Search PubMed⌕ Search

Biomedical subjects

D Sidi

Publications and source records attributed to D Sidi.

At least 145 records · Page 8Linked to original sources
PubMed1995

[Percutaneous occlusion of patent ductus arteriosus by the Rashkind double-umbrella device].

BACKGROUND: The transcatheter option consisting of implanting and releasing an occlusive device designed as a double-umbrella is an interesting alternative to surgery aimed to close persistently patent ductus arteriosus. POPULATION AND METHODS: Closure of a duct with the Rashkind device had been planned in 113 children. The procedure was abandoned in 12 with inadequately sized ducts (too large or too small). This study therefore included 101 attempts in patients aged 2.3 months to 18.5 years (m +/- 1 SD = 45.9 +/- 43.2 months) whose weights ranged from 3.3 to 87 kg (m +/- 1 SD = 15.7 +/- 11.7 kg). The narrowest dimension of the duct on the aortograms ranged from 1.2 to 6.2 mm (m +/- 1 SD = 2.9 +/- 0.9 mm). RESULTS: The procedure failed in seven patients because of a too large and/or tubular vessel, causing removal of the device prior to release in five patients, or surgical extraction after it had embolized into a pulmonary artery branch in two patients. An early acute hemolysis requiring again the surgical removal of an instable device in a tubular duct was seen in one case. Two patients had femoral artery occlusion successfully treated with thrombolytic agents. Complete occlusion was immediately proven in 32 (35%) of the 92 successful and stable implantations. These figures raised to 64% (59 cases) prior to discharge. At final follow-up (0.3-59 months, m +/- 1 SD = 13.8 +/- 14.4 months), another 16 total occlusions were observed and one patient was successfully managed by a second implantation. The final occlusion rate was 83% (76 cases). Of the 16 residual shunts, five were surgically suppressed and the remaining were minimal. CONCLUSION: Transcatheter occlusion of the patent ductus arteriosus is safe in children weighing more than 5 kg, having ducts with a narrowing ranging from 1 to 6 mm. It is efficient in five out of six cases and has less disadvantages than surgery.

Adolescent↗
PubMed1995

[Pulmonary atresia with ventricular septal defect: therapeutic strategy in newborn infants].

Pulmonary atresias with ventricular septal defect, a right ventricular infundibulum and pulmonary artery separated by an imperforated membrane and a complete pulmonary tree with two branches in continuity are called "favourable" forms of this malformation. The authors studied 29 neonates, less than 1 month old, in whom the malformation was both ductus- and prostaglandin-dependent, prostaglandin infusion being essential for pulmonary flow and impossible to stop because of the resulting severe hypoxia. The choice of treatment depended on the anatomical form defined by angiocardiography. In the 19 regular forms with regular pulmonary arteries with little hypoplasia, percutaneous perforation-dilatation was successful in 3 out of 5 attempts with one secondary death and 2 good results leading to complete repair; anastomosis was performed in 9 cases with 3 deaths, 1 partial result and 5 good results which were followed by complete repair in 3 cases; primary complete repair attempted in 7 cases led to 1 death and 6 successes completed in 3 cases by reoperation for left pulmonary artery stenosis. In the 10 less favourable anatomical forms with stenosis or severe hypoplasia or the pulmonary branches, only palliative procedures were proposed: 2 perforations-dilatations which only gave partial results, 7 anastomoses with 1 death and 4 partial results; and 1 ventriculo-pulmonary connection without closure of the ventricular septal defect (good result). In view of the good results obtained over the 6 years of the study, the authors advise primary complete correction for the anatomically favourable forms of the malformation when weaning from prostaglandin infusion is impossible.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiocardiography↗
PubMed1995

[Percutaneous dilatation of recurrent coarctation of the aorta in the 1st year of life].

