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D Metras

Publications and source records attributed to D Metras.

At least 55 records · Page 3Linked to original sources
PubMed1995

[Lung transplantation and respiratory function tests. Functional outcome in the presence and absence of chronic rejection].

Between may 1988 and march 1993, twenty five double lung transplants were performed and five heart/lung transplants. Lung function tests (EFR) were performed on these patients for a period of 19.2 +/- 3.4 months. The aim of this study was two-fold. First, to report our overall results and to estimate the role of the single breath nitrogen washout test (N2 slope) in the early detection of chronic rejection (RC). Secondly, to assess the diagnostic value of EFR in the discrimination of acute rejection (RA) and of cytomegalovirus pneumonitis (PCMV). There were 41 episodes of RA and 21 episodes of PCMV and they were analysed as a function of the presence or absence of RC. In the absence of RC, RA produced no change in EFR and PCMV was accompanied by a pure restrictive ventilatory defect. On the otherhand, RA and PCMV lead to a worsening of obstruction and an hypoxaemia which characterises RC. The diagnosis of RC was made, on average, 14.4 +/- 2.9 months after surgery. However, from the sixth month the nitrogen slope was significantly increased and other parameters of EFR (particular maximal flows at low lung volume) remained normal. Thus, our results suggest that the N2 slope, measured in the absence of any evidence of acute rejection, constitutes an early test for chronic rejection. When its pathological rise is compared to the results of histology (presence or absence of RC), it shows a sensitivity of 0.94 and a specificity of 0.93.

Acute Disease↗
PubMed1994

Clinical and molecular study of DiGeorge sequence.

DiGeorge sequence (DGS) is a developmental field defect of the third and fourth pharyngeal pouches. The cardinal features of the syndrome are hypo- or aplasia of the thymus and parathyroids, congenital heart defect of the conotruncal type and characteristic facial dysmorphism. Such a pattern of malformations has been associated with various conditions but it is now well established that most cases of DGS are due to haplo-insufficiency of the chromosome 22q11 region. We report here a series of 16 patients, including a familial case. Minimal criteria for inclusion in this series were two or more of the following features: conotruncal heart defect, hypocalcaemia, hypoplastic/absent thymus and typical facial dysmorphism. Molecular analysis with specific probes of the 22q11 region was conducted in all patients according to two methods, fluorescent in situ hybridization and DNA dosage analysis. A deletion was found at the molecular level in all patients. We emphasize the fact that clinical analysis remains an important step of the diagnosis. The implication of these molecular techniques on diagnosis, prognosis and genetic counselling of DGS are discussed.

Child, Preschool↗
PubMed1994

Thallium perfusion and myocardial hypertrophy in transplanted heart recipients with normal or near-normal coronary arteriograms.

In patients with hypertrophic cardiomyopathy or systemic hypertension, exercise thallium perfusion defects have been observed but without significant angiographic stenoses. Hypertension and myocardial hypertrophy are common in transplanted heart recipients, and the aim of this study was to determine if exercise thallium scintigraphy false-positives are frequent in transplanted heart recipients. Thirty-four transplanted heart recipients were evaluated by exercise thallium single emission computed tomography and subsequently had a normal or near normal coronary arteriogram. At the time of the exercise, the patients (28 men and six women) had a mean age of 48.9 +/- 12 years and 29 had been previously treated for systemic hypertension. The mean duration between transplantation and the exercise test was 31.6 +/- 13 months. In all patients left ventricular mass was obtained by echocardiography within 3 months of thallium 201 SPECT and was > or = 130 g.m-2 in nine males and > or = 110 g.m-2 in four females. M-mode septal + posterior end-diastolic thickness was > 23 mm in 14 patients, all of whom had been previously treated for systemic hypertension. These patients were older and endured a longer period during which the heart was kept cold but ischaemic before being grafted ('cold ischaemia') but a shorter exercise duration than patients without left ventricular hypertrophy. During exercise testing, 26 of 34 patients achieved at least 80% of their maximal predicted heart rate and two developed significant ECG changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Hyperhomocysteinaemia in heart transplant recipients.

