Thymic function is a major determinant of onset of antibody-mediated rejection in heart transplantation.

Thymic function decreases progressively with age but may be boosted in certain circumstances. We questioned whether heart transplantation was such a situation and whether thymic function was related to the onset of rejection. Twenty-eight antithymocyte globulin-treated heart transplant recipients were included. Patients diagnosed for an antibody-mediated rejection on endomyocardial biopsy had a higher proportion of circulating recent thymic emigrant CD4+ T cells and T cell receptor excision circle levels than other transplanted subjects. Thymus volume and density, assessed by computed tomography in a subset of patients, was also higher in patients experiencing antibody-mediated rejection. We demonstrate that thymic function is a major determinant of onset of antibody-mediated rejection and question whether thymectomy could be a prophylactic strategy to prevent alloimmune humoral responses.

[ANOCOR registry]. / Le registre ANOCOR.

Anomalous aortic origin of the coronary arteries are congenital anomalies with many anatomical forms. Due to the varying risk of sudden death, these abnormalities must be classified accurately. There are still questions about the mechanism and individual risk of sudden death, the natural history of these abnormalities and the benefits of a surgical correction. Large-scale observational registries may provide more evidence-based data to practitioners caring for the patients concerned. The ANOCOR registry, the largest in size published to date, enrolled 472 patients (mean age 63 years) with 496 coronary abnormalities. The angiographic representation (with invasive coronary angiography or coronary CT angiography) according to the coronary artery and initial ectopic course could be specified with the identification of two main phenotypes: the circumflex artery (n = 235) with a retroaortic course in 97% of cases and the right coronary artery (n = 165) with an interarterial course in 89.7% of cases. Two left coronary anatomical forms have been confused by non-expert cardiologists: those with a retropulmonary or interarterial course. Sudden death related to coronary anomaly was a very rare mode of presentation (3 patients or 0.6% of the cohort) in this population with very few young patients < 35 years (11 cases or 2.3% of the cohort).

Real-time fetal magnetic resonance imaging for the dynamic visualization of the pouch in esophageal atresia.

Esophageal atresia is the principal cause of congenital esophageal obstruction. Prenatal suspicion of esophageal atresia is usually based on the presence of polyhydramnios together with an absent stomach bubble. More recently, visualization of the dilatation of the blind-ending esophagus (esophageal pouch) during fetal swallowing has been reported and proposed as the most reliable sign for predicting esophageal atresia. Improvement of radiofrequency and computer technology as well as parallel data acquisition has greatly reduced magnetic resonance (MR) scanning time, allowing visualization of the fetus in cine-mode using fast imaging employing steady-state acquisition (FIESTA). We describe the application of FIESTA sequences in fetuses with suspected esophageal atresia for visualization of the esophageal pouch using MR imaging.

Design, characterization and in vivo performance of synthetic 2 mm-diameter vessel grafts made of PVA-gelatin blends.

Since the development of the first vascular grafts, fabrication of vessel replacements with diameters smaller than 6 mm remains a challenge. The present work aimed to develop PVA (poly (vinyl alcohol))-gelatin hybrids as tubes suitable for replacement of very small vessels and to evaluate their performance using a rat abdominal aorta interposition model. PVA-gelatin hybrid tubes with internal and external diameters of 1.4 mm and 1.8 mm, respectively, composed of 4 different gelatin ratios were prepared using a one-step strategy with both chemical and physical crosslinking. By 3D Time of Flight MRI, Doppler-Ultrasound, Computed Tomography angiography and histology, we demonstrated good patency rates with the 1% gelatin composition until the end of the study at 3 months (50% compared to 0% of PVA control grafts). A reduction of the patency rate during the time of implantation suggested some loss of properties of the hybrid material in vivo, further confirmed by mechanical evaluation until one year. In particular, stiffening and reduction of compliance of the PVA-gelatin grafts was demonstrated, which might explain the observed long-term changes in patency rate. These encouraging results confirm the potential of PVA-gelatin hybrids as ready-to-use vascular grafts for very small vessel replacement.

CT angiography of the artery of Adamkiewicz with 64-section technology: first experience in children.

