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21.
22.
Ostial PV Isolation: 总被引:2,自引:0,他引:2
SABINE ERNST MATTHIAS ANTZ FEIFAN OUYANG THOMAS VOGTMANN MASAHIKO GOYA DIETMAR BÄNSCH ANSELM SCHAUMANN KARL-HEINZ KUCK 《Pacing and clinical electrophysiology : PACE》2003,26(7P2):1624-1630
Pulmonary vein (PV) isolation by elimination of spike potentials has been reported to cure drug refractory atrial fibrillation. Because of the heterogenous morphology of the PVs, sequential electroanatomic reconstruction of the PVs was performed in 39 patients (group A), who underwent subsequent PV isolation by interruption of all conductive myocardial fibers by distinct RF current applications using a "lasso" approach. In group B (157 patients), only biplane two-dimensional fluoroscopy was performed to guide the diagnostic and the ablation catheters. After reprocedures (in 7% of patients in group A and 22% of group B), which depicted a recurrence of a spike potential inside or at the ostium of >1 previously isolated PV in all restudied patients, stable sinus rhythm was documented in 69% of patients in group A and 60% of patients in group B. Reasons for the relapse of the previously eliminated spike potentials include a temporary ablation effect and a too distal interruption of the conducting myocardial fiber. Detailed knowledge of the individual three-dimensional morphology enhanced the clinical success rate of PV isolation but is time-consuming using CARTO (8.0 ± 1.7 vs 5.0 ± 1.6, P < 0.001) . Further technical improvement to fuse the individual three-dimensional anatomy and the electrophysiological markers to a composed "electroanatomic" map may overcome this limitation in the future. (PACE 2003; 26[Pt. II]:1624–1630) 相似文献
23.
Comprehensive approaches to tobacco use control 总被引:2,自引:0,他引:2
THOMAS J. GLYNN 《Addiction (Abingdon, England)》1991,86(5):631-635
This essay suggests approaches to two issues of importance to the future of tobacco use control research. First, there is need to identify those areas of tobacco use prevention and cessation research which have evolved to the point where additional investigation would only bring incremental gains. The reduction potential of this research should then be consolidated by applying existing, effective interventions widely and systematically. Conversely, there is need to identify those areas in which additional research is necessary. Second, the most logical way to reach agreement on those areas which are ready to move from research to applications-of-research is, with the co-operation and advice of the research community, through the large funding organizations which have supported this research over the past 2 decades. It is these organizations which, once the most effective interventions are identified, are capable of supporting the centrally-planned, consensus-driven, comprehensive approaches to tobacco use control which will be necessary to continued success in reducing tobacco-related morbidity and mortality in the industrialized world and to begin addressing the growing problems of tobacco use in the developing world. 相似文献
24.
An anomalous pulmonary vein draining into the subdiaphragmatic inferior vena cava was initially demonstrated on computed tomographic (CT) scans. The diagnosis of scimitar syndrome was confirmed with digital subtraction angiography. In retrospect, the anomalous vein and dextroposition of the heart were shown on chest radiographs. 相似文献
25.
A Decrease in Pulmonary Vein Diameter After Radiofrequency Ablation Predicts the Development of Severe Stenosis 总被引:3,自引:0,他引:3
ALEXANDER BERKOWITSCH THOMAS NEUMANN OKAN EKINCI HARALD GREISS THORSTEN DILL KLAUS KURZIDIM MALTE KUNISS HANS J. SCHNEIDER HEINZ F. PITSCHNER 《Pacing and clinical electrophysiology : PACE》2005,28(S1):S83-S85
A decrease in ostial pulmonary vein (PV) diameter was observed in patients on the day after radiofrequency ablation of atrial fibrillation (AF). This study examined whether a relative reduction in PV diameter on day 1 (RRPVD1) after the procedure predicts the late development of severe PV stenosis (PVS). The study included 104 consecutive patients (mean age = 55 years, range 46–61, 34 women) with drug refractory AF. Pulmonary vein diameter was measured using MR angiography (MRA) on the day before and on day 1 after the ablation procedure. The MRA was repeated every 3 months after the procedure. Severe PVS was defined as a >70% diameter reduction from the initial ostial diameter. The cut-off of RRPVD1 was prespecified as 25% decrease in initial diameter. The data are presented as medians and interquartile range. A total of 357 PV were treated. The RRPVD1 was 0.0% (0.0–11.1%). Severe PVS was found in 18 PV during a follow-up of 12 months (range 6–13). The log-rank analysis confirmed a strong association between a RRPVD1 ≥25% and the development of PVS (hazard ratio: 7.1; 95% confidence interval 3.8–13.5, P < 0.0001). By multivariate Cox regression model, after adjustment of procedure variables, RRPVD1 was the strongest predictor of development of severe PVS. RRPVD1 ≥25% was a strong independent predictor of development of severe PVS. 相似文献
26.