It is not rare for surgery of coarctation of the aorta to be complicated by recurrence of the lesion at medium-term, especially when it is performed very early in life. Advances in interventional catheterisation now offer an alternative to surgical reoperation. This study is a retrospective analysis of balloon angioplasty in 20 patients in whom isthmic stenosis had been operated before the age of one month in 19 cases, in whom recurrent coarctation was identified 3.2 +/- 2.1 months later. The percutaneous angioplasty was performed by a femoral arterial approach at an average age of 5.4 +/- 2.3 months. The femoral pulses returned together with a fall in the transisthmic systolic pressure gradient from 58.3 +/- 23.4 mmHg to 18.3 +/- 12.5 mmHg, and the isthmic lumen increased by +117 +/- 52%. Judged by the residual pressure gradient, the results were good, the best results being observed in the shortest and most severe stenoses. After a maximum follow-up of 5 years (average: 20.1 +/- 16.6 months), the angioplasty was successful in 14 cases (70%), 4 cases had a mild residual gradient (20%) and 2 were failures (10%). None of the patients required reoperation. There were no fatalities or early aneurysmal complications in the dilated zone monitored by echocardiography and magnetic resonance imaging. The only complication was femoral artery obstruction (6 cases) which was successfully thrombolysed in 5 cases but which recurred at long-term in 3 cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Coarctation↗
PubMed1995

[Therapeutic strategy in newborn infants with multivisceral failure caused by interruption or hypoplasia of the aortic arch].

Left heart obstructive lesions, in particular interrupted aortic arch or severe forms of coarctation with hypoplasia of the aortic arch, are the main cause of cardiac failure in the neonate and are often at the root of multiple organ failure which worsens the prognosis. Based on a retrospective study of 35 neonates admitted between July 1984 and June 1994, the authors attempted to identify the prognostic factors for admission to the intensive care unit and the optimal timing for operation of these patients. All neonates with a ductus-dependent aortic obstructive lesion and severe multiple (at least four) organ failure, were included in the study. There was a high mortality (54%) including firstly 7 patients who died in the three days following admission to the intensive care unit (20%); this was so-called "medical" mortality for which there was no identifiable poor prognostic factor. On the other hand, the surgical mortality (12 out of 28 cases, 43%) was significantly different in neonates operated before recovery from multiple organ failure (72%) and those operated after recovery from multiple organ failure (17%). Based on these results, the authors propose a therapeutic strategy based on prolonged preoperative intensive care until the initial multiple organ failure is reversed rather than early surgery.

Aorta, Thoracic↗
PubMed1994

Endomyocardial biopsies for early detection of mitochondrial disorders in hypertrophic cardiomyopathies.

Considering the high proportion of unexplained hypertrophic cardiomyopathies on the one hand and the occurrence of cardiomyopathies in several mitochondrial disorders on the other, we hypothesized that isolated hypertrophic cardiomyopathies in infancy could occasionally be the result of defects of oxidative phosphorylation. By means of a scaled-down technique, we were able to investigate oxidative phosphorylation on minute amounts of endomyocardial tissue (1 mg) in three patients with concentric hypertrophic cardiomyopathy (shortening fraction in diameter, 18% to 27%; normal mean +/- 1 SD, 33 +/- 3%) and in control subjects. Although the absolute respiratory chain enzyme activities in the endomyocardial biopsy specimens of the patients were within the low normal range, the determination of the activity ratios allowed us to ascribe hypertrophic cardiomyopathies to respiratory chain enzyme abnormalities in all three cases (complex I, two cases; multiple enzyme deficiency, one case). The respiratory chain enzyme activity ratios, which are normally constant irrespective of the tissue tested, were markedly abnormal in all three patients (cytochrome c oxidase/reduced nicotinamide-adenine dinucleotide cytochrome c reductase, 4.6 to 10.4; normal mean +/- 1 SD, 2.9 +/- 0.5). We conclude that mitochondrial disorders should be regarded as potential causes of hypertrophic cardiomyopathy in early infancy. Because cardiac catheterization is routinely performed for hemodynamic investigation of cardiomyopathies, we suggest that endomyocardial biopsies be considered as a tool for early detection of mitochondrial cardiomyopathies, especially in hypertrophic forms of the disease.

Biopsy↗
PubMed1994

A gene for Holt-Oram syndrome maps to the distal long arm of chromosome 12.

Holt-Oram syndrome (HOS) is an autosomal dominant condition of unknown origin characterized by congenital septal heart defects with associated malformations of the upper limbs (radial ray). Here, we report on the mapping of a gene causing HOS to the distal long arm of chromosome 12 (12q21-qter) by linkage analysis in nine informative families (Zmax = 6.81 at theta = 0 at the D12S354 locus). Also, multipoint linkage analysis places the HOS gene within the genetic interval between D12S84 and D12S79 (multipoint lod-score in log base 10 = 8.10). The mapping of a gene for HOS is, to our knowledge, the first chromosomal localization of a gene responsible for congenital septal heart defect in human. The characterization of the HOS gene will hopefully shed light on the molecular mechanisms that govern heart septation in the early stages of embryogenesis.

