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Résumé: La cardio-oncologie requiert une connaissance fine de la cardiotoxicité des traitements anticancéreux, de leur mécanisme et de leur diagnostic pour mieux les prendre en charge. Les traitements anticancéreux sont responsables de dommages cardiaques à différentes échelles, jusqu'à une altération microvasculaire. Leur cardiotoxicité repose aujourd'hui principalement sur l'altération de la fraction d'éjection ventriculaire gauche (FEVG). L'imagerie de perfusion cardiaque cherche à rendre compte de l'apport de l'oxygène et des nutriments aux tissus au travers du flux sanguin, suggérant ainsi l'évaluation de la microcirculation coronaire. Cette imagerie de perfusion cardiaque peut être réalisée en pratique clinique par imagerie nucléaire ou imagerie par résonance magnétique (IRM) cardiaque. Dans cette mini-revue, nous exposons la cardiotoxicité de différents traitements anticancéreux et décrivons l'évaluation de la perfusion myocardique pour détecter précocement cette cardiotoxicité avant toute altération de la FEVG. Cardio-oncology requires a good knowledge of the cardiotoxicity of anticancer drugs, their mechanisms and diagnosis for better management. Anticancer drugs are responsible of cardiac damages at different levels that could involve microvascular dysfunction. Anticancer drugs cardiotoxicity are currently mainly based on left ventricle ejection fraction alteration (LVEF). Cardiac perfusion imaging involves assessing the delivery of oxygen and nutrients to tissues through blood flow, and thus suggest assessment of the coronary microcirculation. This can be realized in clinical practice by nuclear imaging or cardiac magnetic resonance imaging. In this mini-review, we provide a comprehensive overview of the cardiotoxic effects of anticancer drugs and describe myocardial perfusion approaches to detect them before overt LVEF impairment. [ABSTRACT FROM AUTHOR]

Leriche syndrome or aortoiliac occlusive disease is a particular obliterative arterial disease of the lower limbs, consisting of thrombotic occlusion of the aortoiliac junction. We here report the case of a 20- year-old female patient with no particular past medical history, presenting with acute lower limb ischemia. Lower extremity echo Doppler showed overall decrease in arterial blood flow without visualization of endoluminal material. Lower limb angioscaner showed arterial thrombosis of the abdominal aorta extended to bilateral external iliac arteries. The patient subsequently underwent aortic-bi-iliac bypass surgery with good evolution as well as assessments for possible thrombogenic mechanism. [ABSTRACT FROM AUTHOR]

Résumé: Objectifs: Bien que l’étiologie de l’ostéonécrose de la tête fémorale dépende des altérations du flux sanguin osseux, les fibres nerveuses vasorégulatrices du système nerveux sympathique et sensoriel n’ont jamais été étudiées dans l’os des patients atteints d’ostéonécrose. Le but de cette étude est d’analyser la densité des fibres nerveuses sympathiques et sensorielles dans la tête fémorale et par comparaison dans le périoste adjacent et le synovium de la hanche chez les patients atteints d’ostéonécrose. Méthodes: Des techniques de marquage par immunofluorescence ont été utilisées en ciblant des marqueurs spécifiques des fibres nerveuses. Un total de dix patients atteints d’ostéonécrose précoce de la tête fémorale (ARCO I-II), dix atteints ostéonécrose tardive de la tête fémorale (ARCO III-IV) et dix patients souffrant d’arthrose de la hanche a été étudié. Résultats: Dans l’os de la tête fémorale, la densité des fibres nerveuses sympathiques était plus faible lors de l’ostéonécrose précoce et tardive en comparaison de l’arthrose. Il y avait une forte prépondérance de fibres nerveuses sympathiques par rapport aux fibres sensorielles dans l’os des patients souffrant d’arthrose contrairement à l’ostéonécrose précoce et tardive de la tête fémorale. Dans le périoste, la densité des fibres nerveuses sympathiques était similaire dans les trois groupes mais la densité des fibres nerveuses sensorielles et la cellularité étaient supérieures dans l’ostéonécrose précoce en comparaison des deux autres groupes. Discussion et conclusions: À cause de l’affinité différente de la norépinephrine pour les adrénorécepteurs α (de haute affinité) et les adrénorécepteurs β (de faible affinité), la perte des fibres nerveuses sympathiques par rapport aux fibres nerveuses sensorielles dans l’ostéonécrose de la tête fémorale pourrait changer le flux sanguin de la tête fémorale (vers une vasoconstriction adrénergique α). Une densité en fibres nerveuses sensorielles et une cellularité accrues dans le périoste pourraient indiquer une réponse inflammatoire dans l’ostéonécrose précoce. [Copyright &y& Elsevier]

