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51.
BACKGROUND AND AIM OF THE STUDY: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia encountered in clinical practice. In developing countries, rheumatic mitral stenosis (MS) is the most frequent underlying condition in patients with AF. Sinus rhythm (SR) is difficult to achieve and maintain in these patients, but would be more easily achieved with reduction of left atrial pressure after successful balloon mitral valvotomy (BMV). METHODS: Eighty-five patients with persistent AF following BMV received amiodarone (600 mg once daily for two weeks, 200 mg daily thereafter). Electrical cardioversion was performed in those with persistent AF (at six and 12 weeks of drug therapy). RESULTS: Among patients, 33 (39%) converted with amiodarone alone. Of 52 patients who underwent cardioversion at six weeks, 41 (79%) converted to SR. Overall, 87% of patients converted to SR. None of the 11 patients with persistent AF could be converted to SR, despite a second attempt with direct current (DC) cardioversion at 12 weeks. Those who converted to SR had significantly shorter AF duration (AFD) (2.7+/-1.1 versus 3.2+/-0.7 years) and smaller left atrial (LA) size (50.0+/-7.7 versus 57.9+/-4.7 mm). Patient age, gender, NYHA class, ejection fraction and post-BMV variables were comparable between the two groups. Successful maintenance of SR was possible in 61/74 (82%) patients at a mean follow up of 30.6+/-7.1 months (range: 16-43 months). Again, mean AFD was shorter (1.8+/-0.6 versus 3.0+/-0.7 years) and LA size smaller (48.9+/-7.5 versus 54.7+/-6.9 mm) among those who maintained SR. However, even in patients with AFD > or =2 years, successful conversion and maintenance of SR was possible in 74% and 62% of patients, respectively. Among patients with LA size > or =60 mm (n = 16), the corresponding value were 84% and 77%, respectively. On multivariate analysis, only AFD was a predictor of acute and long-term success. The probability of SR remaining in those with AFD <2 years at 21, 30 and 43 months was 96%, 95% and 94.6%, respectively, while for those with AFD > or =2 years these values were 62%, 48% and 40%. CONCLUSION: Low-dose amiodarone was safe and effective in restoring and maintaining SR in patients with AF and rheumatic heart disease.  相似文献   
52.
BACKGROUND & AIMS: Organ failure is the usual cause of death in acute necrotizing pancreatitis. Our objective was to study whether the extent and infection of pancreatic necrosis correlate with organ failure and mortality. METHODS: All consecutive patients with acute pancreatitis were prospectively studied. They underwent a detailed clinical and investigative evaluation. Pancreatic necrosis, diagnosed on a computed tomography scan, was graded as <30%, 30%-50%, and >50% necrosis and characterized as either sterile or infected. Logistic regression analysis was done to find out the association of the extent and infection of pancreatic necrosis with organ failure and mortality. RESULTS: Of 276 patients (mean age, 41.25 years; 172 men), 104 had pancreatic necrosis: 30 had <30% necrosis, 37 had 30%-50% necrosis, and 37 had >50% necrosis; 74 had sterile necrosis, and 30 had infected necrosis. Of them, 37 (35%) patients developed organ failure. Two significant factors were associated with the development of organ failure, the extent of necrosis (<30% necrosis vs 30%-50% necrosis: P = .03; odds ratio [OR], 5.82; 95% confidence interval [CI], 1.15-29.45; <30% necrosis vs >50% necrosis: P = .0004; OR, 18.86; 95% CI, 3.75-94.92) and infected pancreatic necrosis (P = .02; OR, 3.29; 95% CI, 1.17-9.24). The overall mortality was 22%. Infected pancreatic necrosis (P = .006; OR, 4.99; 95% CI, 1.56-16.02) and Acute Physiology, Age, and Chronic Healthy Evaluation II score (P = .004; OR, 1.28; 95% CI, 1.08-1.52) were 2 independent predictors of mortality. CONCLUSIONS: Extent of necrosis and infected pancreatic necrosis were associated with the development of organ failure in patients with acute necrotizing pancreatitis. Infected pancreatic necrosis was the most significant predictor of mortality.  相似文献   
53.