Abnormalities, Multiple↗
PubMed1994

[Palliative treatment of tetralogy of Fallot by percutaneous dilatation of the right ventricular outflow tract. 40 cases].

This study was undertaken to assess the value of percutaneous dilatation of the right ventricular outflow tract as a substitute for surgical systemic pulmonary anastomosis in varieties of tetralogy of Fallot with severe irregularity or major pulmonary arterial hypoplasia unsuitable for complete repair of first intention. Fifteen neonates aged 3 to 23 days with severe desaturation (SaO2 = 73 +/- 11%) and twenty five children aged 1.2 to 174 months with anoxic crises or severe desaturation (SaO2 = 67 +/- 15%) fulfilled these criteria. They underwent right heart catheterisation completed by an attempted pulmonary dilatation. This manoeuvre failed in 6 cases, all neonates, because it was not possible to cross the annulus or maintain the balloon in position, or because of infundibular perforation. There were complications in 5 cases, all neonates: 2 tamponades with 1 death, one dissecting aneurysms of the annulus, 1 gastroenteritis and 1 caval thrombosis. Of the 34 patients dilated, 8 were poor results, mainly in the older age group (7 cases) and 26 were successful as judged by a significant improvement in arterial saturation. However, 7 patients rapidly deteriorated due to anoxic crises (6 infants and children) or fatal secondary tamponade (1 neonate). Therefore, there remained 19 stable successful procedures, 49% of attempts, representing 56% of successful attempts and 73% of primary successes. In neonates, these proportions were respectively: 47%, 78% and 87%, and in the older children: 48%, 48% and 63%.(ABSTRACT TRUNCATED AT 250 WORDS)

Balloon Occlusion↗
PubMed1994

[Risk factors of coronary graft disease following heart transplantation in children].

Coronary disease after cardiac transplantation is a major medium and long-term complication in adult patients. In childhood, this is reputed to be rare and, therefore, the authors undertook a study to evaluate its incidence and the role of potential risk factors in this age group. The study included 30 children followed up at least one year after cardiac transplantation and investigated by at least one selective coronary angiography after the first postoperative year. Seventeen patients (57%) had a normal coronary angiography but 13 had coronary lesions (43%). The two groups were compared for age, sex, HLA groups of the donor-recipient couple, the duration of ischaemia of the transplants, cytomegalovirus serology, lipid profile, number of episodes of acute rejection that were treated, the necessity for steroid therapy for more than 3 months, and the blood pressure. The only significant differences, probably inter-related, were the number of rejections treated, greater in the group with coronary lesions (2.23 +/- 1.01 per patient) than in the group with normal coronary arteries (1.53 +/- 1.01 per patient) (p < 0.05) and the necessity of triple therapy with addition of prednisone, greater in the first group (9/13) than in the second (4/17) (p < 0.02). These results show that coronary disease after cardiac transplantation is as common and as early in children as in adults. They strongly suggest an important role of immunological factors. On the other hand, the authors' experience did not confirm the role of other potential risk factors.

Adolescent↗
PubMed1993

Investigation of respiratory chain activity in human heart.

Although disorders of oxidative phosphorylation have long been regarded as neuromuscular diseases only, they can actually give rise to any symptom specifically affecting any organ or tissue, particularly in childhood. The early diagnosis of such a condition may thus require the specific assessment of the mitochondrial function in the organ or tissue shown to be clinically involved. A method is presented allowing such an early detection of respiratory chain defects in human heart. Respiratory chain enzyme studies were carried out using endomyocardial biopsies, less than 2 mg fresh weight. Enzyme activities measured in the endomyocardial biopsies were compared with those obtained using other sampling methods (surgical and postmortem microsamples). A comparison of the respiratory chain enzyme activities in heart and other human tissues is also presented. It was found that (i) the activities of respiratory chain complexes in human heart were similar with any sampling method; (ii) these activities were high compared to other human tissues, allowing the use of heart microsamples for enzyme measurements; (iii) the activity ratios between complexes of the respiratory chain were similar in heart and other human tissues or cells as well, allowing us to confidently characterize potential mitochondrial defects and to compare their expression in different tissues or cells. The value of such investigations on endomyocardial biopsies is illustrated in the case of two patients affected with mitochondrial cardiomyopathy and is discussed in regard to the tissue-specific nature of mitochondrial diseases.