The aim of this study was to determine the prevalence of hyperhomocysteinaemia in cardiac transplant recipients. Three groups of subjects were studied: 27 heart transplant recipients, 14 to 63 months (mean = 36.5) after transplantation; 10 patients with moderate chronic renal insufficiency without clinical evidence of vascular disease; 17 apparently healthy individuals. Twenty-five out of 27 transplanted patients had a coronaroangiography within 6 months of homocysteine measurement. Plasma homocysteine was measured both while the subject was fasting (t0) and 6 h after administration of 0.1 g.kg-1 of methionine (t6). Hyperhomocysteinaemia was present in 14/27 fasting transplanted patients and after methionine loading. Mean plasma levels of homocysteine at t0 were higher (P = 0.03) in transplanted heart recipients (15.4 +/- 7 mumol.l-1) than in the renal patients (9.9 +/- 5 mumol.l-1) despite similar mean plasma creatinin. In eight transplanted patients with angiographic coronary abnormalities of the cardiac graft, homocysteinaemia was at t0 17.1 +/- 9 mumol.l-1 and at t6 47.8 +/- 25 mumol.l-1. In 17 transplanted patients with angiographically normal coronary arteries, plasma homocysteine levels were at t0, 13.2 +/- 4 mumol.l-1 and at t6, 46.8 +/- 25 mumol.l-1. We conclude that hyperhomocysteinaemia is common in transplanted heart recipients, and partly related to renal insufficiency. No correlation was found between hyperhomocysteinaemia and angiographic evidence of coronary atherosclerosis of the graft, but the population of the study was possibly too small to establish this correlation.

Aged↗
PubMed1993

[Lung transplantation. Contraindications and new indications].

The authors review the recent changes observed in the indications for lung transplantation. Several classical contra-indications have been alleviated or even cancelled. Chronic infection presenting as cystic fibrosis has become one of the first indications for lung replacement. Respirator-dependent patients are at an operative risk comparable to the overall results. Long-term corticosteroid therapy and pleural adhesions are no longer formal contraindications but should be approached with extreme caution. In recent years, single lung transplantation has been extended to diseases, such as emphysema and pulmonary hypertension, which were formerly indications for double-lung or heart-lung transplantation. The reasons for this include donor shortage and the better 1-year survival following single lung transplantation. The most recent development is paediatric lung transplantation. The legitimacy of redo transplantation is controversial.

Adolescent↗
PubMed1993

Double-lung transplantation in mechanically ventilated patients with cystic fibrosis.

Many lung transplant programs consider ventilator dependence as a contraindication for transplantation. Among 54 patients in whom bilateral lung transplantations for cystic fibrosis were performed by the Joint Marseille-Montreal Lung Transplant Program, 10 were ventilator dependent. Three of them died in the early postoperative period (30%): 2 as a result of cerebral anoxia and sepsis, 1 of Pseudomonas cepacia pneumonia. Two patients died at 15 and 19 months after transplantation of obliterative bronchiolitis and secondary bacterial pneumonitis. Another 2 patients in whom obliterative bronchiolitis developed underwent retransplantation with a heart-lung block; 1 of those was operated on at 12 months and is well at 29 months after his initial transplantation; the second was operated on at 34 months and died of primary graft failure. Three other patients are alive and well at 3, 11, and 14 months after transplantation. Actuarial survival at 1 year was 70%. The postoperative course and the infectious and rejection complications were no different from those in patients who underwent transplantation while spontaneously breathing. Obliterative bronchiolitis developed in 66% of patients at risk (2 of 6 patients surviving more than 6 months). We conclude that transplantation in mechanically ventilated patients with cystic fibrosis is not associated with an increase in morbidity or mortality after bilateral lung transplantation. Long-term survival, as in patients who undergo transplantation while spontaneously breathing, is limited by the development of obliterative bronchiolitis.

Adolescent↗
PubMed1992

Double-lung transplantation for cystic fibrosis. The Cystic Fibrosis Transplant Study Group.

One hundred twenty cystic fibrosis patients were accepted for transplantation. Twenty-five patients underwent double-lung transplantation. Twenty-five patients died awaiting transplantation (20.6%). There were 13 female and 12 male patients. Their mean age was 28 years (range, 7 to 34 years), and mean percentage ideal body weight was 76% (range, 58.5% to 91.9%). Most patients were hypoxic and hypercarbic. Two patients underwent tracheal anastomosis, 15 had en bloc bronchial anastomoses, and 8 had sequential single-lung transplants. Operative mortality was 16%; all deaths were related to bleeding from extensive adhesions. Actuarial survival at 1 year was 64%. Rejection and infection were frequent during the first month and decreased thereafter. Airway complications occurred in 5 patients but were amenable to laser therapy and stenting. We conclude that double-lung transplantation is an acceptable modality for the treatment of cystic fibrosis patients with end-stage lung disease. It may be a better alternative to heart-lung transplantation considering the paucity of thoracic organ donors.

