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81.
BackgroundAsymptomatic atrial fibrillation is often detected incidentally. Prognosis and optimal therapy for asymptomatic compared with symptomatic atrial fibrillation is uncertain. This study compares clinical characteristics, treatment, and 2-year outcomes of asymptomatic and symptomatic atrial fibrillation presentations.MethodsGlobal Anticoagulant Registry in the Field-Atrial Fibrillation (GARFIELD-AF) is a global, prospective, observational study of newly diagnosed atrial fibrillation with ≥1 stroke risk factors (http://www.clinicaltrials.gov, unique identifier: NCT01090362). Patients were characterized by atrial fibrillation-related symptoms at presentation and the CHA2DS2-VASc score. Two-year follow-up recorded anticoagulation patterns (vitamin K antagonist, direct oral anticoagulants, parenteral therapy) and outcomes (stroke/systemic embolism, all-cause mortality, and bleeding).ResultsAt presentation, of 52,032 eligible patients, 25.4% were asymptomatic and 74.6% symptomatic. Asymptomatic patients were slightly older (72 vs 70 years), more often male (64.2% vs 52.9%), and more frequently initiated on anticoagulation ± antiplatelets (69.4% vs 66.0%). No difference in events (adjusted hazard ratios, 95% confidence interval) for nonhemorrhagic stroke/systemic embolism (1.19, 0.97-1.45), all-cause mortality (1.06, 0.94-1.20), or bleeding (1.02, 0.87-1.19) was observed. Anticoagulation was associated with comparable reduction in nonhemorrhagic stroke/systemic embolism (0.59, 0.43–0.82 vs 0.78, 0.65–0.93) and all-cause mortality (0.69, 0.59-0.81 vs 0.77, 0.71-0.85) in asymptomatic versus symptomatic, respectively.ConclusionsMajor outcomes do not differ between asymptomatic and symptomatic atrial fibrillation presentations and are comparably reduced by anticoagulation. Opportunistic screening-detected asymptomatic atrial fibrillation likely has the same prognosis as asymptomatic atrial fibrillation at presentation and likely responds similarly to anticoagulation thromboprophylaxis.  相似文献   
82.
Clinical Rheumatology - Osteitis condensans ilii (OCI) is a benign condition characterised by triangular sclerosis of the iliac bone which may mimic radiographic sacroiliitis. Prevalence is...  相似文献   
83.
The prevalence of atrial fibrillation (AF) is forecast to rise to 2–5% of the general population by 2050. Of the two fundamental treatment strategies for AF management, rhythm control is the approach which is generally preferred for active, symptomatic, and/or younger patients, whereas rate control is all that is found necessary in the more elderly, sedentary, asymptomatic individual. In many cases, at neither extreme, there remains a genuine choice of therapy, and for those patients, antiarrhythmic strategies would be preferred if effective and safe antiarrhythmic medications were available. Many new antiarrhythmic agents exploiting new mechanisms of action or novel combinations of established antiarrhythmic activity are currently being investigated. Agents which selectively inhibit ion channels specifically involved in atrial repolarization, so-called atrial repolarization delaying agents, are widely acknowledged as potentially ideal antiarrhythmic treatments, as they will probably be both effective and safe, at the very least (free of pro-arrhythmic effects at the ventricular level). Modified analogues of traditional antiarrhythmic drugs with different combinations of ion channel and receptor blocking effects, novel mechanisms of action, and less complicated metabolic profiles are also under development. Completely innovative antiarrhythmic agents with new antiarrhythmic mechanisms, such as stretch receptor antagonism, sodium calcium exchanger blockade, late sodium channel inhibition, and gap junction modulation are also being explored. In addition, there is increasing evidence in support of the antiarrhythmic action of non-antiarrhythmic drugs. Treatments with statins, omega-3 fatty acids, angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, and aldosterone antagonists are all potentially valuable, over and above any effect related to the treatment of underlying heart disease. Professor A. John Camm is a consultant to AstraZeneca, Cardiome, sanofi aventis, and Xention.  相似文献   
84.
