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BackgroundAlthough there are robust data about the pathophysiology and prognostic implications of left ventricular (LV) systolic dysfunction in patients with acquired heart disease, similar prognostic data about LV systolic dysfunction are sparse in the tetralogy of Fallot (TOF) population. The purpose of this study was to perform a meta-analysis of all studies that assessed the relationship between LV ejection fraction (LVEF) and cardiovascular adverse events (CAEs) defined as death, aborted sudden death, or sustained ventricular tachycardia.MethodsWe used random-effects models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).ResultsOf the 1,809 citations, 7 studies with 2,854 patients (age 28 ± 4 years) were included. During 5.6 ± 3.4 years' follow-up, there were 82 deaths, 17 aborted sudden cardiac deaths, and 56 sustained ventricular tachycardia events. Overall, CAEs occurred in 5.1% (144 patients). As a continuous variable, LVEF was a predictor of CAE (HR 1.29, 95% CI, 1.09-1.53, P = 0.001) per 5% decrease in LVEF. Similarly, LVEF < 40% was also a predictor of CAE (HR 3.22, 95% CI, 2.16-4.80, P < 0.001).ConclusionsLV systolic dysfunction was an independent predictor of CAE, and we observed a 30% increase in the risk of CAE for every 5% decrease in LVEF, and a 3-fold increase in the risk of CAE in patients with LVEF <40% compared with other patients. These findings underscore the importance of incorporating LV systolic function in clinical risk stratification of patients with TOF and the need to explore new treatment options to address this problem.  相似文献   
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BACKGROUND: Abnormalities in calcium and vitamin D metabolism have been reported after bariatric surgery. The purpose of this study was to evaluate vitamin D nutritional status among morbidly obese patients before gastric bypass surgery. METHODS: We prospectively studied 279 morbidly obese patients seeking gastric bypass surgery for vitamin D nutritional status as assessed by serum 25-hydroxyvitamin D level. In addition, serum samples were analyzed for calcium, alkaline phosphatase (AP), intact parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D. RESULTS: Mean patient age was 43 +/- 9 years; 87% of the study patients were women, and 72% were white. Serum calcium and AP levels were normal in 88% and 89% of the patients, respectively. Vitamin D depletion, defined as serum 25-hydroxyvitamin D level 相似文献   
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The purpose of this study was to provide, in a large number of patients, comprehensive Doppler echocardiographic assessment of normal St Jude Medical mitral valve prosthesis function using Doppler-derived hemodynamic variables, including the mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio and prosthesis performance index. The pressure half-time was less than 130 milliseconds in all patients, and all but one patient had either a peak early mitral diastolic velocity of 2 m/s or less or a mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio of less than 2.2. There was a significant (P < .001) negative correlation between the prosthesis performance index and prosthesis size. This negative correlation suggests that there is more efficient use of the in vitro geometric orifice area with smaller prostheses.  相似文献   
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Event-related brain potentials (ERPs) were recorded during a computerized and modified version of the Digit Span Backwards (DB) task from the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III). The modified DB version (ERP-DB task) was divided into two sections of 2, 4, 6 and 8 digits in length (Group 1) and 3, 5 and 7 digits in length (Group 2). Each trial had a study phase and a test phase. For the study phase, a series of digits was presented sequentially and aurally to 20 participants (10 for each group). For the test phase, a second series of digits was also presented sequentially and aurally that either corresponded to the reverse order of the digits in the study phase (correct condition) or had one digit in the sequence replaced by an incorrect digit (incorrect condition). The traditional DB task of the WAIS-III was also administered for comparison purposes. A prolonged positive slow wave (PSW) peaking between 450 and 750 ms was elicited to incorrect condition trials. For each participant, a derived measure was calculated from the ERP differentiation between correct and incorrect conditions. The derived measure was defined as the mean of the t-values obtained from the correct and incorrect waveform comparison, within the temporal interval that encompassed this component. The strongest statistical correlations between the derived measure and the traditional DB test scores were found at the Pz site (Group 1: r=0.79; Group 2: r=0.59). This statistical approach shows that it is possible to adequately relate an individual's performance on a traditional measure of working memory and ERP patterns. Overall, we believe that this kind of ERP approach holds promise as a technique for assessing quantitatively non-communicative patients.  相似文献   
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AIM: The purpose of this pilot study was to identify the subsurface enamel demineralising potential of two possible acidogenic lactose-based powders and their corresponding generic pump inhalers. METHODS: Ten healthy non-asthmatic adults participated in a 5- leg randomised crossover study including a 10% sucrose control. A twice-daily 400 microg dose of inhaler was applied in vitro to a demineralised enamel slab on the buccal flange of a mandibular removable appliance before in situ placement for 14 days each. Lesion parameters were determined using transverse microradiography and digitised image analysis. RESULTS: Minimal demineralisation occurred with sucrose, both pump and one powder inhaler. The remaining powder was associated with remineralisation (p = 0.29). Overall, mean lesion depth increased (p = 0.12). CONCLUSION: Asthma inhalers failed to demonstrate a significant acidogenic/cariogenic effect.  相似文献   
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