Oxygen-isotope evidence for recycled crust in the sources of mid-ocean-ridge basalts

Mid-ocean-ridge basalts (MORBs) are the most abundant terrestrial magmas and are believed to form by partial melting of a globally extensive reservoir of ultramafic rocks in the upper mantle. MORBs vary in their abundances of incompatible elements (that is, those that partition into silicate liquids during partial melting) and in the isotopic ratios of several radiogenic isotope systems. These variations define a spectrum between 'depleted' and 'enriched' compositions, characterized by respectively low and high abundances of incompatible elements. Compositional variations in the sources of MORBs could reflect recycling of subducted crustal materials into the source reservoir, or any of a number of processes of intramantle differentiations. Variations in (18)O/(16)O (principally sensitive to the interaction of rocks with the Earth's hydrosphere) offer a test of these alternatives. Here we show that (18)O/(16)O ratios of MORBs are correlated with aspects of their incompatible-element chemistry. These correlations are consistent with control of the oxygen-isotope and incompatible-element geochemistry of MORBs by a component of recycled crust that is variably distributed throughout their upper mantle sources.

Suspected acute coronary syndrome in a theater of operations: first management, medical evacuation, and final diagnosis: experience of the French Medical Army.

OBJECTIVE: to evaluate the treatment of the acute coronary syndrome (ACS) among soldiers stationed on a theater of operations by structures usually conceived to treat combat-related trauma. METHODS: We performed a retrospective study involving the whole medical evacuations out of a theater of operations to the benefit of the French Armed forces, for a suspected diagnosis of ACS. RESULTS: 35 patients were included in this study with 20 for a diagnosis of persistent ST-Segment Elevation Myocardial Infarction (STEMI). Only an active smoking defined a population at risk in these high medical selective soldiers. The agreement between the initial and the final diagnosis was excellent for STEMI but remains perfectible for NSTEMI. CONCLUSION: the medical structures deployed in a theater of operations were able to provide first treatment in ACS. The use of powerful diagnosis test, like troponine assay, must allow a better selection of the patients justifying a medical evacuation.

[Cardiac toxicity of catecholamines. Report of two cases]. / Toxicité myocardique des catécholamines: à propos de deux observations.

INTRODUCTION: The role of catecholamines in the cardiac expression of pheochromocytoma is well-known. The physiopathology of the syndrome of Tako-tsubo remains more unclear. EXEGESIS: We describe 2 clinical cases of acute coronary syndrome with left ventricular dysfunction and no coronary artery stenosis. The first, a syndrome of Tako-tsubo, also known as transient left ventricular apical ballooning syndrome, is characterized by transient wall-motion in the absence of obstructive epicardial coronary disease. The second is a pheochromocytoma with myocardial suffering during hypertension crisis. Through the similarities of these 2 observations, we discuss the physiopathological assumptions to explain the syndrome of Tako-tsubo by underlining the essential place of the catecholamine hypersecretion. CONCLUSION: Syndrome of Tako-tsubo and pheochromocytoma are 2 distinct clinical entities. The link between these 2 affections is probably the pathogenic role in cardiac toxicity with the catecholamines.

[Vascular approaches and closure devices for percutaneous coronary intervention]. / Les voies d'abord et systèmes de fermeture dans l'angioplastie coronaire.

The choice of a transradial or transfemoral approach remains a pivotal decision in percutaneous coronary angioplasty. We discuss here the varying criteria leading to a rational choice in the arterial access choice. Since the emergent transradial approach in France has led to a dramatic reduction in local vascular complications, we also discuss the remaining place of femoral approach and the usefulness of femoral percutaneous closure devices.

[Saphenous graft angioplasty]. / Angioplastie des pontages veineux.