Abstract: Twin-to-twin transfusion syndrome (TTTS), also called twin oligoamnios polyhydramnios sequence (TOPS) complicates around 15% of monochorionic pregnancies irrespective of the mode of conception Error! Bookmark not defined. It is a hemodynamic, and probably hormonal, discordance secondary to imbalanced blood flows through the vascular anastomoses aforementioned. During the last 15 years, a lot of progress has been made in the understanding, diagnosis and treatment of TTTS. Nevertheless, many questions remain unanswered and research is still active in this domain. Fetoscopic laser coagulation of placental vessels is the only treatment addressing the pathophysiology of the syndrome as proven through a randomized controlled study against amnioreduction. This technique has definitely improved overall survival as well as the rate of neurologically intact survival but it still lacks preoperative prognostic markers. [Copyright &y& Elsevier]

Summary: Introduction: The most important factor for successful free-flap transfer and replantations is a well-executed anastomosis. The aim of this study is to assess blood flow after laser assisted arterial microanastomosis (LAMA) using a 1.9μm diode laser. Materials and methods: LAMA was performed on a series of 10 carotidis on Wistar rats. Two 10/0 stay sutures and a standard laser tissue welding technique (λ: 1.9μm; power: 120mW) were used. Similarly, a series of 10 conventional arterial anastomosis were performed (CSMA). For the two groups, contralateral non-operated carotidis were used as control. A positioning sequence, an anatomical sequence, an angiographic sequence and a flow sequence were performed 1 day after operation and then after 1, 4 and 8 weeks. Results: The arterial patency rate was 100% at the time of surgery. The mean clamping time was 7.2min in the LAMA group compared to 10.7min in the CSMA group. In the angiographic sequence, there were no aneurysms in both groups for all observation periods. At postoperative day 1, the mean loss of blood flow at the level of anastomosis in the LAMA group was 6% compared with 14% in the CSMA group. After 1, 4 and 8 weeks, there was an unhooking of the blood flow in the CSMA group: the loss of blood flow was 23%, 27% and 31% respectively, compared with 10%, 12% and 13% in the LAMA group. Moreover, one case of thrombosis was observed in the CSMA group after 1 week. Conclusion: The flow-MRI emphasizes that 1.9μm diode laser assisted microvascular anastomosis appears to be a consistent and reliable technique. These results show that 1.9μm diode laser assisted microvascular anastomosis has potential for further development in the near future. [Copyright &y& Elsevier]

Abstract: The prevalence of significant splanchnic arterial stenoses is increasing, but remains mostly asymptomatic due to abundant collateral circulation. Acute insufficiency of mesenteric arterial blood flow accounts for 60 to 70% of cases of mesenteric ischemia and results mostly from a superior mesenteric embolus. Despite major advances have been achieved in understanding the pathogenic mechanisms of bowel ischemia, its prognosis remains dismal with mortality rates about 60%. The diagnosis of acute mesenteric ischemia depends upon a high clinical suspicion, especially in patients with known risk factors. Rapid diagnosis is essential to prevent intestinal infarction. However, early signs and symptoms of mesenteric ischemia are non specific, and definitive diagnosis often requires radiologic examinations. Early and liberal implementation of angiography has been the major advance over the past 30years which allowed increasing diagnostic accuracy of acute mesenteric ischemia. CT and MR-based angiographic techniques have emerged as alternatives less invasive and more accurate to analyse splanchnic vessels and evaluate bowel infarction. The goal of treatment of patients with acute mesenteric ischemia is to restore intestinal oxygenation as quickly as possible after initial management that includes rapid hemodynamic monitoring and support. Surgery should not be delayed in patients suspected of having intestinal necrosis. [Copyright &y& Elsevier]

Abstract: This review aims at presenting a state of the art on platelet functions, not only in well-characterized hemostasis and thrombosis, but also in various domains such as inflammation, immunity, angiogenesis, source of growth factors, metastasis and vascular remodelling. This multivalent phenotype of platelets suggests new potential applications of platelets. The second objective is to present new advances in platelet formation from megakaryocytes and direct platelet release, as initially shown by our group and more recently by others. [Copyright &y& Elsevier]

