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21.
A case of a 51 year old patient with a history of myocardial infarction (MI) and recurrent ventricular tachycardia (VT) is presented. Three months after MI the patient underwent coronary angioplasty and one year later received prophylactic implantable cardioverter-defibrillator (ICD) due to complex ventricular arrhythmias, detected on Holter ECG monitoring, and depressed left ventricular ejection fraction. Later on the patient started to experience palpitations and ICD shocks during physical activity (cycling). Interrogation of the ICD memory showed appropriate shocks due to slow (160 betas/min) VT. The device was reprogrammed and new antitachycardia pacing (ATP) algorithms were enabled, however, it occurred proarrhythmic due to the ATP-induced acceleration of VT rate. Finally, in April 2005 he received 37 appropriate ICD shocks during a few hours. The patient was selected for RF ablation and underwent successful procedure with the use of the electro-anatomical CARTO mapping system.  相似文献   
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The hypothalamic–pituitary–adrenal (HPA) axis displays a characteristic circadian pattern of corticosterone release, with higher levels at the onset of the active phase and lower levels at the onset of the inactive phase. As corticosterone levels modify the response to stress and influence the susceptibility to and/or severity of stress-related sequelae, we examined the effects of an acute psychological trauma applied at different zeitgeber times (ZTs) on behavioral stress responses. Rats were exposed to stress either at the onset of the inactive-(light) phase (ZT=0) or at the onset of the active-(dark) phase (ZT=12). Their behavior in the elevated plus-maze and acoustic startle response paradigms were assessed 7 days post exposure for retrospective classification into behavioral response groups. Serum corticosterone levels and the dexamethasone suppression test were used to assess the stress response and feedback inhibition of the HPA axis. Immunoreactivity for neuropeptide Y (NPY) and NPY-Y1 receptor (Y1R) in the paraventricular (PVN) and arcuate (ARC) hypothalamic nuclei, hippocampus, and basolateral amygdala were measured. The behavioral effects of NPY/Y1R antagonist microinfused into the PVN 30 min before stress exposure during the inactive or active phase, respectively, were evaluated. PVN immunoreactivity for NPY and Y1R was measured 1 day after the behavioral tests. The time of day of the traumatic exposure markedly affected the pattern of the behavioral stress response and the prevalence of rats showing an extreme behavioral response. Rats exposed to the stressor at the onset of their inactive phase displayed a more traumatic behavioral response, faster post-exposure corticosterone decay, and a more pronounced stress-induced decline in NPY and Y1R expression in the PVN and arcuate hypothalamic nuclei. Blocking PVN Y1R before stress applied in the active phase, or administering NPY to the PVN before stress applied in the inactive phase, had a resounding behavioral effect. The time at which stress occurred significantly affected the behavioral stress response. Diurnal variations in HPA and NPY/Y1R significantly affect the behavioral response, conferring more resilience at the onset of the active phase and more vulnerability at the onset of the inactive phase, implying that NPY has a significant role in conferring resilience to stress-related psychopathology.  相似文献   
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BackgroundRadial artery access has been shown to reduce mortality and bleeding events, especially in patients with acute coronary syndromes. Despite this, interventional cardiologists experienced in femoral artery access still prefer that route for percutaneous coronary intervention. Little is known regarding the merits of each vascular access in patients stratified by their risk of bleeding.MethodsPatients from the Global Leaders trial were dichotomized into low or high risk of bleeding by the median of the PRECISE-DAPT score. Clinical outcomes were compared at 30 days.ResultsIn the overall population, there were no statistical differences between radial and femoral access in the rate of the primary end point, a composite of all-cause mortality, or new Q-wave myocardial infarction (MI) (hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.42-1.15). Radial access was associated with a significantly lower rate of the secondary safety end point, Bleeding Academic Research Consortium (BARC) 3 or 5 bleeding (HR 0.55, 95% CI 0.36-0.84). Compared by bleeding risk strata, in the high bleeding score population, the primary (HR 0.47, 95% CI 0.26-0.85; P = 0.012; Pinteraction = 0.019) and secondary safety (HR 0.57, 95% CI 0.35-0.95; P = 0.030; Pinteraction = 0.631) end points favoured radial access. In the low bleeding score population, however, the differences in the primary and secondary safety end points between radial and femoral artery access were no longer statistically significant.ConclusionsOur findings suggest that the outcomes of mortality or new Q-wave MI and BARC 3 or 5 bleeding favour radial access in patients with a high, but not those with a low, risk of bleeding. Because this was not a primary analysis, it should be considered hypothesis generating.  相似文献   
