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Pulmonary hypertension (PH) is a heterogeneous condition. To date, no registry data exists reflecting the spectrum of disease across the five diagnostic groups encountered in a specialist referral centre. Data was retrieved for consecutive, treatment-na?ve cases diagnosed between 2001 and 2010 using a catheter-based approach. 1,344 patients were enrolled, with a mean follow-up of 2.9 yrs. The 3-yr survival was 68% for pulmonary arterial hypertension (PAH), 73% for PH associated with left heart disease, 44% for PH associated with lung disease (PH-lung), 71% for chronic thromboembolic PH (CTEPH) and 59% for miscellaneous PH. Compared with PAH, survival was inferior in PH-lung and superior in CTEPH (p<0.05). Multivariate analysis demonstrated that diagnostic group independently predicted survival. Within PAH, Eisenmenger's survival was superior to idiopathic PAH, which was superior to PAH associated with systemic sclerosis (p<0.005). Within PH-lung, 3-yr survival in sleep disorders/alveolar hypoventilation (90%) was superior to PH-lung with chronic obstructive pulmonary disease (41%) and interstitial lung disease (16%) (p<0.05). In CTEPH, long-term survival was best in patients with surgically accessible disease undergoing pulmonary endarterectomy. In this large registry of consecutive, treatment-na?ve patients identified at a specialist PH centre, outcomes and characteristics differed between and within PH groups. The current system of classification of PH has prognostic value even when adjusted for age and disease severity, emphasising the importance of systematic evaluation and precise classification.  相似文献   
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Kinetics of Atrial Repolarization Alternans. Introduction: Repolarization alternans (Re‐ALT), a beat‐to‐beat alternation in action potential repolarization, promotes dispersion of repolarization, wavebreaks, and reentry. Recently, Re‐ALT has been shown to play an important role in the transition from rapid pacing to atrial fibrillation (AF) in humans. The detailed kinetics of atrial Re‐ALT, however, has not been reported so far. We developed a chronic free‐behaving ovine pacing model to study the kinetics of atrial Re‐ALT as a function of pacing rate. Methods: Thirteen sheep were chronically implanted with 2 pacemakers for the recording of broadband right atrial unipolar electrograms and delivery of rapid pacing protocols. Beat‐to‐beat differences in the atrial T‐wave apex amplitude as a measure of Re‐ALT and activation time were analyzed at incremental pacing rates until the effective refractory period (ERP) defined as stable 2:1 capture. Results: Atrial Re‐ALT appeared intermittently but without periodicity, and increased in amplitude as a function of pacing rate until ERP. Intermittent 2:1 atrial capture was observed at pacing cycle lengths 40 ms above ERP, and increased in duration as a function of pacing rate. Episodes of rapid pacing‐induced AF were rare, and were preceded by Re‐ALT or complex oscillations of atrial repolarization, but without intermittent capture. Conclusion: We show in vivo that atrial Re‐ALT developed and increased in magnitude with rate until stable 2:1 capture. In rare instances where capture failure did not occur, Re‐ALT and complex oscillations of repolarization surged and preceded AF initiation. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1003‐1012, September 2012)  相似文献   
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Objective. To assess the inter-rater reliability of the BILAG2004-Pregnancy index for assessment of SLE disease activity in pregnancy. Methods. Pregnant SLE patients were recruited from four centres and assessed separately by two raters/physicians in routine clinical practice. Disease activity was determined using the BILAG2004-Pregnancy index. Reliability was assessed using level of agreement, κ-statistics and analysis of disagreement. Major disagreement was defined as a score difference of A and C/D/E or B and D/E between the two raters, and minor disagreement was a score difference of A and B or B and C between raters. Results. A total of 30 patients (63.3% Caucasian, 13.3% Afro-Caribbean, 16.7% South Asian) were recruited. The majority of patients had low-level disease activity according to the local rater's assessment, and there was no grade A activity, with grade B activity present in the following systems: mucocutaneous (nine patients), musculoskeletal (two patients), cardiorespiratory (one patient) and renal (one patient). The distribution of disease activity was similar to the external rater's assessment. Good levels of agreement (>70%) were achieved in all systems. κ-statistics were not appropriate for use in the gastrointestinal, ophthalmic, constitutional and neuropsychiatric systems, as there was minimal variation between patients but good levels of agreement otherwise. There were three major disagreements (0.1 per patient, all differences between B and D/E) and five minor disagreements (0.17 per patient). Conclusion. The BILAG2004-Pregnancy index is reliable for assessment of disease activity in pregnant SLE patients.  相似文献   
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Purpose:National Accreditation Board for Hospitals and Healthcare Providers operates the health-care accreditation program in India. Research on impact of accreditation on eye-care centers is scarce. This article was conceptualized to scientifically evaluate the changes in documentation brought about by accreditation and its effects on staff in the Ophthalmology Department of an Indian Medical College.Methods:This was conducted as a quasi-experimental study in four steps. First, a point-based evaluation of case sheets in both pre-accreditation and postaccreditation phase, along with statistical analysis of the results, was done. Step two involved analysis of quality indicators and patient safety indices in successive years from inception of data to post-accreditation phase. Step three comprised a survey of staff employing a validated tool, and finally, face-to-face semistructured interviews with designated authorities, including finance departmental head, completed the study.Results:A statistically significant difference was seen in scores achieved by the pre and postaccreditation case sheets, with the postphase case sheets achieving 15% increased scores over the prephase case sheets. Quality indicator indices displayed improvements post-accreditation. There was an accompanying increase in quantity of documentation. Financial data analysis showed increased expenditure for accreditation under multiple heads. Staff believed that accreditation led to increased workload but did not express decreased satisfaction and felt that accreditation was eventually beneficial. However, staff believed rewards for improving quality can be enhanced.Conclusion:Accreditation increases quality and quantity of documentation, and staff workload. Increased financial costs also ensue.Staff believe that accreditation improves quality, is beneficial, but desire enhanced rewards.  相似文献   
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Although accounting for 90 % of the intestinal surface area, small bowel adenocarcinomas are not common. The majority of these lesions are incidentally detected during laparotomy for intestinal obstruction or perforation. The symptoms associated with these lesions are not very specific and preoperative diagnosis is rare. We report two cases of jejunal adenocarcinomas detected in patients undergoing laparotomy for acute abdomen and review the literature for small bowel adenocarcinomas.  相似文献   
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