Summary: The parallel evolution of lifestyles and medicine calls into question the objectives of the therapeutical relationship. Leading-edge technology, the allotransplant radically questions what curing means: is it about becoming oneself again or another person? This paper studies this dilemma from three standpoints. First, in an aesthetics perspective, the transplant surgery refers to an implicit definition of what is an acceptable body, which introduces a tension between vascular supply, immunology and beauty. How far can we favour one or the other? Secondly, in a religious perspective, transplant contributes to the mimetic desire: how can we regulate this desire in a society that increasingly values the body? Finally, from a philosophical standpoint, allotransplant questions my personal relationship with my body: beyond its technological requirements, we have to determine, in the public and private spheres, if individuals have or are bodies. What responsibility does medicine assume, as an institution and a community of agents, in this anthropological choice? [ABSTRACT FROM AUTHOR]

Summary: Performing a conventional Z-plasty on postburn scar tissue frequently leads to varying degrees of necrosis of the tips of the transposed flaps. In the conventional technique, the flaps are transposed first by anchoring the tips and then by performing the other sutures. In this order, the tips are subjected to a high degree of tension. Again, according to the conventional technique, perpendicular incisions are performed along the tips, which do not ensure the effective vascularisation of the tips in this context of postburn scarring tissue with loss of dermal blood flow. Two technical modifications are proposed: a different approach to the tension by first of all anchoring the base of the flaps and not by classical first suturing of the tips and the performance of oblique incisions away from the tips to ensure a maximum vascularisation of the subdermal fatty tissue. These two elements have allowed us to improve the results of our plasties. [Copyright &y& Elsevier]

Abstract: Purpose: We propose a diagnostic approach when facing a livedo. First, the pathophysiology of the livedo is reviewed using key articles barely quoted in the literature. Then the topic is handled in two ways. Figures and tables allow a rapid reading convenient “at the patient''s bedside”. The subject is also reviewed thoroughly, and we emphasize the intricacy of the various pathophysiological mechanisms involved for each livedo''s related disease. Diseases associated with livedo are then briefly described with emphasis on the key diagnostic features and prevalence. Usefulness of the main diagnostic procedures is discussed. Current knowledge and key points: A livedo is a usually purplish-blue erythema, reticulated (small and complete meshes) or racemosa (large broken circular segments) which is related to a slowdown of the blood flow in the dermic venules. These venules form adjacent circles communicating with each other, parallel to the skin surface. The blood flow slowdown may be due to a local vasoconstriction (vasomotor livedo) or to an arteriolar occlusion. Arteriolar occlusion may be related to blood abnormalities (thrombosis, high viscosity, embolus) or to increased parietal thickness (vasculitis, calcic deposition, intimal hyperplasia). It is not always possible to clinically distinguish a vasomotor livedo from those associated with diseases. Diagnostic procedures should be oriented by the medical history, the features of the livedo, and associated symptoms. Usefulness of the skin biopsy is usually limited to the situations where the livedo is infiltrated or necrotic. Future prospects and projects: To raise controversy about their importance and implications, some pathophysiological data are presented: intimal pseudohyperplasia in Sneddon''s syndrome and antiphospholipid syndrome, and white cell activation in essential thrombocythemia. [Copyright &y& Elsevier]

Abstract: Arteriovenous malformations are rare high-flow malformations. As other malformations, they are present at birth but may remain quiescent for many years; their flow may speed up quickly consequently on an infection, traumatism or modification of the hormonal climate. A “nidus” appears in the heart of the malformation which acts as a real “turbo” on the blood flow; vascular shunts appear creating ulcerations (vascular steal phenomenon); cardiac failure may be observed. Among all vascular anomalies, arteriovenous malformation is the most dangerous in its evolution which may be fatal. Its control requires prudence and skill. [Copyright &y& Elsevier]

Abstract: Introduction. – Women with persistently high resistance in uterine arteries have an increased risk of the subsequent development of preeclampsia. Doppler investigation provides a non-invasive method for the study of the uteroplacental blood flow. In pregnant women the antiphospholipid syndrome is associated to an increased risk of preeclampsia and complications related to uteroplacental insufficiency, and the role of uterine artery Doppler is discussed. Current knowledge and key points. – In normal pregnancy, impedance to flow in the uterine arteries decreases with gestation, as the likely consequence of the physiologic change of spiral arteries into low-resistance vessels. In women with preeclampsia or related complications, the abnormal persistence of high resistance to flow in the uterine arteries correlates with maternal and neonatal outcome. In one study including patients with antiphospholipid syndrome, a high resistance index in the uterine arteries at 22–24 weeks gestation strongly predicted the subsequent development of preeclampsia. In another study including patients with lupus anticoagulant, persistent bilateral notches at 22–24 weeks gestation may identify preeclampsia and fetal growth restriction with a high sensitivity, specificity, positive and negative predictive value. The treatment may improve the uteroplacental blood flow and is a possible confounding factor which needs further evaluation. Future prospects and projects. – In patients with antiphospholipid antibodies a higher impedance has been observed in the uterine artery, suggesting a possible vascular dysfunction precluding to impaired trophoblastic invasion and placental thrombosis, as probable mechanisms in the complications. If confirmed, these findings might have important implications for the management of these patients. [Copyright &y& Elsevier]

