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71.
72.
Acute Pericarditis Resulting From an Endocardial Active Fixation Screw-In Atrial Lead 总被引:1,自引:0,他引:1
TREVOR O. GREENE ARTHUR S. PORTNOW SHOEI K. STEPHEN HUANG 《Pacing and clinical electrophysiology : PACE》1994,17(1):21-25
We examined the occurrence of acute pericarditis after pacemaker implantation in 123 consecutive patients (61 males, 62 females, ages 17–87 years) in whom a newer atrial active fixation bipolar lead was inserted endocardially in the right atrium for dual chamber pacing. The atrial leads were positioned to obtain the best possible pacing and sensing thresholds, after an initial attempt was made for insertion into the right atrial appendage or medially into the right atrial septum. Six patients (4.9%) developed acute symptomatic pericarditis with effusion within 24 hours of implantation. Of these six patients, four had leads screwed into the lateral waH. and the other two had leads placed in the anterolateral wall. The lead implantation parameters between patients with pericarditis and those without did not show any significant difference in the atrial P wave amplitude (2.3 ± 0.4 vs 2.9 ± 0.9 mV), pacing threshold (1.1 ± 0.2 vs 1.1 ± 0.4 V), or resistance (524 ± 112 vs 480 ± 94 ohms). All symptomatic patients were treated with nonsteroidal anti-inflammatory drugs with symptoms resolving in 1–2 weeks. We condude that: (1) a significant number of patients (4.9%) developed acute symptomatic pericarditis after insertion of this type of atrial fixation lead: (2) because of the lead design, the implantation parameters coud not be taken to predict the occurrence of pericarditis: and (3) caution should be taken for the insertion of this lead into the thin atrial wall. 相似文献
73.
T. BEN MORRISON M.D. ROBERT F. REA M.D. DAVID O. HODGE M.S. DANIEL CRUSAN B.S. CELESTE KOESTLER R.N. SAMUEL J. ASIRVATHAM M.D. DAVID BRADLEY M.D. Ph.D. WIN K. SHEN M.D. THOMAS M. MUNGER M.D. STEPHEN C. HAMMILL M.D. PAUL A. FRIEDMAN M.D. 《Journal of cardiovascular electrophysiology》2010,21(6):671-677
Risk Factors for ICD Lead Fracture. Introduction: The Medtronic Sprint Fidelis® implantable cardioverter defibrillator (ICD) lead was “recalled” in October 2007 after 268,000 implants worldwide due to increased failure risk. Manufacturer suggested monitoring has not been shown effective at preventing adverse events. Only limited data exist regarding clinical predictors of Fidelis® lead fracture. We sought to identify risk factors for Fidelis® fracture to guide clinical monitoring and compare its performance with a control lead. Methods: Fractured lead cases were retrospectively reviewed for demographic data, implant technique, radiographic appearance and clinical presentation was analyzed. Lead survival was compared using Kaplan‐Meir curves. Results: Study patients (n = 1314) experienced 18 Fidelis® and 6 Quattro? lead fractures. Patients with failed Fidelis® leads were younger than those with surviving leads (49.5 vs 64.6 years, P = 0.0066). Fidelis® lead fractures often occurred around the time of physical activity. No other measured demographic or technique related factors were associated with lead fracture. Fidelis® leads had significantly decreased survival compared with Quattro? leads (89.3 vs 98.9% at 30 months). Patients less than 50 years old had significantly decreased lead survival compared with those older than 50 in both Fidelis® (79.6% vs 96.5% at 24 months) and Quattro? (93.4 vs 99.8%, P < 0.001 at 24 months) leads. Conclusions: Patients under age 50, with either Fidelis® or Quattro? ICD leads, are at increased risk of lead fracture compared with patients over 50, particularly around the time of intense physical activity. Aggressive monitoring and advisory programming appears warranted in patients with Fidelis® leads as well as especially in younger patients. (J Cardiovasc Electrophysiol, Vol. 21, pp. 671‐677, June 2010) 相似文献
74.
CAROLE A TUCKER PHD PT PCS ; GEORGE E GORTON BS ; KYLE WATSON DPT ; MARIA A FRAGALA-PINKHAM MS PT ; HELENE M DUMAS MS PT ; KATHLEEN MONTPETIT MSCOT ; NATHALIE BILODEAU MSCOT ; PENGSHENG NI MD ; RONALD K HAMBLETON PHD ; STEPHEN M HALEY PHD PT 《Developmental medicine and child neurology》2009,51(9):717-724
The objective of this project was to develop computer-adaptive tests (CATs) using parent reports of physical function in children and adolescents with cerebral palsy (CP). The specific aims of this study were to (1) examine the psychometric properties of an item bank of lower-extremity and mobility skills for children with CP; (2) evaluate a CAT using this item bank; (3) examine the concurrent validity of the CAT with the Pediatric Outcomes Data Collection Instrument (PODCI) and the Functional Assessment Questionnaire (FAQ); and (4) establish the discriminant validity of simulated CATs with Gross Motor Function Classification System (GMFCS) levels and CP type (diplegia, hemiplegia, or quadriplegia). Parents ( n =190) of children and adolescents with spastic diplegic (48%), hemiplegic (22%), or quadriplegic (30%) CP consisting of 108 males and 82 females with a mean age of 10 years 7 months (SD 4y 1mo, range 2–21y) and in GMFCS levels I to V participated in item pool calibration and completed the PODCI and FAQ. Confirmatory factor analyses supported a unidimensional model for the 45 basic lower-extremity and mobility items. Simulated CATs of 5, 10, and 15 items demonstrated excellent accuracy (intraclass correlation coefficients [ICCs] >0.91) with the full item bank and had high correlations with PODCI transfers and mobility (ICC = 0.86) and FAQ scores (ICC = 0.77). All CATs discriminated among GMFCS levels and CP type. The lower-extremity and mobility skills item bank and simulated CATs demonstrated excellent performance over a wide span of ages and severity levels. 相似文献
75.