ETTER JEAN-FRANCOIS; PERNEGER THOMAS V.; ROUGEMONT ANDRE 《European journal of public health》1995,5(3):157-162
Factors affecting choice between a managed care organization(MCO) and a fee-for-service insurance plan were examined whenthe University of Geneva health insurance plan was transformedinto an MCO, in October 1992. A case-control study using a mailedquestionnaire (response rate 84%) was conducted to compare formermembers who joined the MCO (joiners, n=421) to former memberswho opted out in order to keep fee-for-service coverage (non-joiners,n=222). Non-joiners were more likely to be women (odds ratio(OR) from multivariate model was 1.15, p=0.50), to be born inSwitzerland (OR=2.04, p<0.01), to have an annual income >75,000Swiss francs (OR=2.00, p<0.01), to have a personal physician(OR=1.96, p<0.01) and to have consulted a specialist (OR=1.69,p=0.02) or used unconventional medicine (OR=4.59, p<0.01)in the past year. During the previous year, non-joiners hadmore health care visits than joiners (14.6 versus 9.1, p=0.01).Non-joiners reported better mental health and fewer complainedof persistent fatigue (OR=2.18, p=0.03). The choice of healthplan was strongly influenced by socio-demographic characteristics,past patterns of health services utilization and health status.The self-selection process was paradoxical: MCO joiners hadused fewer health care visits than non-joiners, but their self-reportedhealth status was worse. The differences we have observed betweenself-selected populations have important implications for thefinancial performance of competing health care delivery systems. 相似文献
27.
28.
C. BUCKLEY V. THOMAS J. LEWIN D. HARRIS M.H.A. RUSTIN 《Clinical and experimental dermatology》1994,19(2):149-151
A case of a West Indian patient is reported who developed abnormal blue-grey pigmentation on exposed areas of skin following treatment with low dose stelazine. Oculocutaneous melanosis is a well-recognized side-effect of prolonged phenothiazine treatment. In this condition the areas of skin exposed to sunlight develop a violaceous, blue-grey or slate-grey colour in more severe cases. These characteristic changes are rarely seen now. We describe the case of a patient who developed pigmentation while taking a low dose of stelazine for 5 years. 相似文献
29.
THOMAS T MACDONALD 《Pediatrics international》1994,36(5):532-536
The human mucosal immune system is structurally mature and has all the necessary cellular components to generate an immune response at birth. However, in the absence of dietary antigens and bacterial flora, there are no secondary follicles in the Peyer's patches and virtually no immunoglobulin A plasma cells in the lamina propria. Reactive follicle centers develop after birth but it takes 2 years for mucosal IgA plasma cell density to reach adult levels. T cells are present in the epithelium and lamina propria at birth, albeit at a lower frequency than later in life and there are major differences in phenotype between T cells in fetal intestine and postnatal intestine. There is no information on the impact of the massive antigenic challenge at birth on the mucosal immune system. Well-documented deficiencies in the ability of the blood T cells of the neonate to produce interleukin-4 and interferon-gamma may also occur in the intestine. It is still an open question whether it is better to try to prevent immunological sensitization of the newborn by avoiding potential allergens (i.e. cow's milk), or whether early exposure (as happens when premature infants are given formula feeds) might tolerize the infant. Hydrolysed cow's milk formulae are probably less antigenic than whole cow's milk and have been widely used in the treatment of cow's milk allergy. Some thought is now being given as to whether the prophylactic use of hydrolysates can reduce cow's milk allergy in ‘at-risk’ infants. 相似文献
30.
PARKER C. J. R.; OATES J. D. L.; BOYD A. H.; THOMAS S. D. 《British journal of anaesthesia》1994,72(2):181-184
We have assessed postoperative memory for lists of 10 neutralwords, presented by tape recording, in patients anaesthetizedby a standardized technique comprising thiopentone 5 mg kg1,midazolam 0.07 mg kg1, fentanyl 3 µg kg1and 70% nitrous oxide in oxygen, using both free recall anda test in which the subject was asked to indicate the presentedwords from a larger list. Twenty-four patients were exposedto one of four tape-recorded lists of words and 24 were presentedwith a blank tape. There was no instance of free recall of presentedwords. Analysis of the responses in the implicit memory testrevealed no difference between the performance of the patientswho had been exposed to a word list and those who had not. 相似文献