Abstract: Reconstruction of radionecrosis of the lower lumbar area is a challenging problem because of the difficulty of mobilization of the irradiated local tissues, absence of a reliable locoregional procedures and prolongation of the receiving vessels of the free flaps. The ideal treatment is a wide excision of the irradiated tissues and an immediate reconstruction in one step, which is better to be done by using a musculocutaneous flap. The latissimus dorsi musculocutaneous flap is ideal for this indication. The authors prefer to do the revascularization of the latissimus dorsi flap by its''thoracodorsal pedicle because of the possibility to have a high pressure blood flow which allow to use long venous bypass, the exposure of the recipient vessels at the same time of dissecting the flap and to have the anastamosis site away from the irradiated tissue. The authors are presenting their experience in treating a case of radionecrosis in the lower lumbar region with exposed vertebrae by a latissimus dorsi musculocutaneous free flap with exposed vertebrae by a latissimus dorsi musculocutaneous free flap with the lengthening of its''pedicle by two 30 cm interposition saphenous vein grafts. [Copyright &y& Elsevier]

The effects on cerebral circulation and metabolism of sevoflurane and desflurane are largely comparable to isoflurane. Both induce a direct vasodilation of the cerebral vessels, resulting in a less pronounced decrease in cerebral blood flow compared to the decrease in cerebral metabolism. This direct vasodilation seems to be dose-dependent and more pronounced for desflurane > isoflurane > sevoflurane. Many reports suggest luxury perfusion at high concentrations of desflurane. Sevoflurane maintains intact cerebral autoregulation up to 1.5 MAC. Desflurane induces a significant impairment in autoregulation, with a completely abolished autoregulation at 1.5 MAC. Both sevoflurane and desflurane (up to 1.5 MAC) maintain normal CO2 regulation. As to their effect on final intracranial pressure (ICP), both sevoflurane and desflurane revealed no increases in ICP. However, compared to intravenous hypnotics, subdural ICP is higher with volatiles because of their tendency to increase cerebral swelling after dura opening (isoflurane > sevoflurane). Several case reports have noted seizure-like movements, as well as EEG recorded seizures during induction of sevoflurane anesthesia. Especially, in children during inhalational induction with hyperventilation at a high sevoflurane concentration, severe epileptiform EEG with a hyperdynamic response were observed, which urges for caution using inhalational sevoflurane induction in children for neurosurgical procedures. Neuroprotective properties (reduced neuronal death either by necrosis or apoptosis) have been attributed to all volatile agents. However, these neuroprotective effects have been described in experimental or animal models, so their possible effect on humans remains to be proven. [Copyright &y& Elsevier]

Purpose. – Doping with EPO increases both hematocrit and performance. On the opposite, training reduces hematocrit due to plasma volume extension and overtraining both increases hematocrit and decreases performance. This apparent paradox seems to be explained by a new concept proposed interpreting the interactions between viscosity factors and blood flow.Facts. – Viscosity factors exert a non linear “all or none” effect that can be described according to the “ percolation theory”. Blood viscosity has no hemodynamic relevance by its own, but viscosity factors (hematocrit, red cell deformability and aggregability, plasma viscosity) can result according to flow conditions in self-potentiating phenomena of quick transition between a state of high fluidity and a state of red cell aggregate clumping. In muscle, this model predicts that: (a) during exercise the only viscosity factor that could influence flow is plasma viscosity; (b) at rest all viscosity factors (including high hematocrit) may induce a self-potentiating “viscidation” process.Conclusion. – According to these concepts, supraphysiologic hematocrit values are probably unable to disturb muscular perfusion at exercise, but are likely to promote self-potentiated stasis at rest and thus to increase the risk of thrombosis. [Copyright &y& Elsevier]