Adolescent↗
PubMed1993

Routine diagnosis of DiGeorge syndrome by fluorescent in situ hybridization.

In a series of ten patients affected by DiGeorge syndrome, we screened, by high resolution banding and fluorescent in situ hybridization of a cosmid probe, for microdeletions associated with this syndrome. In the ten patients, a microdeletion was demonstrated by in situ hybridization, but suspected only in two patients by high resolution banding.

Adult↗
PubMed1993

Aortic arch thrombosis in the neonate.

Two cases of neonatal aortic arch thrombosis are reported. One patient, who had ascending aortic thrombosis, died preoperatively. The other had reoperation and is alive and well at 6 months' follow-up. No obvious cause was found.

Adult↗
PubMed1993

Pediatric cardiac transplantation for congenital heart defects: surgical considerations and results.

Among 54 children who underwent 55 heart transplantations, 24 (44%) (mean age, 4.9 +/- 4.8 years; range, 9 days to 18 years) had congenital defects with the following diagnoses: single-ventricle variants (6), hypoplastic left heart syndrome variants (5), transposition complex (6), and miscellaneous defects (7). Twenty patients (83%) had undergone 43 prior operations. Additional surgical procedures included repositioning of transposed great arteries (11), reconstruction of the aortic pathway (4), reconstruction of the pulmonary pathway (8), correction of situs inversus (1), and correction of anomalous pulmonary (1) or systemic (1) venous drainage. Reconstructive procedures were performed using donor or recipient tissue or both. There were six early deaths (hyperacute rejection, 1 patient; pulmonary hypertension, 1; graft failure, 2 patients; infection, 2) and six late deaths (sudden death, 2; chronic rejection, 2; nonspecific graft dysfunction, 1; lymphoproliferative disease, 1). The survival rate was 43% +/- 12% at 3 years. No deaths were related to surgical technique. Survival was not significantly different in pediatric recipients with cardiomyopathy (67% +/- 9%; p = 0.22). Accelerated coronary artery disease was noted in 4 operative survivors (22%; 70% confidence limits, 12% to 36%). All late survivors were free from cardiac symptoms after a mean follow-up of 34 +/- 24 months (range, 6 to 71 months). Based on this study, we reached three conclusions. (1) Careful planning of both harvesting and transplantation procedures allows heart transplantation in recipients with congenital heart diseases. (2) The surgical technique may be demanding, but the early risk is not increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

High-frequency ventilation in newborn lambs after intra-uterine creation of diaphragmatic hernia.

Infants with congenital diaphragmatic hernia (CDH) die, because their lungs are hypoplastic and their pulmonary vascular resistance remains elevated after birth. In human newborns, it is difficult to appreciate the benefit of new therapeutic approaches, because the pathological findings are not uniform, the disease is rare and the clinical criteria for poor prognosis with conventional therapy are uncertain. To study the benefit of high-frequency ventilation (HFV) the use of Tolazoline in CDH, we created a diaphragmatic defect in sheep fetuses at 0.6 gestation and studied full-term newborns after a caesarian section. A sternotomy was performed to place catheters and flow probes on the aorta and pulmonary artery and to clamp the ductus arteriosus and the left pulmonary artery. Twins were used as control, and the CDH lambs were either ventilated with conventional ventilation (CV) or HFV. 23 ewes were operated upon with a 22% abortion rate and 31 newborn lambs (10 controls and 21 CDH) were studied. A complete gasometric and hemodynamic study was performed in 23 lambs (7 controls, 8 CDH with CV and 8 CDH with HFV). Clinical and pathological findings of the lambs with CDH were very similar to severe CDH in humans with bilateral lung hypoplasia, severe respiratory distress, high pulmonary vascular resistance and severe hypoxemia. HFV dramatically improved CO2 elimination, allowed less aggressive ventilation, and was associated with higher flows and lower systemic and pulmonary vascular resistance. However, HFV did not improve oxygenation leaving the newborn with severe hypoxemia associated with massive intrapulmonary foramen ovale shunting from right to left.

Animals↗
PubMed1993

[Neonatal cardiac failure secondary to hypocalcemia caused by maternal vitamin D deficiency].

