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61.
Heart disease is the leading cause of non-cancer death in childhood cancer survivors. to determine the prevalence of subclinical cardiac dysfunction using speckle tracking and compare its results with those obtained by classical methods of assessing left ventricular function and its relationship with different factors to identify the population at higher risk. Echocardiographic assessment of left ventricular function included ejection fraction, tissue Doppler, longitudinal/circumferential strains and biochemical parameters (troponin-T and Pro-BNP) in a cohort of 57 survivors of childhood acute leukaemia with at least 10 years since diagnosis. Ventricular dysfunction was found in 5.2% of patients in M-mode (ejection fraction—EF?<?53% with a reduction in the EF?≥?10%) and in 7% of patients with Simpson’s method, compared with 21.05 and 8.8% with suboptimal global longitudinal strain (GLS) and global circumferential strain, respectively. The GLS alteration was significantly correlated with lower values of left ventricular systolic function and was associated with high tumour risk (odds ratio [OR] 13.8), cumulative doses of anthracyclines?≥?250 mg/m2 (OR 7.6) and radiotherapy (OR 7.19). Biomarkers were not useful for the diagnosis of subclinical cardiomyopathy. Good reproducibility was obtained, with an intraobserver correlation of 93.6% and an interobserver correlation of 89.2% in the GLS. The alteration of the GLS was more prevalent than the alteration in the EF and was associated with the treatment received and high tumour risk. strain imaging seems to be a powerful tool to identify an increased number of survivor with an early myocardial injury.  相似文献   
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BackgroundSevere aortic stenosis (AoS) is considered a primary cause of syncope. However, other mechanisms may be present in these patients and accurate diagnosis can have important clinical implications. The aim of this study is to assess the different etiologies of syncope in patients with severe AoS and the impact on prognosis of attaining a certain or highly probable diagnosis for the syncope.MethodsOut of a cohort of 331 patients with AoS and syncope, 61 had severe AoS and were included in the study. Main cause of syncope and adverse cardiac events were assessed.ResultsIn 40 patients (65.6%), we reached a certain or highly probable diagnosis of the main cause of the syncope. AoS was considered the primary cause of the syncope in only 7 patients (17.5% of the patients with known etiology). Atrioventricular block (14 patients, 35.0%) and vasovagal syncope (6 patients, 15.0%) were the most frequently diagnosed causes. The presence of a known cause for syncope during the admission was not associated with a lower incidence of recurrence during follow-up (hazard ratio [HR] 0.69, 95% confidence interval [CI] 0.20-2.40). Syncope of unknown etiology was independently associated with greater mortality during 1-year follow-up (HR 5.4, 95% CI 1.3-21.6) and 3-year follow-up (HR 3.5, 95% CI 1.2-10.3).ConclusionsIn a high proportion of patients with severe AoS admitted for syncope, the valvulopathy was not the main cause of the syncope. Syncope in two-thirds of this population was caused by either bradyarrhythmia or reflex causes. Syncope of unknown cause was associated with increased short- and medium-term mortality, independently from treatment of the valve disease. An exhaustive work-up should be conducted to determine the main cause for syncope.  相似文献   
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CardioVascular and Interventional Radiology - Yttrium-90 radioembolization (RE) is a widely used transcatheter intraarterial therapy for patients with unresectable liver cancer. In the last decade,...  相似文献   
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BACKGROUND: Changes in circadian variation of blood pressure (BP) could be used either to predict preeclampsia or to assess its severity. We examined and compared characteristics of circadian variability in BP in women with both healthy and complicated pregnancies who were systematically monitored throughout gestation. METHODS: We analyzed 2430 BP series sampled by ambulatory monitoring for 48 h once every 4 weeks from the first obstetric visit until delivery in 235 women with uncomplicated pregnancies, 128 with gestational hypertension, and 40 with preeclampsia. The circadian pattern of BP variation for each group and trimester of gestation was established by population multiple-components analysis. RESULTS: The differences in 24-h mean and amplitude between healthy and complicated pregnancies were highly significant in all trimesters (P < 0.001). Results further indicated similar circadian characteristics between gestational hypertension and preeclampsia in the first trimester of pregnancy. The difference between these two groups in 24-h mean was statistically significant for systolic (P =.002) and diastolic BP (P =.038) in the second trimester and, to a larger extent, in the third trimester (P < 0.001). CONCLUSIONS: The differences in BP between healthy and complicated pregnancies that can be observed as early as in the first trimester of pregnancy are found when both systolic and diastolic BP for women with a later diagnosis of gestational hypertension or preeclampsia are well within the accepted range of normotension. These differences offer new end points that may lead to an early identification of hypertensive complications in pregnancy as well as to the establishment of prophylactic intervention.  相似文献   