Many studies have already been conducted to better understand blood flow in human vessels. Various techniques, in particular ultrasonic methods such as ultrasonic imaging and Doppler velocimetry have been used. Some microcirculatory disturbances found in human being could be explained by a bad distribution of blood in the capillary network, due to an increase of aggregation and a decrease of deformability of red blood cells (RBC). In the present work, the structure of aggregated RBC suspensions were approached by processing of the ultrasonic backscattering signal using the continuous wavelet transform (CWT) method. Under our experimental conditions, the CWT provides three types of parameters: first, a characteristic time of sedimentation of red blood cells and aggregates, second, characteristic frequencies of fluctuations of the number and density of red blood cells and, third ponderation coefficients of the wavelet transform. Ponderation of the wavelet coefficients was used to calculate the first four statistical moments providing information on the aggregate geometry. Experiences providing from suspensions of normal red blood cells, for various hematocrit from 5% to 35%, aggregated by using dextran 70 (70,000Da) at concentration of 30 g l–1, show that the calculated statistical moments are useful to characterize the size distribution of aggregates. [Copyright &y& Elsevier]

Objectives – The objective of this review is to ascertain information concerning phases of oxygen uptake kinetics and its determinants for constant work rate exercise.Topics – To date, significance of rapid and slow component phases of V˙O2 kinetics is not well understood. Recent studies indicate that initial adaptation of aerobic metabolism represent interplay of factors acting on O2 delivery to mitochondria, enzymatic activity and metabolic inertia within active muscles, rather than an exclusive control system. The mechanism of slow phase is of some debate. But its main origin is concerned with muscle fibre type recruitment.Future prospects – Several models (animal, small muscle mass) have been used to know whether O2 delivery or metabolic inertia set rapid phase. It remains to precise factors which control the different steps from the O2 transfer in ambient air to O2 utilisation for general exercise in humans. Finally, coupling measurement between active muscle V˙O2 and the actual factors determining slow component remains to be determined. [ABSTRACT FROM AUTHOR]

Résumé: Historique: Le syndrome du marteau thénarien est une affection très rare qui peut mimer des maladies rhumatologiques comme le syndrome du canal carpien, le phénomène de Raynaud voire une synovite du poignet ou de la main. Objectif: Décrire la présentation échographique du syndrome du marteau thénarien chez un patient caractéristique. Méthodes: Une échographie en mode B et en doppler couleur pulsé de la main (appareil iU22 Philips) a été réalisée. Résultats: En mode B, il s’agit d’une lésion vasculaire de l’artère radiale perdant ses caractéristiques habituelles et révélant un pseudo-anévrisme avec présence de la formation d’un kyste sacciforme émergeant directement de l’artère adjacente et présentant une paroi d’épaisseur irrégulière avec un flux sanguin turbulent dans la lumière. Le Doppler couleur a montré un flux sanguin dans une partie de la lumière, dont le reste était rempli d’un thrombus apparaissant comme un tissu échogène. Conclusion: L’échographie est une aide diagnostique non invasive du syndrome du marteau thénarien. L’angiographie est facultative chez les patients dont les résultats de Doppler couleur sont typiques. [ABSTRACT FROM AUTHOR]

Moya Moya is a rare disease of uncertain origin, characterised by stenosis of one or both of the internal carotid arteries and responsible of several neurological signs. We present the case of a boy with Moya Moya disease who was scheduled for an epiphisiodesis of the lateral malleola and had a spinal anaesthesia with hyperbaric bupivacaine 0.5% 10 mg without any perioperative complications. Any anaesthetic method could be used, provided special attention is given to avoid changes of capnea and blood pressure to preserve cerebral blood flow and palliate to cerebral flow steal. [Copyright &y& Elsevier]

Aim – Test the hypothesis that increases in forearm blood flow (FBF) during the adaptive phase at the onset of moderate exercise would allow a more rapid increase in muscle oxygen uptake (VO2mus).Materials and methods– Nine subjects completed forearm exercise in control (Ref) and leg occlusion (Occ) conditions. In Occ, exercise of ischemic calf muscles was performed prior to the onset of forearm exercise to activate the muscle chemoreflex evoking a 25 mmHg increase in mean arterial pressure that was sustained during forearm exercise.Results – A higher VO2mus accompanied the higher FBF during the adaptive phase of the Occ tests, yet there was no difference in the baseline or steady state VO2mus between Occ and Ref. Supplying more blood flow at the onset of exercise allowed a more rapid increase in oxidative phosphorylation supporting our hypothesis that, at least for this type of exercise, O2 supply is rate limiting. [Copyright &y& Elsevier]

Coronary microcirculatory is the main target of contrast echocardiography. Coronary flow is one of the parameters which influence the myocardial blood flow but not the only one. Therefore, the knowledge of microcirculatory physiopathology is required in order to analyze datas from contrast echo. [Copyright &y& Elsevier]