BACKGROUND AND PURPOSE: Preoperative localization of the artery of Adamkiewicz (AKA) may be useful in selected children in prevention of ischemic spinal complications of spinal or thoracoabdominal aortic surgery. The aim of our study was to investigate the ability of 64-section CT for assessing the AKA in children. MATERIALS AND METHODS: Forty children (mean age, 7.5 +/- 5 years) underwent thoracic imaging with a 64-section CT scanner after intravenous injection of 1.5 mL/kg of contrast agent. Volumetric reconstructions were obtained for every patient. Identification of the AKA was performed on the basis of continuity from the aorta to the anterior spinal artery with a characteristic hairpin turn. Identification of the AKA and determination of its origin and course were analyzed by 2 independent radiologists. RESULTS: The AKA was successfully visualized in 38 patients (95%). Twenty-seven (71.1%) AKAs originated on the left side, whereas 11 (28.9%) originated on the right side. It was seen to originate at the level of the left 5th intercostal artery in 1 patient, the left 8th in 4, the left 9th in 15, the left 10th in 5, the left 11th in 2, the right 8th in 2, the right 9th in 6, the right 10th in 2, and the right 12th in 1. CONCLUSION: Sixty-four-section CT angiography depicted the AKA in a very high percentage (95%) of children. The results of this study suggest that 64-section CT angiography is a viable noninvasive technique that could be an alternate to selective angiography for delineating the AKA.

[Anomalous left main coronary artery with an inter-aorto-pulmonary trajectory: diagnostic value of 64-slice CT scan with cardiac synchronisation]. / Anomalie de naissance du tronc coronaire gauche avec un trajet interaortopulmonaire: apport du scanner 64 coupes avec synchronisation cardiaque.

Anomalous left coronary artery arising from the right sinus with an inter-aorto-pulmonary trajectory is a classical cause of sudden death and myocardial ischaemia in young adults. The mechanism is compression of the coronary during physiological dilatation of the great arteries on exercise. The authors report the case of a 12 year old child who had syncope on effort preceded by angina due to this malformation. The CT scan with 3-D reconstruction confirmed the diagnosis and the interarterial trajectory of the left coronary artery and the anatomical relationships with the vessels at the base of the heart. Cardiac CT scan is the investigation of choice for diagnosis and preoperative work-up of congenital coronary anomalies. In the authors' experience, the investigation is performed systematically when an anomalous coronary artery is suspected, in addition to echocardiography and instead of conventional coronary angiography.

[Treatment-related cardiotoxicity in childhood cancer survivors: Risk factors and follow-up]. / Facteurs de risque et surveillance à long terme des complications cardiaques après traitement pour un cancer pendant l'enfance.

Anthracycline-induced cardiotoxicity (ACT) is a severe complication in children and young adults that may lead to congestive heart failure. Some risk factors have been identified: high anthracycline cumulative dose, high radiation dose delivered on the cardiac area, or young age during the treatment. Primary prevention is not clearly defined in children. The dexrazoxane iron chelator seems to be interesting based on its short-term cardioprotective property in patients receiving doxorubicin-containing regimens. However, its long-term benefits remain to be determined, as well as the risk of secondary cancer. Childhood cancer survivors treated with anthracyclines are annually followed in the long-term. Trans-thoracic echocardiography is classically performed every 2 to 5 years for assessing the ventricular hemodynamics and function. Recent modern techniques including echocardiography with strain assessment and cardiac MRI seems to be promising for an early detection of myocardial impairment. Further studies are mandatory for validating their usefulness in the setting of anthracycline-induced cardiomyopathy. Recently, ACT predisposing variants in genes involved in oxydative stress and in metabolism and transport of anthracyclines have been identified. Their use in clinical practice could improve ACT risk stratification of children treated with anthracyclines-containing regimens. Predictive models combining replicated genetic variants and clinical factors need to be validated with the challenge to identify patients at high risk of cardiomyopathy. The objective is to personalize treatment strategy according to individual genetic background.

[Mycoplasma pneumoniae myopericarditis in children]. / Myopéricardite à Mycoplasma pneumoniae chez l'enfant.

Mycoplasma pneumoniae myocarditis is a rare condition, potentially very serious and seldom described in children. It is classically attributed to direct invasion or to an indirect immunological mechanism. The authors report the case of a 10 year old boy with myopericarditis, proved by authentic seroconversion, complicating congenital mitro-aortic valvular disease. In this case, the spectacular response to steroid therapy was in favour of an indirect immunological causal mechanism of the left ventricular dysfunction and pericardial involvement.