Adolescent↗
PubMed1992

A simple approach to takedown of a modified Blalock shunt.

We describe a simple and rapid technique for takedown of right-sided modified Blalock shunts involving a blunt approach between the pericardium and the pleura. We have used this method successfully on either side in 47 cases.

Arteriovenous Shunt, Surgical↗
PubMed1992

Evaluation of an absorbable suture for sternal closure in pediatric cardiac surgery.

We conducted a study in a prospective fashion using 1-mm diameter absorbable sutures (polydioxanone [PDS]) for sternal closure in 50 consecutive patients, ages 5 months to 16 years, weighing 5 to 27 kg. Good wound closure and absence of any iatrogenic complications were noted. Potential benefits of this approach include disappearance of sequelae of the closure and better bone healing. This appears to be a safe alternative to standard sternotomy closure.

Child↗
PubMed1992

[Establishment of a bank of cryopreserved valve homografts and clinical use in ninety-two patients].

Good long-term results obtained with homologous valve grafts, specially for correction of congenital cardiac defects, prompted us to create a local cryopreserved homograft bank. A 5-year experience is described, including indications for harvesting, techniques of preparation, cryopreservation and thawing. During this period, 195 homografts entered the bank and 92 were used. Among these 92 clinical cases, 74 consisted of right ventricular outflow tract reconstruction (47 valved conduit and 27 monocusp bearing patch) and 17 were left ventricular outflow tract reconstructions (11 free hand aortic valve and 6 aortic root replacement). Only one case was a tricuspid replacement with a stented homograft. Short-term results, with these homografts, are satisfactory and are compared with long-term results reported in the literature. The authors insist on using very thorough techniques and constant quality control. New developments should include viability control and immunological studies.

Aortic Valve↗
PubMed1992

[Coronary disease of transplanted heart. Physiopathology, prevention].

Coronary artery disease in cardiac transplant recipients is the main cause of mortality after the first postoperative year. This atheroma has unique anatomical features with widespread infiltration of the intima by inflammatory cells. The different physiopathological hypotheses are analysed. Immunological processes are probably responsible, suggesting chronic rejection. The cytomegalovirus could be an inductive mechanism. The classical vascular risk factors probably play a role but their action is not as clear as that of immunological and viral factors. Hyperlipidaemia is a causative mechanism and the predisposing role of steroid therapy is also recognised. From the practical point of view, correction of the classical risk factors is the only available therapeutic possibility at present.

Animals↗
PubMed1991

Tricuspid atresia or severe stenosis with partial common atrioventricular canal: anatomic data, clinical profile and surgical considerations.

The anatomic findings in 11 cases of tricuspid atresia and in two cases of severe tricuspid stenosis, both combined with partial common atrioventricular (AV) canal, are presented in detail. Twelve cases were documented by postmortem examination and the diagnosis was confirmed by echocardiography and surgical observation in the one living patient. Clinical data available in nine cases and cardiac catheterization data obtained in eight are included in this report. In three cases (23%)--two with tricuspid atresia and one with extreme tricuspid stenosis--the tricuspid valve and right ventricle exhibited characteristics seen in Ebstein's anomaly. In all 13 cases, the great arteries were normally related. The ventricular septal defect(s) in 10 (83%) of the 12 postmortem cases rapidly became smaller and this resulted in marked diminution of the pulmonary blood flow and severe hypoxia. Only three of the eight patients with available cardiac catheterization and angiocardiographic data showed the scooped-out appearance of the left ventricular septal surface characteristic of AV canal defects. By contrast, two-dimensional echocardiography, available in the three most recent cases, accurately demonstrated all the defects present and represents the diagnostic method of choice. Early surgical intervention to establish a systemic to pulmonary artery anastomosis is essential for survival. More definitive surgical treatment can be achieved later by an atriopulmonary or cavopulmonary anastomosis with or without replacement of the cleft and often regurgitant mitral valve. The one living patient exemplifies this approach. This is the largest series of this unusual type of tricuspid atresia reported to date.

Cardiac Catheterization↗