BACKGROUND: Heart failure is a rare manifestation of neonatal hypocalcemia. This paper describes such a case resulting from maternal vitamin D deficiency. CASE REPORT: A full-term boy, born in December after a normal pregnancy, was admitted at the age of 6 weeks because of dyspnea that appeared during suckling. Examination showed heart failure. Electrocardiogram showed that the corrected QT-interval was lengthened (0.54 s, normal < 0.45 s). Echocardiogram showed dilated, hypokinetic myocardiopathy. His serum calcium concentration was low (1.40 mmol/l) and phosphate was high (2.8 mmol/l); his alkaline phosphatase was 513 Ul/l. His blood PTH concentration was high (120 pg/ml) and his 25 (OH) D was low (5 ng/ml). The patient was given calcium (1 g/m2/day) and 1.25 (OH)2 D (2 micrograms/day orally). His serum calcium returned to normal within 4 days, and his cardiac abnormality was resolved within 3 months. His mother's blood 25 (OH) D concentration was very low (3 ng/ml), 6 weeks after birth. CONCLUSION: Neonatal hypocalcemia appears to have been compounded in this case by a maternal vitamin D deficiency. Hence, all pregnant women at risk of deficiency should be given vitamin D.

Calcium↗
PubMed1993

[Perforation-dilatation of pulmonary atresia with intact interventricular septum in neonates and infants].

Sixteen children (14 neonates less than 1 week old and 2 infants aged 3 and 6 months) had a "favorable" type of pulmonary atresia with an intact interventricular septum in which the hypoplasia of the right ventricle was mild and the cavity tripartite with a well developed infundibulum arriving in contact with a good-sized pulmonary artery from which it was separated by a totally or almost totally imperforate dome. They underwent a procedure associating an infusion of prostaglandin. E1 and an attempted pulmonary valve disobliteration by interventional catheterisation: needle puncture followed by balloon dilatation. There were 4 failed procedures (impossible puncture or dilatation), only one of which in the last 10 cases. The outcome of the 12 primary successes was related to the rapidity of recovery of right ventricular diastolic function: 7 patients were cured within a few days or weeks with prostaglandin therapy: 5 children required surgical anastomosis with a longer recovery period--3 cures but 2 deaths. Overall, there were two myocardial effractions without serious complications and 1 enterocolitis which was long-lasting but eventually cured. Two mild residual stenoses were redilated. In conclusion, the puncture-dilatation technique may be used instead of surgical valvectomy in favorable forms of pulmonary atresia with intact septum in the neonate. With experience, it was possible to remove the obstruction in 9 out of 10 cases with a minimum of complications. It is the compulsory first stage to complete cure, the probability and rapidity of which depend on recovery of right ventricular compliance.

Angiocardiography↗
PubMed1993

[Cavopulmonary shunts in the treatment of univentricular heart diseases in children. An experience of 60 cases].

Sixty children with a complex cardiac malformation consisting of a single functional ventricle and a protected pulmonary circulation, previously palliated by one or several Blalock anastomoses (40 cases) underwent a cavopulmonary shunt procedure. All but one had an excellent hemodynamic status: ventricular end diastolic pressure < 15 mmHg, mean pulmonary pressure < 20 mmHg, pulmonary vascular resistance < 3 units and a Mayo Clinic index (a combination of these parameters and pulmonary and systemic blood flow) < 4. The shunt was complete from the outset in the 27 most favorable cases which did not require any other surgical procedure. There were 2 immediate failures which necessitated reducing the reconstruction to a partial shunt; 9 cases were complicated by thrombosis of the intercaval connection (2 case, 1 death), by neurological complications (2 cases, 1 death), by chronic serous effusions (5 cases): of the 21 survivors followed up for a maximum of 54 months (average 28 +/- 9 months), 18 were well and 2 handicapped by venous stasis. The shunt was partial in 33 cases, especially in 17 cases because it was necessary to operate the pulmonary branches, the subaortic area, or an atrioventricular valve; there was no immediate mortality but 5 complications which were related to an associated procedure in 3 cases. There were no complications in 28 cases: of the 30 children followed up an average of 24 months, there were 3 secondary degradations (2 deaths and 1 cardiac transplantation), 10 shunts completed 2 to 32 months later with no deaths and 8 excellent results, and 17 children waiting for more favorable conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