[Spontaneous idiopathic chylopericardium in childhood]. / Chylopericarde idiopathique spontané de l'enfant.

Here we report a case of a primary idiopathic chylopericardium in a 13 years old child. Pericardial effusion was diagnosed because the child suffered chest pain and fatigue. Pericardial drainage was performed and 800mL of chylous fluid was evacuated. Extensive investigations were performed but no cause could be found. Thoracic CT scan, lymphoscintigraphy and MRI did not evidence any communication between the thoracic duct and pericardium. After 2 recurrences of pericardial effusion while the child was on a medium chain triglycerides regimen, it was decided to ligate the thoracic duct and to do a partial pericardectomy. The result was excellent with complete resolution of the pericardial effusion and no recurrence since 3 years.

[Does hypertension need treatment following correction of coarctation in childhood?]. / Faut-il traiter l'hypertension artérielle après cure de coarctation dans l'enfance?

Does hypertension need treatment following correction of coarctation in childhood? The results of the surgical repair of aortic coarctation (CoA) are excellent. Prenatal diagnosis of this defect is made in 40% of the cases and this allowed a reduction of preoperative mortality. Beside these successes, patients who underwent a CoA repair in infancy remain at high risk for resting hypertension (HT) later in life. Indeed, half of the adolescents are hypertensive and 2/3 of the patients around 30 years. This HT is responsible for an increased mortality mostly related to cardiovascular events. Screening for HT and its risk factors is the main objective of the follow-up. Some residual anomalies such as recoarctation or hypoplasia of the horizontal aorta may be treated either by surgery or by interventional catheterisation. Recently, new contributors to hypertension have been identified such as abnormal geometry of the aortic arch or alteration of the mechanical properties of the arterial wall. In a given patient, the co-existence of vascular dysfunction and abnormal geometry of the aortic arch confers a high risk for HT. The indications to treat exercise HT or the type of antihypertensive drug to be given remain unsolved questions. Prevention may rely on substantial modifications of the surgical techniques to optimise the aortic arch geometry. The indications to correct abnormal geometries at high risk without recoarctation are not yet defined. The long-term benefit of either preventive or curative strategies might be difficult to evidence and will probably need the analysis of intermediate markers such as vascular function and left ventricular hypertrophy.

[Transcatheter exclusion of a giant aneurysm of the left pulmonary artery using covered stents]. / Exclusion d'un anévrisme géant de l'artère pulmonaire gauche par cathétérisme interventionnel: utilisation de stents couverts.

An 11 year-old boy with an Alagille syndrome was referred for an urgent echocardiography because of new onset of febrile hemoptysis. Follow-up in our institution to that point had shown severe hypoplastic pulmonary arteries. The diagnosis of tricuspid endocarditis complicated by pulmonary embolisms and aneurysm of the left pulmonary artery was done. Despite effective antiobiotics, the evolution was marked by rapid progression in size of the left pulmonary aneurysm. Since the surgery was not an option because of high risk of death, this aneurysm was treated by a trans-catheter technique using covered stents (CP stents, Numed Inc). Its exclusion allowed to stop its progression in size and to avoid its rupture.

[Multislice CT scan in congenital heart disease]. / Le scanner volumique dans les cardiopathies congénitales.

The management of congenital cardiovascular malformations is a diagnostic challenge. It requires accurate assessment of the intra- and extra-cardiac malformations. Three-dimensional imaging by the multislice CT scanner is now a routine investigation for congenital heart disease, complementary to echocardiography, and, increasingly, an alternative to conventional angiography. Three dimensional imaging is particularly useful in the diagnosis of complex congenital heart disease, in the preparation of complex investigations of interventional cardiac catheterisation and the postoperative evaluation of surgical repair. This report describes the different acquisition protocols adapted for children and illustrates the present role of volumic CT scanner in congenital heart disease by clinical examples of everyday clinical practice.

