methods. In the 12 patients selected for closure, the balloon stretched diameter was compared to three-dimensional echocardiography measurements. Device placement was assessed by two- and three-dimensional echocardiography. RESULTS: The shape of the atrial septal defect appeared variable on three-dimensional views: round in nine patients but complex (oval, raquet-shaped, multiple) in seven patients. The surface area of the atrial septal defect varied by 68+/-15% during the cardiac cycle. The correlation between atrial septal defect maximal diameters measured by two-dimensional transoesophageal echocardiography and three-dimensional echocardiography was better in round defects (y=1 x +1.6, r=0.99) than in complex defects (y=0.7 x -0.5, r=0.88). The antero-superior rim could only be properly assessed by three-dimensional echocardiography. In 12 patients the correlation between stretched diameter and three-dimensional echocardiography maximal diameter was poor (y=0.3 x +13, r=0.41). After placement of the device, three-dimensional echocardiography enabled the mechanism of residual shunting to be understood in three patients. CONCLUSIONS: Dynamic three-dimensional echocardiography enhances the understanding of the anatomy and physiology of atrial septal defect and should be an important process in future initiatives for device closures.

Adolescent↗
PubMed2000

Mechanical properties of the common carotid artery in Williams syndrome.

OBJECTIVE: To determine whether arterial wall hypertrophy in elastic arteries was associated with alteration in their mechanical properties in young patients with Williams syndrome. METHODS: Arterial pressure and intima-media thickness, cross sectional compliance, distensibility, circumferential wall stress, and incremental elastic modulus of the common carotid artery were measured non-invasively in 21 Williams patients (mean (SD) age 8.5 (4) years) and 21 children of similar age. RESULTS: Systolic and diastolic blood pressures were higher in Williams patients (125/66 v 113/60 mm Hg, p < 0.05). The mean (SD) intima-media thickness was increased in Williams patients, at 0.6 (0.07) v 0.5 (0.03) mm (p < 0. 001). Normotensive Williams patients had a lower circumferential wall stress (2.1 (0.5) v 3.0 (0.7) mm Hg, p < 0.01), a higher distensibility (1.1 (0.3) v 0.8 (0.3) mm Hg(-1).10(-2), p < 0.01), similar cross sectional compliance (0.14 (0.04) v 0.15 (0.05) mm(2). mm Hg(-1), p > 0.05), and lower incremental elastic modulus (7.4 (2. 0) v 14.0 (5.0) mm Hg.10(2); p < 0.001). CONCLUSIONS: The compliance of the large elastic arteries is not modified in Williams syndrome, even though increased intima-media thickness and lower arterial stiffness are consistent features. Therefore systemic hypertension cannot be attributed to impaired compliance of the arterial tree in this condition.

Adolescent↗
PubMed2000

Arterial mechanical changes in children with familial hypercholesterolemia.

Atherosclerosis is preceded by a phase of changes in the arterial wall that could have functional consequences even before the appearance of atheromatous changes. We hypothesized that early alterations of the mechanical properties of the arterial wall could precede clinical and echographic modifications. We used an automatic, computerized, ultrasonic procedure to evaluate geometric and mechanical characteristics of the common carotid artery (CCA) in normotensive children with primary familial class IIA hypercholesterolemia (FH; n=30; mean+/-SD age, 11+/-2 years old; mean+/-SD systolic/diastolic blood pressure, 109+/-9/55+/-7 mm Hg). These subjects were compared with age-matched, nonobese control subjects (n=27; 11+/-3 years old; 112+/-10/55+/-7 mm Hg). Noninvasive ultrasonic measurements were performed by the same investigator to measure the CCA luminal systolic and diastolic diameters and intima-media thickness (IMT). The cross-sectional compliance, cross-sectional distensibility, and the incremental elastic modulus of the CCA wall were then calculated. Finally, we assessed the degree of reactive hyperemia in the brachial artery produced after distal cuff occlusion and release. The changes in brachial arterial diameter in response to reactive hyperemia (endothelium-dependent dilation) and to glyceryltrinitrate (endothelium-independent dilation) were then measured. In patients with FH, we observed a significant reduction of systodiastolic variations in diameter (by 20%, P:<0.001) without a significant difference in IMT. Cross-sectional compliance and cross-sectional distensibility were significantly reduced in FH subjects (by 15%, P:<0.05 and 19%, P:<0.01, respectively). In parallel, the incremental elastic modulus was significantly increased (by 27%, P:<0.01) in children with FH. No correlation was evident between the carotid incremental modulus and either IMT or plasma low density lipoprotein cholesterol level. There was no difference in diameter of the brachial artery at rest in control and FH subjects (3.0+/-0.5 versus 3.0+/-0.4 mm). The reactive hyperemia and glyceryltrinitrate dilation were also similar in the 2 groups. However, the flow-mediated dilation of the brachial artery was smaller in the FH subjects (4.2+/-2.9%) than in controls (9.0+/-3.1%, P:<0.001). In FH, endothelium-dependent dilation was negatively correlated with the plasma low density lipoprotein cholesterol level (P:<0.04). These results indicate that increased stiffness of the CCA wall in children with FH is independent of blood pressure and could be related to endothelial dysfunction. Thus, alterations in CCA wall mechanics could be early and easily measurable markers of atheromatous changes in the arterial wall.