JENNIFER L. POMERANZ STEPHEN P. TERET STEPHEN D. SUGARMAN LAINIE RUTKOW KELLY D. BROWNELL 《The Milbank quarterly》2009,87(1):185-213
Context: The law is a powerful public health tool with considerable potential to address the obesity issue. Scientific advances, gaps in the current regulatory environment, and new ways of conceptualizing rights and responsibilities offer a foundation for legal innovation.
Methods: This article connects developments in public health and nutrition with legal advances to define promising avenues for preventing obesity through the application of the law.
Findings: Two sets of approaches are defined: (1) direct application of the law to factors known to contribute to obesity and (2) original and innovative legal solutions that address the weak regulatory stance of government and the ineffectiveness of existing policies used to control obesity. Specific legal strategies are discussed for limiting children's food marketing, confronting the potential addictive properties of food, compelling industry speech, increasing government speech, regulating conduct, using tort litigation, applying nuisance law as a litigation strategy, and considering performance-based regulation as an alternative to typical regulatory actions. Finally, preemption is an overriding issue and can play both a facilitative and a hindering role in obesity policy.
Conclusions: Legal solutions are immediately available to the government to address obesity and should be considered at the federal, state, and local levels. New and innovative legal solutions represent opportunities to take the law in creative directions and to link legal, nutrition, and public health communities in constructive ways. 相似文献
Methods: This article connects developments in public health and nutrition with legal advances to define promising avenues for preventing obesity through the application of the law.
Findings: Two sets of approaches are defined: (1) direct application of the law to factors known to contribute to obesity and (2) original and innovative legal solutions that address the weak regulatory stance of government and the ineffectiveness of existing policies used to control obesity. Specific legal strategies are discussed for limiting children's food marketing, confronting the potential addictive properties of food, compelling industry speech, increasing government speech, regulating conduct, using tort litigation, applying nuisance law as a litigation strategy, and considering performance-based regulation as an alternative to typical regulatory actions. Finally, preemption is an overriding issue and can play both a facilitative and a hindering role in obesity policy.
Conclusions: Legal solutions are immediately available to the government to address obesity and should be considered at the federal, state, and local levels. New and innovative legal solutions represent opportunities to take the law in creative directions and to link legal, nutrition, and public health communities in constructive ways. 相似文献
76.
77.
Myotropic peptides are structurally dissimilar; thus, they comprise different families. The cellular expressions of myotropins suggest they act as hormones, transmitters, and modulators of numerous biological processes. Drosophila melanogaster allatostatin (AST), FMRFamide-containing, dromyosuppressin (DMS), and drosulfakinin (DSK) peptides represent four different myotropin families. A different gene encodes each of these four myotropin families. D. melanogaster AST, FMRFamide-containing, DMS, and DSK peptides are present in neural and gut tissue, but are not all expressed in the same cells. These four families of myotropins affect spontaneous contractions of gut, heart, and/or reproductive tissue, but their effects are dissimilar in magnitude and time course. Based on their structures, genes, distributions, and activities, the synthesis and release of these D. melanogaster myotropins are likely governed by different sensory inputs and regulatory mechanisms. The differences in structures, precursors, cellular expressions, and activities are consistent with the conclusion that they do not play redundant roles in their effects on the frequency of muscle contractions. Orthologs of these D. melanogaster myotropins exist in other animal species; thus, research on the mechanisms involved in their production and processing, functions, and signaling may be widely applicable. Here, we review research on D. melanogaster AST, FMRFamide-containing, myosuppressin, and sulfakinin peptides. 相似文献
78.
KIMBERLEY SALMON JANET WHITTAM STEPHEN FREEBORN 《The International journal of pharmacy practice》2001,9(Z1):65-65
□ The quality of patient care could potentially improve through patients' own drugs (POD) schemes □ POD schemes need to be promoted to primary care professionals 相似文献
79.
80.
Flecainide Induced Atrial Tachycardia with 1:1 Ventricular Conduction During Exercise Testing 总被引:1,自引:0,他引:1
DOMENICK N. RANDAZZO PAUL SCHWEITZER ELLIOT STEIN JOHN S. BANAS Jr. STEPHEN L. WINTERS 《Pacing and clinical electrophysiology : PACE》1994,17(9):1509-1514
Wide complex tachycardias may represent a rare proarrhythmic effect of some antiarrhythmic agents. The authors describe a patient who developed a wide complex tachycardia developing during stress testing while on therapy with flecainide, and the difficulty in interpreting the electrocardiogram. This article reviews potential proarrhythmic effects of flecainide in the treatment of atrial dysrhythmias and the difficulty in differentiating associated wide complex tachycardias. 相似文献