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Cardiac resynchronization therapy (CRT) is a treatment option in patients with severe heart failure and left bundle-branch block (LBBB). This study evaluated the effects of 4 and 13 mo of CRT on myocardial oxygen consumption (MVO2) and cardiac efficiency as compared with mild heart failure patients without LBBB. METHODS: Sixteen patients with severe heart failure and LBBB due to idiopathic cardiomyopathy were studied at baseline and after 4 and after 13 mo of therapy. Thirteen patients with mild heart failure without LBBB served as a comparison group. The clearance rate (k2) of 11C-acetate was measured with PET to assess MVO2. Stroke volume was derived from the dynamic PET data according to the Stewart-Hamilton principle and, furthermore, cardiac efficiency using the work metabolic index. RESULTS: After 4 mo of CRT, stroke volume index (SVI) increased by 50% (P = 0.012) and cardiac efficiency increased by 41% (P < 0.001). Global k2 remained unchanged but regional k2 demonstrated a more homogeneous distribution pattern. The parameters showed no significant changes during therapy. Under CRT, cardiac efficiency, SVI, and the distribution pattern of regional k2 did not differ from mild heart failure patients without LBBB. CONCLUSION: CRT improves cardiac efficiency for at least 13 mo, as demonstrated by a higher SVI, whereas MVO2 remains unchanged. Cardiac efficiency, SVI, and the MVO2 distribution pattern reach the level of patients with mild heart failure without LBBB. The unfavorable hemodynamic performance in heart failure with LBBB is effectively restored by long-term CRT to the level of an earlier disease state.  相似文献   
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In this paper, we describe the phenotypic and molecular characteristics of two clinically relevant, vancomycin-resistant (VanB), linezolid-resistant Enterococcus faecium isolates. Pyrosequencingtrade mark showed the G to T single nucleotide polymorphism at bp 2576 in the genes coding for 23S rRNA and was used to quantify the proportion of G to T mutations among six different 23S rRNA genes in E. faecium as a marker for the molecular level of resistance to linezolid. In both isolates, the G to T mutation was found in two of six alleles, and no further mutations in the genes coding for 23S rRNA were found. The dynamic process of linezolid resistance could be demonstrated by the complete reversion of resistant alleles back to only wild type alleles in consecutive isolates of one isolate. Pyrosequencingtrade mark being used to detect and quantify resistance to linezolid has been proven as a fast and reliable molecular screening method for monitoring linezolid resistance.  相似文献   
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Prosthetic valve thrombosis (PVT) is a life-threatening disease, for which treatment strategies have been controversial. Herein, existing data on management options are reviewed, and conclusions drawn as to the choice and use of treatment strategies for PVT. The use of transesophageal echocardiography (TEE) allows distinction to be made between obstructive and non-obstructive PVT by the presence or absence of occluder motion limitation. The differentiation of PVT from pannus and vegetation is, however, still limited by TEE. The incidence of PVT has been underestimated by not taking into account a large percentage of non-obstructive PVT. Although the standard treatment for PVT has been surgery, thrombolysis has lower mortality rates, particularly in patients in NYHA functional classes III-IV. The lowest complication rates with thrombolysis have been achieved in patients with non-obstructive PVT. Pregnancy, left atrial appendage thrombi and large PVT are not contraindications to thrombolysis. The third therapeutic option is anticoagulant therapy. The detrimental effect of anticoagulant treatment in obstructive PVT was shown in a prospective study. Non-obstructive thrombi of > 5 mm length have been treated with higher success rates and lower complication rates by thrombolysis than by anticoagulant treatment. In conclusion, all patients with suspected PVT should undergo multiplane TEE. Thrombolysis is the first-line treatment for obstructive PVT, independent of NYHA class and thrombus size if there are no contraindications. Serial TEE studies must be conducted during thrombolysis. Surgery should be reserved for those patients in whom thrombolysis is contraindicated, or has failed. Initial anticoagulant therapy is recommended only for small, non-obstructive PVT if anticoagulation had been subtherapeutic; otherwise, thrombolysis is the treatment of choice if there are no contraindications.  相似文献   
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Major reasons for the considerable heterogeneity among published results of heart valve surgery are inconsistency in follow up techniques, reporting systems and classification of adverse events. The present recommendations are intended to harmonize the presentation of clinical material in order to improve comparison of data from different sources for the analysis of pooled data. The quality of an observational study is largely, if not entirely, due to the follow up technique, which may be graded according to six categories: Self-reporting of adverse events/well-being by the patients may be classified 'excellent'; if the information is gathered and re-checked at short-term intervals. Data obtained from in-hospital or outpatient examinations by qualified examiners at least twice a year or other personal contact through qualified examiners may be regarded as 'sufficient', if the results are re-checked by contacting the treating home physician. All other follow up techniques may be regarded as inappropriate. Consequences of complications are entirely dependent on severity and possible sequelae. It is therefore recommended to grade any reported complication according to its severity by utilizing a score system. Embolisms are best categorized by utilizing the performance status scale. Bleeding events may be categorized according to severity as fatal, major (requiring hospital transmission with transfusion, surgery or with permanently increased disability) or minor (not requiring hospital admission, surgery or transfusion). In some cases it will remain unclear whether an event was primarily embolic or hemorrhagic. These complications should be summarized as 'not categorized'. The reporting of morbid events due to thrombosis, embolism and bleeding should go along with information regarding the quality of antithrombotic management.  相似文献   
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