Biomechanical Phenomena↗
PubMed2000

Impairment of cardiac neuronal function in childhood dilated cardiomyopathy: an 123I-MIBG scintigraphic study.

UNLABELLED: Abnormalities of norepinephrine uptake have been found to reflect impairment of cardiac adrenergic neuronal function in adults with heart failure. To our knowledge, no data on childhood dilated cardiomyopathy (DCM) are available. The aim of this study was to assess the cardiac neuronal function using 123I-metaiodobenzylguanidine (MIBG) scintigraphy in children with idiopathic DCM. METHODS: We studied 26 patients (mean age, 44+/-50 mo) with DCM and left ventricular dysfunction and 12 control subjects (mean age, 49+/-65 mo) with normal left ventricular function. All subjects underwent planar cardiac imaging after intravenous injection of 20-75 MBq 123I-MIBG. A static anterior view was acquired 4 h after injection. The heart-to-mediastinum count ratio was measured as described previously. RESULTS: On the basis of a reduction of the heart-to-mediastinum count ratio, cardiac neuronal uptake of 123I-MIBG was significantly decreased in patients with DCM compared with cardiac uptake in control subjects (172%+/-34% versus 277%+/-14%; P<0.0001). A significant correlation was found between left ventricular ejection fraction and 123I-MIBG cardiac uptake in patients with DCM (y = 2.5x + 113.3; r = 0.80; P<0.0001). CONCLUSION: Cardiac adrenergic neuronal function is impaired in children with idiopathic DCM. 1231-MIBG cardiac scintigraphy is a useful tool to assess cardiac neuronal function in childhood DCM.

Cardiomyopathy, Dilated↗
PubMed2000

[Facial hemangioma associated with arterial anomalies, coarctation of the aorta, and eye abnormalities: PHACES syndrome].

BACKGROUND: Hemangiomas are frequent in childhood. Their association with dysmorphic anomalies is rare. Recently, the acronym "PHACES syndrome" was proposed to emphasize the association of Posterior fossa malformations, Hemangiomas, Arterial anomalies, Coarctation of the aorta and cardiac defects, Eye abnormalities, and Sternal malformations. CASE REPORT: A female child, 3 months old, had a large facial hemangioma. The physical examination was normal otherwise. A choroidal hemangioma and a papillary abnormality, causing amblyopia, were detected. The brain magnetic resonance imaging was normal. A subglottic hemangioma was found at endoscopy. At the age of 16 months, physical examination disclosed a heart murmur and coarctation of the aorta was detected. Moreover, the cardiac angiography showed diffuse arterial lesions. Strict surveillance was decided as there were no manifestations. DISCUSSION: Different abnormalities have been described to be associated with large facial hemangiomas. Frieden has grouped these abnormalities under the acronym PHACES. She described 43 hemangiomas and found 74 p. 100 Dandy Walker malformations and other posterior fossa malformations, 41 p. 100 arterial anomalies, 26 p. 100 cardiac or aortic malformations, 23 p. 100 ophthalmologic abnormalities. There is a high risk for the hemangiomas to develop in an airway localization. The prevalence of facial hemangiomas associated with other malformations is, to our knowledge, not known. In our department, 56 children were treated with corticosteroid therapy for severe facial hemangioma. 11 p. 100 had a cerebral abnormality. There were no cases with cardiac malformation or dysmorphism. PHACES syndrome is very rare but easy to remember. Thus in patients presenting a large facial hemangioma, it is important to conduct an attentive neurological examination completed by brain imaging and an extensive cardiovascular exploration. Special attention should be given to the ophthalmologic and sternal examinations as well as the search for hemangiomas in an airway localization.