Positron emission tomography (PET) has been promoted as a means of improving the diagnosis of Alzheimer's disease (AD), but the evidence to support its incremental value is unclear. To assess the evidence regarding the use of PET in the clinical evaluation of AD, a systematic review of the English-language literature indexed in MEDLINE (1975-January 2001), the Cochrane Library (issue 4, 2000), and health technology assessment (HTA) reports was conducted. Articles identified by this review process were graded for methodological and reporting quality using a standardized grading scheme. Sixteen original articles and seven HTA reports were identified. In general, the articles addressed: using PET to differentiate AD from normal aging or non-Alzheimer's dementias, PET imaging compared with single positron emission computed tomography imaging, using PET to predict the progression of dementia, and agreement and reliability in the interpretation of PET images. Serious problems with study design and methodology in all articles were identified. Previous HTA reports have generally recommended that PET not be used in the clinical evaluation of dementia. In conclusion, there is little evidence to support the addition of PET to the routine clinical evaluation of patients with suspected or established dementia. Suggestions for future research in this area are offered.  相似文献   
54.
Gastric tuberculosis is rare and usually presents as an ulcerated lesion or gastric outlet obstruction. Rarer presentations include massive gastrointestinal bleed and gastric perforation. A case of gastric tuberculosis presenting as linitis plastica is reported here. This is the first such case report. The patient was a young woman who presented with non-specific abdominal pain and significant weight loss. The gastric mucosa appeared oedematous and hyperaemic and there was spontaneous oozing of blood on upper gastrointestinal endoscopy. Computed tomography of the abdomen revealed diffuse thickening of the gastric wall. The diagnosis was confirmed by the presence of caseating granulomas with acid fast bacilli in the endoscopic biopsy specimen. The patient showed significant clinical improvement on four-drug anti-tuberculous treatment.  相似文献   
55.
Pain is the most distressing symptom of chronic pancreatitis. Although the pathogenesis of pain is still poorly understood, an increase in intraductal pressure may be the dominant factor. The management of pain can involve medical, endoscopic, neurolytic, and surgical therapies. Endotherapy includes pancreatic sphincterotomy, extraction of stones, placement of stent, and dilatation of strictures, sometimes preceded or followed by extracorporeal shock‐wave lithotripsy. Several studies have now shown that endotherapy provides partial or complete relief of pancreatic pain in a majority of patients with an acceptable frequency of early and late complications. Endotherapy should now graduate from an experimental form of treatment to a realistic treatment option in patients with chronic or relapsing pain, particularly in the setting of calcific chronic pancreatitis.  相似文献   
56.
OBJECTIVE: To evaluate the dose-related benefit of angiotensin-converting enzyme (ACE) inhibitor therapy among older adults with heart failure and to evaluate whether low-dose ACE inhibitor therapy is better than none. DESIGN: Observational cohort study. SETTING: Community-dwelling older adults in Ontario, Canada. PATIENTS/PARTICIPANTS: We identified 16539 adults 66 years or older who survived 45 days following their first heart failure hospitalization discharge. MEASUREMENT AND MAIN RESULTS: Multivariate techniques including propensity scores were used to study the association between the dose of ACE inhibitor therapy dispensed and 3 outcomes: survival, survival or heart failure rehospitalization, and survival or all-cause hospitalization at 1 year of follow-up. Logistic regression models explored the association between initial dose dispensed and subsequent dose reduction or drug cessation. Overall, 10793 (65.3%) of patients were dispensed ACE inhibitor therapy, with more than a third (3935; 36.5%) initiated on low-dose therapy. Relative to dispensing of low-dose ACE inhibitor therapy, nonuse was associated with increased mortality (hazard ratio [HR], 1.12; 95% confidence interval [CI], 1.02 to 1.22). Dispensing medium-dose therapy provided a benefit similar to low-dose (HR, 0.94; CI, 0.86 to 1.03) and dispensing of high-dose therapy was associated with improved survival benefit (HR, 0.76; CI, 0.68 to 0.85). Relative to dispensing of low-dose ACE inhibitor therapy, dispensing high-dose conferred a benefit (HR, 0.87; CI, 0.80 to 0.95) on the composite outcome of 1-year mortality or heart failure hospitalization and the composite outcome of 1-year mortality or all-cause hospitalization (HR, 0.87; CI, 0.81 to 0.93). Relative to those dispensed low-dose ACE inhibitor therapy, those initially dispensed high-dose therapy were twice as likely to have their subsequent dose reduced or the therapy discontinued (odds ratio, 2.36; CI, 2.07 to 2.69). CONCLUSION: Our findings suggest that when possible, older adults should be titrated to the higher doses of ACE inhibitor therapy evaluated in clinical trials. If older adults cannot tolerate higher doses, then low-dose ACE inhibitor therapy is superior to none. High-dose ACE inhibitor therapy is not as well tolerated as lower doses.  相似文献   
57.