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This article reviews the most significant developments reported between July 2006 and July 2007 in the fields of pediatric cardiology and congenital heart disease, in diagnosis and treatment in particular. In the area of imaging techniques, the increasing clinical roles of magnetic resonance imaging, tissue Doppler imaging and three-dimensional echocardiography are highlighted, as is the application of these techniques to fetal cardiology and its repercussions. The incidence and treatment of arrhythmias in children are also discussed and, with regard to heart failure, there is an assessment of recent findings in epidemiology and diagnosis, new drugs, ventricular assist systems, and the current status of heart transplantation. In the area of interventional cardiology, present-day techniques for the closure of atrial and ventricular septal defects are reviewed and there is an assessment of early results with partially absorbable devices, percutaneous pulmonary valve implantation, and new types of stent (e.g., premounted, coated and absorbable stents). In cardiac surgery, the focus is on studies that evaluate outcome quality, the search for new biocompatible conduits, experience with new techniques for treating complex transpositions (e.g., the Nikaidoh procedure and its variants), the medium- and long-term results of treating aortic valvular disease with pulmonary autografts (i.e., the Ross and Ross-Konno procedures), and current findings on the treatment of pulmonary insufficiency after correction of either the tetralogy of Fallot or a dysfunctional Fontan circuit.  相似文献   
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Territorial aggression, exhibited by male vertebrates in a reproductive context, is generally thought to be mediated by elevated levels of the gonadal steroid hormone testosterone. Rufous-collared sparrows from Papallacta, Ecuador are only aggressive during the breeding season when plasma testosterone concentrations are elevated. However, previous experiments have determined that during the breeding season testosterone does not increase in response to territorial challenges and testosterone implants do not make males more aggressive. This relationship between testosterone and aggression is different from closely related northern latitude species. We conducted another experiment investigating the role of testosterone in mediating territorial aggression, during the breeding season, in male rufous-collared sparrows. We predicted that blocking the actions of the testosterone would suppress aggression in response to territorial challenges. During the early breeding season males were captured using a simulated territorial intrusion and there was no relationship between time to capture and plasma testosterone, dihydrotestosterone, and corticosterone concentrations. Individual males were then implanted with both the aromatase inhibitor ATD and the anti-androgen Flutamide or empty implants as a control. After one week, birds were challenged with a simulated territorial intrusion and the aggressive responses measured. There were no differences in individual behavioral responses (number of songs, flights, closest approach, or time within 5 m) or overall aggression between the two groups. Androgen levels were elevated, post-implant, in the experimental group suggesting that the treatment was successful by blocking the negative feedback system. We conclude that pharmacologically inhibiting testosterone during the breeding season does not affect territorial aggression in these birds.  相似文献   
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Prothrombin A19911G and G20210A polymorphisms' role in thrombosis   总被引:9,自引:0,他引:9  
The prothrombin G20210A polymorphism, which correlates with the plasmatic prothombin levels, is the second genetic risk factor for deep venous thrombosis (DVT), although its prothrombotic role is mild. Recently, the prothrombin A19911G polymorphism, also associated with slight variations of the prothrombin level, has been suggested to modulate the thrombotic risk of the G20210A polymorphism in a preliminary study including few patients and controls. Our study evaluated the effect of the A19911G polymorphism in the arterial and venous thrombotic risk of the prothrombin 20210G/A genotype, analysing 204 consecutive DVT patients and 204 matched controls. Moreover, we analysed 213 carriers of the 20210G/A genotype (152 with DVT, 26 with arterial thrombosis and 35 healthy subjects) and 10 homozygous 20210 A/A carriers. We developed a simple method to simultaneously determine the genotype of both polymorphisms. In accordance with our case/control study, the A19911G polymorphism did not play a significant role in the development of DVT. Analysis of 120 20210 A alleles demonstrated a complete linkage disequilibrium with the 19911 A allele. These polymorphisms (alone or combined) did not modify the risk of arterial thrombosis. However, the 19911A/G genotype slightly increased the risk of developing DVT in carriers of the 20210G/A genotype (OR 3.34 vs 5.86), supporting that the prothrombin 19911 polymorphism could modulate the risk of the G20210A polymorphism in developing DVT.  相似文献   
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