Aortic Coarctation↗
PubMed2000

[Percutaneous closure of patent ductus arteriosus with the Amplatzer duct occluder].

BACKGROUND AND METHODS: Percutaneous closure of a moderate-to-large sized patent ductus arteriosus using multiple coils or a Rashkind double-umbrella may be technically demanding and raises a significant rate of embolization and residual shunting. This is why we tried a new self-expandable device called Amplatzer Duct Occluder to close transvenously large ductuses in eighteen patients at a median age of 2.8 years (range: 0.7 to 34). They had a patent ductus arteriosus with a minimal diameter > 3 mm (mean: 5 +/- 2 mm). The device had a mean diameter of 9 +/- 2 mm and was delivered through a 6F venous sheath. Aortography was done 5 to 10 minutes after the release and follow-up evaluation was performed with color Doppler echocardiography within 24 h, 1 and 3 to 6 months after the procedure. RESULTS: Placement was successful in all but the first patient (95%). Complete closure was achieved immediately in 4/17 patients (24%) and in 13/17 (76%) 24 h later. Two patients were lost for follow-up. Complete closure was confirmed in 14 of the 15 (93%) reviewed patients at 1 and 3 months. In all patients with a ductal diameter < or = 7.5 mm the closure was complete at 1 month. Embolization occurred in one patient with a 9.7 mm duct and surgery was undertaken. A mild and transient hematuria was observed in one patient. No pulmonary artery stenosis nor aortic obstruction were observed on follow-up. CONCLUSION: The Amplatzer Duct Occluder device offers a safe and effective option to treat patients with a ductus arteriosus which minimal diameter is up to 7.5 mm.

Adolescent↗
PubMed2000

[Three-dimensional reconstruction by transesophageal echocardiography of Amplatzer and CardioSEAL prosthetic devices after percutaneous closure and atrial septal defects].

OBJECTIVE: The Amplatzer and cardioSEAL devices are currently used for percutaneous closure of atrial septal defects. The in vivo morphology of these devices is unknown and this is why we sought to describe their geometric profile by three-dimensional echocardiography. METHODS: Thirteen patients, aged 6 to 18, underwent transcatheter closure of a secundum type atrial septal defect with either the CardioSEAL (n = 8) or the Amplatzer (n = 5) device. Three-dimensional reconstructions of the defect were obtained from transoesophageal bidimensional echocardiographic views. RESULTS: In the Amplatzer group, the stretched diameter of the defect was larger than in the CardioSEAL group (22 +/- 2 vs 18 +/- 1 mm, p = 0.003), but ehocardiographic surfaces were the same (3.3 +/- 1 vs 3.6 +/- 1 cm2, p = 0.3). The surface of the CardioSEAL device was measured at 4.8 +/- 2 cm2 whereas the Amplatzer's surface was 6.8 +/- 2 cm2 (p = 0.03). The Amplatzer device had a volume of 9 +/- 1 cm3 while the CardioSeal's volume was 3.1 +/- 1 cm3 (p < 0.0001). CONCLUSIONS: The CardioSEAL device occupies a small volume but it covers less of the septal defect and this may result in a higher incidence of residual shunting. The Amplatzer device almost always occludes the septum, but it tends to bulge into the atria and may cause mechanical complications.

Adolescent↗
PubMed2000

[Prenatal diagnosis of conotruncal heart diseases. Results in 337 cases].

Prenatal diagnosis of conotroncal disease has developed by examination of the great arteries during morphological foetal ultrasonic scanning in the second term of pregnancy. This study reports the results of a series of 337 of these malformations diagnosed in the foetus over five and a half years. Their incidence with respect to all foetal cardiac malformations is 16.2%. Tetralogy of Fallot and pulmonary atresia with ventricular septal defect make up 56% of these cases, vascular malposition 16%, coarctation with or without interruption of the aortic arch 14%, truncus arteriosus 9% and agenesis of the pulmonary valves 5%. A karyotypic anomaly was found in 28 cases (8.2%) and, in the foetus with a normal standard karyotype, deletion of chromosome 22q11 was identified in 54 out of 237 cases. There was an associated polymalformative syndrome in 29 cases (8.3%). The training of obstetricians has increased the number of antenatal diagnoses of conotroncal abnormalities. Prenatal counselling should be given by a pluridisciplinary team because the association of these malformations with chromosomal abnormalities or with syndromes difficult to diagnose is common.