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BACKGROUND: Modern therapy of acute myocardial infarction (AMI) is aimed at rapid and persisting restoration of blood flow in an infarct-related artery (IRA). However, in some patients myocardial reperfusion is not achieved in spite of effective IRA recanalisation. Myocardial Blush Grade (MBG) is one of the angiographic markers useful for the detection of this phenomenon. AIM: To assess the prognostic value of MBG in patients with anterior AMI treated with primary angioplasty. METHODS: The study group consisted of 104 patients (74 males, 30 females, mean age 62+/-13 years) treated with primary angioplasty due to anterior ST-segment elevation AMI. MBG was assessed after the procedure. The mortality and major cardiovascular event (MACE) rates were analysed one and six months after AMI. RESULTS: Patients with preserved myocardial reperfusion following angioplasty (MBG 2-3, n=64 (61.5%)) had a trend towards lower one-month mortality and significantly reduced six-month mortality compared with 40 (38.5%) patients with an impaired (MBG 0-1) myocardial reperfusion (3% vs 12.5%, NS; and 6.25% vs 20%, p<0.05, respectively). The rate of MACE was significantly lower in patients with rather than without reperfusion both after one and six months of follow-up (9.4% vs 27.5%, p=0.027 and 12.5% vs 42.5%, p<0.001, respectively). Compared with patients with a high MBG score, patients with altered reperfusion more frequently had diabetes (30% vs 12.5%, p=0.04), hypertension (67.5% vs 45%, p=0.043), longer time from the onset of symptoms to balloon inflation (355.9+/-199 min vs 215.5+/-113 min, p<0.001) and lower left ventricular ejection fraction, measured 3 days after AMI (43.3%+/-8 vs 47.4%+/-9, p=0.02). CONCLUSIONS: MBG has a significant prognostic value in patients with anterior AMI treated with primary angioplasty. Diabetes, hypertension and long delay of treatment are associated with the impairment of myocardial reperfusion.  相似文献   
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Thrombophilia, the state of increased tendency for blood clotting, is considered the disorder of a complex etiology, caused by both environmental and genetic factors. As gene variants predisposing to thrombophilia and influencing the increased risk of vein thrombosis might influence response to local thrombolysis, the aim of the work was to characterize the pharmacogenetic conditions for local streptokinase treatment in patients with a deep vein thrombosis (DVT) of lower extremities based on the following polymorphism analyses: G1691A polymorphism of factor V (FV), G20210A polymorphism of prothrombin (PT), A4250G (Thr312Ala) polymorphism of fibrinogen-alpha (FGA), G(-455)A polymorphism of fibrinogen-beta (FGB), 4G/5G polymorphism of plasminogen activator inhibitor type 1(PAI-1) and insertion/deletion (I/D) polymorphism of tissue plasminogen activator (t-PA). The study included 40 DVT patients who underwent a local thrombolytic treatment within 14-day period from diagnosis. Full recanalization was achieved in 20 subjects (50%) [group R(+)], whereas incomplete or total lack of recanalization was identified in the remaining 20 patients [group R(-)]. No major complications of thrombolytic treatment occurred in the studied group. In the case of prothrombin gene all individuals carried homozygous wild type genotype (GG). Prevalence of the genotypes and alleles of the remaining five polymorphisms did not differ significantly between the groups R(+) and R(-). Neither sex nor age, smoking or time period from diagnosis to introduction of the thrombolytic treatment significantly influenced treatment efficacy. The results of the study suggest that a local thrombolysis with streptokinase introduced within two week period from the diagnosis is a safe and efficient method of treatment for deep vein thrombosis of lower extremities. However, size of the group is insufficient to clearly determine the association between investigated polymorphisms and efficacy of local treatment with streptokinase.  相似文献   
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Hepatocellular carcinoma is the main liver-related cause of death in patients with compensated cirrhosis. The early phases are asymptomatic and the prognosis is poor, which makes prevention essential. We propose that non-selective beta-blockers decrease the incidence and growth of hepatocellular carcinoma via a reduction of the inflammatory load from the gut to the liver and inhibition of angiogenesis.  相似文献   
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