In our daily practice the rate of saphenous graft angioplasty is less than 5%. This kind of angioplasty is more complex with a higher rate of complications in known fragile patients. Some technical trips and tricks are necessary to easily perform these angioplasties. Main difficulties are the extension of saphenous graft lesions, the risk of distal embolism, coronary slow or no flow and the high rate of restenosis. Pharmacological treatment is disappointing with no efficacy of the Gp IIb-IIa blockers. Otherwhise the use of protection devices is clearly effective and must be used when it is technically possible. With the use of bare metal stents in saphenous graft angioplasty the rate of restenosis is very high. There are some encouraging results with drug eluting stents. But we are still now not allowed to use them in this indication in our daily practice.

[Increased secretion of Nt-proBNP immediately after percutaneous coronary intervention: about 90 cases]. / Elévation de la sécrétion du Nt-proBNP dans les 24 heures suivant une angioplastie coronaire: à propos de 90 cas.

Nt-proBNP have emerged as useful biomarker for the diagnosis and prognostic of heart failure but also recently in acute coronary syndrome. Myocardial ischemia is probably an important stimulus for Nt-proBNP release. Transient myocardial ischemia is inducing by balloon inflation during percutaneous coronary intervention (PCI). The authors propose to determine the Nt-proBNP secretion after uncomplicated coronary intervention in patients with preserved cardiac function. Ninety patients were enrolled in this study. Plasma Nt-proBNP was increased significantly from 135.5 to 157.8 pg/ml and 202.5 pg/ml at 8 and 24 hours following PCI, respectively. History of myocardial infarction and complex lesions were the most powerful predictors of higher Nt-proBNP peak concentration. Prognostic value must be evaluated in larger studies.

[Intracoronary administration of antithrombotic agents via a perfusion balloon catheter in patients with ST-segment elevation myocardial infarction presenting with massive intraluminal thrombus and failed aspiration]. / Apport de l'administration intracoronaire d'antithrombotiques par cathéter à ballon de perfusion en phase aiguë d'infarctus du myocarde avec thrombus massif et échec de la thromboaspiration.

BACKGROUND: Massive intracoronary thrombus is associated with adverse procedural results including failed aspiration and unfavourable reperfusion. We aim to evaluate the effect of the intracoronary administration of antithrombotic agents via a perfusion catheter in patients with ST-segment elevation myocardial infarction (STEMI) presenting with a large thrombus burden and failed aspiration. METHODS: We retrospectively analyzed the thrombus burden, the TIMI grade flow, and the myocardial Blush in 25 consecutive STEMI patients with a large thrombus burden and failed manual aspiration, who received intracoronary infusion of glycoprotein IIb/IIIa inhibitors (N=17) or bivalirudine (N=8) via a 6F-infusion catheter (ClearWay™ RX) RESULTS: Mean age was 67±14 years, 16 patients (64 %) presented with anterior STEMI, and 7 (28 %) with cardiogenic shock. Immediately after intracoronary infusion, the TIMI flow grade improved of 2 grades in 7 patients (28 %), and 1 grade in 14 (56 %), a complete resolution of the thrombus was observed in 9 patients, and a >50 % resolution in 12. Blush was improved of 3 grades in 15 patients (60 %), of 2 grades in 7 (28 %), and Blush grade 0 remained in 3. At the end of procedure, we observed normal TIMI 3flow in most patients (92 %), a complete resolution of thrombus in 80 %, and a Blush grade 3 in 68 %. CONCLUSIONS: In STEMI patients presenting with a large thrombus burden and failed aspiration, intracoronary administration of glycoprotein IIb/IIIa inhibitors or bivalirudin via the perfusion catheter ClearWay™ RX significantly reduced the thrombus burden and improved the TIMI flow and the Blush grade, without bleeding.

[Anticoagulation strategy in coronary angioplasty]. / Stratégie d'anticoagulation au cours de l'angioplastie coronaire.

The explosion in the number of angioplasties rapidly imposed a necessary compromise between effective anticoagulation during the procedure to prevent thrombotic phenomena, related mainly to the use of foreign intravascular materials, and the limitation of haemorrhagic complications, the corollary to this type of treatment. Modern universally accepted protocols, the fruit of over 20 years' experience, are described by the authors. However, the constant progress in the management of acute coronary syndromes and the increasing use of new anticoagulant and antiaggregant molecules imply an obligatory adaptation of the use of heparin in all its forms, which should be based on irrefutable scientific evidence: the preliminary results are then discussed. Finally, future trends will be outlined with the development of new, better targeted sites of anticoagulation which may provide optimal safety in the medium term.