Cardiovascular Abnormalities↗
PubMed2000

[Pseudo-inherited form of left heart obstructive defects revealing maternal phenylketonuria].

If an adequate diet is not given to mothers with phenylketonuria, their offsprings often exhibit intra-uterine growth retardation with associated microcephaly and various malformations. Here, we report two families in whom we observed recurrent left heart malformations associated with microcephaly masquerading as a mendelian condition and revealing a maternal phenylketonuria. These observations suggest that when confronted to recurrent heart malformations with extra-cardiac defects that are not due either to an inherited chromosomal anomaly or to a well characterized mendelian disease, a maternal teratogen should be identified and more particularly maternal hyperphenylalaninemia if an intra-uterine growth retardation or a microcephaly is part of the syndrome.

Female↗
PubMed2000

[Cardiovascular impact of end-stage renal insufficiency in children undergoing hemodialysis].

Cardiac hypertrophy and arterial dysfunction have been described in end-stage renal disease (ESDR) in adults. The incremental elastic modulus (Einc), is a marker of vascular wall material stiffness and an independant predictor of cardiovascular mortality in adults with ESRD on hemodialysis. The relationship between arterial changes and the heart is unknown in the children with ESRD in the same conditions. Using a high-resolution vascular ultrasound and a computerized system of measurement (Iotec), we assessed noninvasively 10 ESRD patients (mean +/- SD, age, 11.5 +/- 4 years; blood pressure [BP], 120 +/- 10/63 +/- 4 mmHg) and 10 age-, sex-, and BP-matched controls (mean +/- SD, age, 11 +/- 4 years; BP, 114 +/- 8/58 +/- 8 mmHg). The systolic and diastolic diameter of the common carotid artery (CCA), the thickness of the wall (intima-media thickness, IMT), the cross sectional compliance (CSC), the cross sectional distensibility (CSD) and the (Einc) were determined. CSC and CSD were evaluated at the same level of pressure. The CCA pressure waveform was obtained by applanation tonometry to assess the reflected wave by the augmentation index (AI). Further the left ventricular mass index was assessed. The flow mediated dilation (FMD) (endothelium-dependent function) and the vasodilation induced by glyceryl-trinitrate (GTNMD) (GTN, an endothelium-independent dilator) were evaluated at the brachial artery site. Compared to control subjects, ESRD patients have mechanical artery dysfunction with lower CSC and CSD (0.11 +/- 0.04 vs 0.18 +/- 0.05 mm2.mmHg-1; p < 0.01; 0.43 +/- 0.10 vs 0.82 +/- 0.20 mmHg-1.10(-2); p < 0.001) and higher Einc (2.60 +/- 1.00 vs 1.40 +/- 0.30 mmHg.10(3); p < 0.001). Furthermore an earlier return of the reflected pulse wave (AI -0.24 +/- 0.08 vs -0.58 +/- 0.06; p < 0.005) is correlated to LV mass index (r = 0.55, P < 0.01) that is significantly increased (134 +/- 63 vs 69 +/- 25 g/m2; p < 0.005). These patients have an impaired FMD (4 +/- 2 vs 7 +/- 1%; p = 0.02) with a normal GTNMD. This study shows that early arterial dysfunction can occur in children with ESRD.

Adult↗
PubMed1999

Skin elastic fibers in Williams syndrome.

The elastin gene is consistently deleted in Williams syndrome and as this protein represents the major component of the elastic fibers of the dermis, we sought to investigate skin elastic fibers in Williams syndrome as a key to unraveling extracellular matrix disorganization in this condition. Both morphometric parameters analyzed by using automated image analysis and immunofluorescence labeling with monoclonal antibodies against elastin and fibrillin 1 showed a disorganized pre-elastic (oxytalan and elaunin) and mature elastic fibers in the dermis of 10 Williams syndrome patients compared with five healthy children and one patient with isolated supravalvular aortic stenosis. Skin biopsies in Williams syndrome patients provide a simple mean to elucidate extracellular matrix anomalies. Hopefully, this method could give clues to the understanding of the elastic network anomalies in this condition and even to the consequences of these latter on elasticity and resilience of other tissues such as the arterial tree.

Adolescent↗