Modern Imaging of Myocarditis: Possibilities and Challenges / Moderne Bildgebung bei Myokarditis: Möglichkeiten und Herausforderungen

UNLABELLED: Myocarditis is known as the chameleon of cardiac diseases. The symptoms and the course of disease vary greatly so that it is often challenging to establish a diagnosis. Early and accurate diagnosis is of utmost importance, since myocarditis is one of the leading causes of sudden cardiac death in young adults and represents an important precursor to dilated cardiomyopathy. Due to the constraints of the routinely used diagnostic approach, including clinical history and examination, laboratory testing, and electrocardiogram, different imaging modalities have emerged over the last decades as contributors to the noninvasive diagnosis of myocarditis. With this interdisciplinary review we would like to present the current state-of-the-art imaging of myocarditis across all available imaging modalities (i. e., echocardiography, cardiac magnetic resonance, cardiac computed tomography, and nuclear medicine). Furthermore, we present novel imaging techniques that might become useful in the near future for easier and more accurate diagnosis of this highly relevant disease. KEY POINTS: • Different imaging modalities are increasingly used in the diagnostic workup of myocarditis. • Several emerging imaging techniques are currently on the way to becoming part of the clinical routine. • This review summarizes the diagnostic value of echocardiography, CMR, CT, and nuclear medicine imaging. • There is special focus on the possibilities and challenges of novel imaging tools within the different modalities.

MR imaging of Schmorl's nodes: Imaging characteristics and epidemio-clinical relationships.

PURPOSE: The purpose of our prospective study was to assess the presentation of Schmorl's nodes (SN) on magnetic resonance imaging (MRI) and investigate their possible association with demographic and clinical findings. MATERIALS AND METHODS: Three hundred and thirty-three patients were prospectively included. Thirteen (3.9%) patients were excluded because of contraindication to MRI and/or Scheuermann's disease. The final study population included 320 patients. T1-weighted and short TI inversion recovery sequences were performed to assess SN prevalence, the vertebral level and their anatomical distribution in vertebra. Medical history was recorded focusing on previous diseases including degenerative, rheumatoid and neoplastic disease, and any existing spinal traumatism. Epidemiological information was also obtained, including age, gender, ethnicity, professional and sporting activity. RESULTS: The final study population included 320 patients (172 men, 148 women) with a mean age of 54 years±17.5 (SD) (range: 19-87 years). A total of 421 SN were found in 158/320 patients (49.4%). SN were localized in thoracic spine for 48%, in lumbar spine for 46% and cervical spine for 6%. The middle part of the thoracic vertebra was the most affected area (80%), mostly in the middle superior endplate (41%). SN were more frequently observed in manual workers who worked more than 10 years (P<0.0001) and less frequently in patients of the 30-39-year-old age group (P=0.0048). No significant associations were found with gender (P=0.17) and remarkable medical history (P=0.21). SN were less frequently observed in patients with sport activities of 1-5hours/week (P=0.04) and those with an African origin (P<0.0001). CONCLUSION: Our study suggests a potential role for ethnical and physical factors in the pathogenesis of SN. Furthers studies are mandatory to evaluate their clinical relevance, especially in patients such as Caucasian manual workers in whom SN have a high prevalence.

[Aortic arch shape and flow dynamics]. / Architecture de la crosse aortique et circulation des fluides.

Post-operative deformation of the aortic arch architecture is associated with an increased risk of hypertension following correction of coarctation. In addition to morphological analysis, MRI allows a functional analysis of the thoracic aorta. We report three examples which illustrate the direct relationship between aortic arch morphology and blood flow in the thoracic aorta.

[Relationship between aortic arch shape and blood pressure response after coarctation repair]. / Relation entre l'architecture de la crosse aortique et la pression artérielle après cure de coarctation.

The mechanisms of secondary hypertension after repair of coarctation of the aorta are not well understood. Abnormalities of the architecture of the aortic arch and their consequences on blood pressure have not been studied. In order to study the relationship between abnormalities or aortic arch architecture and resting blood pressure ninety-four patients without re-coarctation were followed up prospectively from 1997 to 2004 (mean age 16.9 +/- 8.1 years; mean weight 57.5 +/- 18.3 Kg; interval since surgery 16.3 +/- 5.4 years). All underwent MRI angiography of the thoracic aorta which enabled the abnormalities to be classified in 3 groups: gothic arch, crenellated arch and roman arch. Twenty-four patients (25.5%) were hypertensive and 70 (74.4%) normotensive. There were 40 gothic arches (42.5%). 14 crenellated arches (15%) and 40 roman arches (42.5%). Gothic arches were more commonly observed in the hypertensive patients (18/40, [45%, 95% CI 31-62]) than the crenellated arches (4/14, [28.5%, 95% CI 7-48]) or the roman arches (2/40, [5%, 95% CI 2-12]). Only the gothic arch was independently correlated with hypertension on multivariate analysis. The authors conclude that gothic deformation of the aortic arch is an independent predictive factor of hypertension in patients operated for coarctation with an excellent result on the isthmic region. Patients with a gothic appearance of their aortic arch should be followed up closely.