[Coronary dissection associated with exercise: unusual cause of myocardial infarction]. / La dissection coronaire liée à l'effort: une cause rare d'infarctus du myocarde.

A case of coronary artery dissection occurring immediately after weight training is reported in a young adult with no cardiovascular risk factor. The patient had an anterior myocardial infarction treated by primary coronary angioplasty and stenting. Other rare but similar cases have been reported in the literature with a generally poor prognosis. The physiopathological mechanisms acting during exercise or the immediate recovery period are thought to be either trauma of the arterial wall by the myocardium itself or coronary artery spasm. Present management of this condition is based on coronary angioplasty with stenting.

[Coronary angioplasty using 5 or 6 F guide catheters. Results of a comparative, monocentric, prospective randomized study]. / Angioplasties coronaires par cathéters guides 5 ou 6 F. Résultats d'une étude comparative, monocentrique, prospective, randomisée.

Improvement of balloon and stent profile allows to use smaller-diameter catheters to avoid vascular complications by reduce the size of puncture site. First studies using 5 F guiding catheters showed good results in term of safety and feasibility. The authors performed a prospective, randomised study to define exactly the place of such small catheter compared to 6 F approach. One hundred forty eight patients were randomised, 77 in the 5 F group. The success rate per lesions was not significantly different but was less in the 5 F group (91.1 vs 96.5%). The crossover to 6 F allows good results in mainly cases. Limitations are unstable back up, worse opacification, and inability to use covered stent and to treat bifurcation lesions. There are no advantages in term of vascular complications. So, these catheters seem to be limited to treat simple lesion, allowing using the same sheath immediately after coronarography, but these results must be confirmed in a large, multicentric study.

Clinical and psychological classification of non-specific low-back pain. A new study in primary care practice.

This study aimed to explore the clinical and psychological features of non-specific low-back pain (LBP), and to evaluate a classification of patients based on the relationship between psychological disturbances and LBP clinical presentation. An unselected population of consecutive patients (n = 262) complaining of low-back pain to primary care physicians of the Epidemiology Team of the French Rheumatology Society, in October and November 1991, was studied. Measures included a standardized clinical evaluation of the back and a psychological assessment using the General Health Questionnaire. Ninety nine patients (38%) were classified as having a psychological disorder. The following symptoms: psychological precipitating event, permanent pain at night, diffuse spinal pain, pain increased by changing climate, pain increased by psychological factors, dysesthesias in the back, non-anatomical tenderness, were found to be closely associated with the existence of psychological disorder. Correspondence and cluster analyses provided support for the four-group classification of low-back pain previously devised. This classification may be interpreted through the relationships between psychological disturbances and the back clinical features. Although the study was mainly descriptive and used a cross sectional design, its results underline the importance of psychological influence on low-back pain presentation, and suggest the interest of a psychiatric assessment in low-back pain patients. Psychological disorders appear to be frequent in these patients and specific management of these disorders may prove useful.

[Alcohol and rhythm disorders]. / Alcool et troubles du rythme.

Cardiovascular disease is the main cause of mortality in chronic alcoholics. There is a clear association between excessive alcohol consumption and the risk of sudden cardiac death. The pro-arrhythmogenic effect of ethanol could be responsible for some of these cases of arrhythmia and sudden death in subjects with an alcoholic cardiomyopathy and also in those with an apparently normal heart. In any case of supraventricular or ventricular arrhythmia in a chronic alcoholic or in an occasional heavy drinker, the potential role of alcohol consumption in the initiation of these disorders should be considered. In all cases, patient management consists of detoxification and abstaining from alcohol consumption, but the withdrawal period is particularly critical as regards the risk of ventricular arrhythmias.