Follicular lymphoma international prognostic index   总被引:14,自引:14,他引:14       下载免费PDF全文
The prognosis of follicular lymphomas (FL) is heterogeneous and numerous treatments may be proposed. A validated prognostic index (PI) would help in evaluating and choosing these treatments. Characteristics at diagnosis were collected from 4167 patients with FL diagnosed between 1985 and 1992. Univariate and multivariate analyses were used to propose a PI. This index was then tested on 919 patients. Five adverse prognostic factors were selected: age (> 60 years vs 60 years), Ann Arbor stage (III-IV vs I-II), hemoglobin level (< 120 g/L vs 120 g/L), number of nodal areas (> 4 vs 4), and serum LDH level (above normal vs normal or below). Three risk groups were defined: low risk (0-1 adverse factor, 36% of patients), intermediate risk (2 factors, 37% of patients, hazard ratio [HR] of 2.3), and poor risk ( 3 adverse factors, 27% of patients, HR = 4.3). This Follicular Lymphoma International Prognostic Index (FLIPI) appeared more discriminant than the International Prognostic Index proposed for aggressive non-Hodgkin lymphomas. Results were very similar in the confirmation group. The FLIPI may be used for improving treatment choices, comparing clinical trials, and designing studies to evaluate new treatments.   相似文献   
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The clinical electrophysiologic approaches to atrial flutter (F) have been activation mapping and the observation of changes induced by programmed stimulation. Sequential endocardial activation mapping has recently yielded information indicating that common F is produced by a large right atrial (RA) reentry circuit, with counterclockwise rotation in the frontal plane, including the inferior vena cava in its center. Functional block in the crista terminalis and conduction slowing in the approaches to the atrioventricular node seem to be important to support reentry. F inscribing positive deflections in the inferior leads usually follows the same path, but in a clockwise direction. Atypical F may be produced by left atrial circuits. Atrial stimulation during F entrains the circuit, resetting it with each stimulus. Collision between antidromic and orthodromic activation during entrainment produces fusion that can be identified in the surface electrocardiogram. The last paced activation restarts F, unless circuit penetration has been enough to modify it by block or disorganization. Entrainment may result in F acceleration, with changes in activation sequence, suggesting a different type of reentry, possibly based on functional factors.  相似文献   
87.
OBJECTIVE--A comparison of the efficacy of verapamil, sotalol, and flecainide to suppress right ventricular tachycardia (VT) in patients with a clinically normal heart. DESIGN--Patients underwent treatment serially with verapamil (360 mg daily), sotalol (240 or 320 mg daily), and flecainide (200 or 300 mg daily), (the larger dose was for patients heavier than 80 kg) to suppress tachycardia. Each drug was given orally for five half lives before testing. PATIENTS--23 patients with right VT associated with a clinically normal heart were studied. OUTCOME MEASURES--The effects of drug treatment were examined by the number of ventricular events on 24 hour Holter monitoring, and the ability of tachycardia to be induced by treadmill exercise testing (Bruce protocol) and programmed ventricular stimulation (Wellens protocol), compared with drug free baseline tests. SETTING--Patients were studied in a tertiary referral centre. RESULTS--All three drugs suppressed ventricular salvos (> 3, < 5 consecutive ventricular premature contractions) (p < 0.01) and VT (p < 0.05) on Holter monitoring and did not differ statistically in effect. Exercise induced VT was also suppressed by all three drugs (p < 0.01), and of these sotalol was the most effective although this was not statistically significant (14/23 inducible when drug free, 4/23 on flecainide, 2/23 on sotalol, 5/23 on verapamil). Sustained and non-sustained VT induced by programmed stimulation was also suppressed by the three drugs (p < 0.01) and again sotalol was the best of these though the differences did not achieve statistical significance (17/23 inducible when drug free, 4/17 on flecainide, 2/17 on sotalol, and 6/17 on verapamil). Proarrhythmic effects of drugs were found in a few patients. There was no difference in the efficacy of the drugs in patients with histological abnormalities of the myocardium when compared with those of normal histology. CONCLUSIONS--Ventricular tachycardia associated with a clinically normal heart can be suppressed by flecainide, sotalol, or verapamil. In individual patients sotalol was the most frequently effective drug (effective in > 89% of patients) and is a suitable choice for first line treatment.  相似文献   
88.
Pediatric peripheral blood stem cell collection (PBSC) is challenging because it has potentially more side effects than in adults due to the small body mass and unique physiology of children. The extracorporeal volume of the cell separator device, poor venous access and metabolic complications due to citrate toxicity are the main problems to face during PBSC collection. These aspects are more relevant in very low body weight (BW) children of 20?kg or lower. An efficient, experienced and well-prepared team of pediatricians, apheresis physicians and nurses, and physicians involved in CVC positioning is crucial to performing a safe PBSC collection. Despite the growing demand for PBSC collection in the pediatric setting, there is not an actual unique standardized detailed practice approach to be employed, therefore, on reflection, we believe that it is timely to draw up useful evidence-based recommendations on which guidelines can be developed for use by those groups with limited or no experience.  相似文献   
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