Establishment of diagnostic reference levels in cardiac CT in France: a need for patient dose optimisation.

The objective of this study was to propose diagnostic reference levels (DRLs) for coronary computed tomography angiography (CCTA), in the context of a large variability in patient radiation dose, and the lack of European recommendations. Volume Computed Tomography Dose Index (CTDIvol) and dose-length product (DLP) were collected from 460 CCTAs performed over a 3-month period at eight French hospitals. CCTAs (∼50 per centre) were performed using the routine protocols of the centres, and 64- to 320-detector CT scanners. ECG gating was prospective (n = 199) or retrospective (n = 261). The large gap in dose between these two modes required to propose specific DRLs: 26 and 44 mGy for CTDIvol, and 370 and 970 mGy cm for DLP, respectively. This study confirms the large variability in patient doses during CCTA and underlines the need for the optimisation of cardiac acquisition protocols. Availability of national DRLs should be mandatory in this setting.

Aminoguanidine: a drug proposed for prophylaxis in diabetes inhibits catalase and generates hydrogen peroxide in vitro.

Aminoguanidine (AG) has been proposed as a drug of potential benefit in prophylaxis of the complications of diabetes. We show here that AG irreversibly inhibits catalase with an efficacy similar to aminotriazole. AG also produces hydrogen peroxide, in a transition metal-catalysed process which may be partially dependent upon prior hydrolysis of AG to semicarbazide and hydrazine. These observations may be of importance in proposals for the long term administration of AG in diabetes.

Thioctic (lipoic) acid: a therapeutic metal-chelating antioxidant?

Thioctic (alpha-lipoic) acid (TA) is a drug used for the treatment of diabetic polyneuropathy in Germany. It has been proposed that TA acts as an antioxidant and interferes with the pathogenesis of diabetic polyneuropathy. We suggest that one component of its antioxidant activity requiring study is the direct transition metal-chelating activity of the drug. We found that TA had a profound dose-dependent inhibitory effect upon Cu(2+)-catalysed ascorbic acid oxidation (monitored by O2 uptake and spectrophotometrically at 265 nm) and also increased the partition of Cu2+ into n-octanol from an aqueous solution suggesting that TA forms a lipophilic complex with Cu2+. TA also inhibited Cu(2+)-catalysed liposomal peroxidation. Furthermore, TA inhibited intracellular H2O2 production in erythrocytes challenged with ascorbate, a process thought to be mediated by loosely chelated Cu2+ within the erythrocyte. These data, taken together, suggest that prior intracellular reduction of TA to dihydrolipoic acid is not an obligatory mechanism for an antioxidant effect of the drug, which may also operate via Cu(2+)-chelation. The R-enantiomer and racemic mixture of the drug (alpha-TA) generally seemed more effective than the S-enantiomer in these assays of metal chelation.

Activation of aldose reductase in rat lens and metal-ion chelation by aldose reductase inhibitors and lipoic acid.

Sorbitol formation in rat lenses incubated with high levels of glucose was related to activation of aldose reductase (AR). The hyperglycaemia-activated aldose reductase was inhibited by alpha-lipoic (thioctic) acid, O-phenanthroline and aldose reductase inhibitors (ARIs) including Zeopolastat (ZPLS), Sorbinil (SBN) and AL-1576. This study also examined ARIs for the ability to chelate metal ions. We found that ARIs suppress copper-dependent ascorbate oxidation, lipid peroxidation and hydrogen peroxide production in erythrocytes. ARIs also increased partition of copper ions into noctanol, which indicates formation of lipophilic complexes. Our data support the hypothesis that transition metals may be involved in activation of the polyol (aldose reductase) pathway. Also, ARIs function as metal-chelating antioxidants that may contribute to their therapeutic role for diabetic complications.