[Iodic allergic reaction with vasospasm occluded coronary during coronarography]. / Allergie aux produits de contraste iodes compliquée d'un spasme coronarien occlusif au cours d'une coronarographie: à propos d'un cas.

Coronary vasospasm is infrequent during anaphylaxis reaction. The authors describe a severe coronary spasm following iodine allergic reaction and then should to explain the physiopathology of this complication.

[Detection of induced myocardial ischemia during stress cardiovascular magnetic resonance]. / Détection de l'ischémie myocardique par l'IRM myocardique de stress.

In the past decade, cardiovascular magnetic resonance (CMR) has evolved considerably. Its clinical applications enable the diagnosis and prognostic assessment of patients with ischemic heart disease. CMR is safe, with absence of any ionizing radiation, and offers the greatest information from a single test, allowing the assessment of myocardial morphology, myocardial function and viability. Stress-CMR can be used for detection and quantification of ischemia. This article analyses the technical approach, the limits and reviews the available literature about diagnostic performance of stress CMR testing and its results in the prognostication of cardiac patients. With further improvements in CMR techniques and the establishment of a standardized study protocol, stress-CMR will play a pivotal role in managing patients with ischemic heart disease.

[Optical coherence tomography applied to vessels: a bright future]. / L'OCT appliquée aux vaisseaux : un avenir prometteur.

Optical Coherence Tomography (OCT) is a new imaging technique recently applied to coronary and is based on the diffusion and reflection of an infrared spectrum. With a resolution 10 times higher than that of IVUS, it allows an analysis of the atherosclerotic plaque and its components, indicating its possible vulnerable character, and can identify the culprit lesion and the presence of thrombus in the course of acute events. It allows quality control of good apposition of stents to the wall and essentially tracks the downstream dissection. In the longer term, it evaluates the endothelisation and in-stent restenosis. Its scope thus extends to basic research and the pharmaceutical industry where it plays a new reference tool in the monitoring of atherosclerotic plaques and stents with drug treatment. This invasive imaging technique is limited by its cost and artifacts but new generation OCT can better overcome them. The OCT appears as a promising intravascular imaging technique whose feasibility and clinical applications, however, require confirmation by randomized clinical trials to better define its place in the cardiac catheterization lab.

[Are very old patients good candidates for percutaneous coronary intervention? A monocentric retrospective study]. / Les patients très âgés sont-ils de bons candidats à l'angioplastie coronaire? Une étude rétrospective monocentrique.

AIM: To determine the feasibility of percutaneous coronary intervention (PCI) in very old patients. BACKGROUND: The elderly are a growing population with a high prevalence of ischemic heart disease and then subsequent possibility to benefit from coronary interventions. METHOD: We have conducted a retrospective study using our PCI database since January 2000. Population characteristics, clinical presentation, type of lesions, technical procedure, immediate results and in hospital outcome are compare between patients older than 85 and the other. RESULTS: Between January 2008 and March 2009, 3130 patients benefit from coronary angioplasty. Among them, 85 patients were older than 85. There were more female in this group (24.7 vs. 14.3%, P=0.007), but no difference in cardiovascular risk profile. The older was more symptomatic (acute coronary syndrome: 59.52 vs. 44%, P=0.004; silent ischemia: 3.6 vs. 25.7%, P=0.000003). The ejection fraction was worse (EF<55%: 29.4 vs. 14.5%, P=0.0001). The lesion was more complex (B2 and C: 67.2 vs. 57.1% P=0.027) and concern more often the left descending artery (85.9 vs. 57.1%, P=0.000001). The technical success was similar in the two groups (93.28 vs. 94.32%, P=0.34) with similar rate of per procedure complications (2.35 vs. 1.5%, P=0.37). Nevertheless, the in-hospital rate mortality was higher in the older patients (7 vs 1.38%, P=0.0014). CONCLUSION: PCI is safe and safety in very old patients despite significant but acceptable increasing in-hospital mortality due to more severe disease and co morbidities. Further evaluations are necessary in order to edict specific recommendations.