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101.
OBJECTIVES: The purpose of this study was to determine both treatment gaps and predictors of warfarin use in atrial fibrillation (AF) patients enrolled in a national multicenter study. BACKGROUND: The National Anticoagulation Benchmark Outcomes Report (NABOR) is a performance improvement program designed to benchmark anticoagulation prophylaxis, treatment, and outcomes among participating hospitals. METHODS: A retrospective cohort study of inpatients was performed at 21 teaching, 13 community, and 4 Veterans Administration hospitals in the U.S. Patients with an ICD-9-CM code for AF (427.31) were randomly selected. RESULTS: Among the 945 patients studied, the mean age was 71.5 (+/- 13.5) years; 43% were >75 years of age, 54.5% were men, and 67% had a history of hypertension. Most (86%) had factors that stratified them as at high risk of stroke, and only 55% of those received warfarin. Neither warfarin nor aspirin were prescribed in 21% of high-risk patients, including 18% of those with a previous stroke, transient ischemic attack, or systemic embolic event. Age >80 years (p = 0.008) and perceived bleeding risk (p = 0.022) were negative predictors of warfarin use. Persistent/permanent AF (p < 0.001) and history of stroke, transient ischemic attack, or systemic embolus (p = 0.014) were positive predictors of warfarin use, whereas high-risk stratification was not. CONCLUSIONS: This study confirms the under-use of warfarin, but also adds to published reports in several regards. It showed that risk stratification, the guidepost for treatment in international guidelines, had little effect on warfarin use, and that age >80 years and AF classification (permanent/persistent) are factors that influence warfarin use.  相似文献   
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OBJECTIVE: The purpose of this study was to determine the feasibility of prenatal sonography for detecting velamentous insertion of the umbilical cord in singleton pregnancies at the 11- to 14-week scan. METHODS: The placental umbilical cord insertion site was prospectively examined at the time of the routine first-trimester scan between 11 and 14 weeks as part of ongoing first-trimester sonographic screening for chromosomal abnormalities. RESULTS: Over a 1-year period, 533 consecutive singleton pregnancies were examined by a fetal medicine specialist at a median gestational age of 12 weeks. In 5 cases, a velamentous umbilical cord insertion was diagnosed, with a prevalence rate of 1 (0.9%) per 107. The diagnosis was further confirmed at the second-trimester scan and at the time of delivery in all cases. CONCLUSIONS: The placental umbilical cord insertion site can be readily determined by sonography at the time of the 11- to 14-week scan. Sonographic examination at this early gestational age provides the opportunity for screening for velamentous insertion of the umbilical cord in the first trimester, allowing close surveillance of the pregnancy for potential complications associated with this condition.  相似文献   
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The spontaneous onset and termination of many episodes of paroxysmal tachycardia, each initiated by an atrial premature depolarization, were studied in one patient. Surface electrocardiograms alone were inadequate to define the mechanisms underlying the frequent irregularity of atrial and ventricular cycle lengths during the tachycardia and the nature of spontaneous termination of the tachycardia. Unipolar atrial electrograms demonstrated that the irregularity during the tachycardia was due to premature atrial depolarizations that reset the reentrant cycle sustaining the tachycardia, and each spontaneous termination was due to an even more premature atrial depolarization interrupting the reentrant pathway. The genesis of the atrial premature depolarizations resetting and terminating the tachycardia, and their relationship to those initiating the tachycardia, are discussed.  相似文献   
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A S Geha  L A Biblo  M D Carlson  A L Waldo 《The Annals of thoracic surgery》1992,53(2):200-5; discussion 205-6
From September 1986 through September 1990, 60 operations were performed in 55 patients (32 male and 23 female; age, 1 to 76 years) for ablation of accessory pathways of atrioventricular reentrant tachycardia; 6 patients had additional cardiac procedures. Between September 1986 and August 1988 the initial surgical approach was exclusively epicardial with adjuvant cryoablation (EPI) in 23 patients (group 1) for a left free wall (LFW) pathway in 11, right free wall (RFW) in 3, posteroseptal (PS) in 7, and anteroseptal in 2. During September 1988 through September 1990, 32 patients (group 2) had the initial surgical approach tailored to the location of the mapped accessory pathway: endocardial approach (ENDO) for LFW in 17 and for juxtanodal pathway in 2, EPI for RFW in 3 and for PS in 9, and combined ENDO and EPI for AS in 1. There was no early or late death in either group. In group 1, 2 patients with LFW pathway had development of recurrent preexcitation in the same compartment requiring ENDO reoperation 10 and 11 months later, 1 with anteroseptal pathway needed immediate ENDO and EPI reoperation, and another with LFW, who required pericardial patch repair of a left atrial tear, had a thromboembolic stroke 2 days later. No serious complications occurred in group 2, but 2 patients with PS required reoperation before discharge for a second accessory pathway in another compartment (1 RFW and 1 LFW). Additionally, 4 patients (2 in each group) had from the beginning ablation of two pathways in different compartments. On complete late follow-up (mean, 28 months) all patients are back to preoperative levels of activity and are free of preexcitation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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There is currently a need for diagnostic electron microscopy in both autopsy and surgical pathology. As more information emerges from the research laboratories, applied electron microscopy will grow in depth, and all large medical centers will need the expertise provided by a diagnostic electron microscopy laboratory. Many physicians other than electron microscopists find it essential to have an understanding of the contributions and limitations of electron microscopy. Education and training programs therefore must encompass not only paramedical personnel who prepare the electron micrographs and pathologists who are thoroughly trained to interpret the electron micrographs, but also other physicians and scientists who utilize the information obtained therefrom. Medical students should obtain sufficient background in normal and abnormal ultrastructure to enable them to interpret the medical literature, and the means to obtain this background should be available within the medical school curriculum. Some medical students will also desire more thorough training obtained by elective courses in electron microscopy. Pathology residents should obtain sufficient expertise during their residency to enable them to utilize the information produced by the electron microscopy laboratory. Certain pathology residents and some pathologists in practice prefer fellowships for more specialized training in electron microscopy.Four representative training programs in electron microscopy from Veterans Administration hospitals have been selected for presentation. Each emphasizes a different approach and different objectives.  相似文献   
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