Liver involvement in tuberculosis in absence of miliary tuberculosis is rare. This study was performed to analyse the spectrum and response to treatment of hepatic tuberculosis in the absence of miliary abdominal tuberculosis. Retrospective analysis of seven cases of hepatic tuberculosis without miliary abdominal tuberculosis who presented at the single tertiary referral center were analyzed. All patients presented with fever and hepatomegaly. Five of them had pain in upper abdomen and vomiting. HIV serology was positive in one patient. All patients had normocytic normochromic anaemia, raised erythrocyte sedimentation rate (Mean 65). Mild elevation of liver enzymes and low albumin (Mean 2.4 gm%) with reversal of albumin globulin ratio (Mean 0.6) were seen in all. Two had jaundice. Prothrombin time was normal in all and lactate dehydrogenase values were elevated in all (Mean 794 IU/L). On ultrasonography, 2 had multiple hypodense lesion, 1 had coarse echotexture of liver, 1 had hyperechoic pattern and 3 had just hepatomegaly. Complete resolution of liver lesions on treatment with 4-drug anti-tuberculosis drug chemotherapy was seen. In conclusion, liver tuberculosis has protean manifestations with nonspecific alteration of liver function tests and is best diagnosed on liver biopsy. Overall response to therapy is satisfactory.  相似文献   
58.
59.
Many important therapeutic lessons have been learned since the discovery of hepatitis C virus (HCV) in 1989. A sustained virological response (SVR) is now recognized to be considered tantamount to a cure and is the goal of therapy for chronic hepatitis C (CHC). Prior to the development of directly-acting antiviral therapies (DAA), SVR rates of between 50?% and 80?% were achievable using the previous standard of care for CHC, pegylated interferon and ribavirin. The mechanisms behind the inter-individual variation in response to interferon-based therapy had been elucidated by recent genome-wide association studies. The introduction of DAA therapy has resulted in a significant increase in SVR rate and given hope to patients with CHC in whom interferon is ineffective or contraindicated. The development of a therapeutic vaccine for HCV is, however, still in its infancy. This article will review the triumphs and tribulations of HCV therapy that have been witnessed over the last two decades.  相似文献   
60.
The main objective of the study was to perform the pharmacoeconomic analysis of synthetic disease-modifying anti-rheumatic drugs in rheumatoid arthritis patients. A prospective, observational study was conducted in 98 rheumatoid arthritis (RA) patients meeting 2010 Rheumatoid Arthritis Classification Criteria. Treatment-naive RA patients were initiated on synthetic disease-modifying anti-rheumatic drugs (DMARD/s) and followed up for 3 months. Average cost-effectiveness analysis was done by taking Health Assessment Questionnaire Disability Index (HAQ-DI) score as a measure of effectiveness. Out of the 98 RA patients, 15.30% were males and 84.69% females. 80.61% RA patients are seropositive. Majority of the study population patients (55%) were on combination of three synthetic DMARDs and almost a quarter (24.48%) were on combination of two synthetic DMARDs. The mean value of DAS 28 at baseline was 6.07 ± 1.33 and after 3 months treatment, the mean was 3.84 ± 1.11. The mean disability index measured by HAQ-DI was significantly reduced from 1.43 ± 0.71 to 0.81 ± 0.61, p < 0.001, after 3 months treatment. The direct medical cost of treatment of RA per month is 997.05 rupees. The average cost-effectiveness ratio of combination of synthetic DMARDs was 1533.92 rupees. Treatment of RA with synthetic DMARDs controls disease activity and improves disability with reasonable cost of treatment. The majority of the direct medical cost is attributable to cost of medicine and laboratory investigation. Use of quality generic drugs and an early diagnosis would minimize the economic burden on the patient.  相似文献   
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