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51.
52.
Multiparametric Analysis of Heart Rate Variability Used for Risk Stratification Among Survivors of Acute Myocardial Infarction 总被引:5,自引:0,他引:5
ANDREAS VOSS KATERINA HNATKOVA NIELS WESSEL JUERGEN KURTHS RE SANDER ALEXANDER SCHIRDEWAN A JOHN CAMM MAREK MALIK 《Pacing and clinical electrophysiology : PACE》1998,21(1):186-196
A multiparametric heart rate variability analysis was performed to prove if combined heart rate variability (HRV) measures of different domains improve the result of risk stratification in patients after myocardial infarction. In this study, standard time domain, frequency domain and non-linear dynamics measures of HRV assessment were applied to 572 survivors of acute myocardial infarction. Three parameter sets each consisting of 4 parameters were applied and compared with the standard measurement of global heart rate variability HRVi. Discriminant analysis technique and t-test were performed to separate the high risk groups from the survivors. The predictive value of this approach was evaluated with receiver operator (ROC) and positive predictive accuracy (PPA) curves. Results - The discriminant analysis shows a separation of patients suffered by all cause mortality in 80% (best single parameter 74%) and sudden arrhythmic death in 86% (73%). All parameters of set I show a high significant difference (p<0.001) between survivors and non-survivors based on two-tailed t-test. The specificity level of the multivariate parameter sets is at the 70% sensitivity level (ROC) about 85–90%, whereas HRVi shows maximum levels of 70%. The PPA in the all cause mortality group is at the 70% sensitivity level twice as high as the univarihate HRV measure and increases to more than fourfold as high within the VT/VF group. In conclusion, in this population, the multiparametric approach with the combination of four parameters from all domains especially from NLD seems to be a better predictor of high arrhythmia risk than the standard measurement of global heart rate variability. 相似文献
53.
M. LEMNAOUAR E. CHASTRE† A. PAUL M. MERGEY D. VEISSIÈRE G. CHERQUT P. BARBRY‡ B. SIMON-BOUY§ P. FANEN¶ C. GESPACH† J. PICARD 《European journal of clinical investigation》1993,23(3):151-160
Abstract. Primary tracheal epithelial cells obtained from two fetuses with cystic fibrosis (CF) were successfully transfected with a plasmid vector recombined with the large T oncogene of SV40. The resulting tracheal cells were propagated in culture for up to 25 passages and retained the mutations of the CF genes carried by the two fetuses, one heterozygous for the S549N and N1303K substitutions (CFT-I cells), and the other homozygous for the most common deletion ΔF508 (CFT-2 cells). The transfected cells: (a) expressed the SV40 large T oncogene, as determined by immunofluorescence and Northern blot analysis; (b) retained typical epithelial morphology, as assessed by the presence of microvilli, desmosomes, gap junctions, and cytokeratin expression; (c) were fully responsive to the cAMP-stimulating agents isproterenol, forskolin and vasoactive intestinal peptide for cAMP production and PKA activation; (d) do not produce any tumour in the athymic nude mice; (e) were diploid and tetraploid with a normal chromosomal complement at early passages, and (f) exhibited the abnormal regulation of chloride conductance characteristic of CF.
These results indicate that CFT-1 and CFT-2 cells constitute a suitable model for: (a) comparison of the maturation and function of the CFTR protein mutated in the two nucleotide-binding domains; (2) analysis of the biochemical defect in CF epithelial airway cells, (c) development of new therapeutic agents, and correction of the CF defect by gene replacement therapy in vitro . 相似文献
These results indicate that CFT-1 and CFT-2 cells constitute a suitable model for: (a) comparison of the maturation and function of the CFTR protein mutated in the two nucleotide-binding domains; (2) analysis of the biochemical defect in CF epithelial airway cells, (c) development of new therapeutic agents, and correction of the CF defect by gene replacement therapy in vitro . 相似文献
54.
VERONIQUE MAHAUX YVES VERBOVEN RE WALEFFE HENRI KULBERTUS 《Pacing and clinical electrophysiology : PACE》1992,15(11):1862-1866
A sensor driven algorithm limiting ventricular pacing rate during supraventricular tachycardia (SVT) is included in a dual chamber rate modulated pacemaker sensitive to acceleration forces (Relay, 294-03, Intermedics Inc.). According to the intensity of concomitant exercise, the ventricular pacing rate is limited either to the programmed maximum pacing rate (MPR) or to an interim lower limit, called "conditional ventricular tracking limit" (CVTL). The MPR prevails over the CVTL when the sensor calculated pacing rate exceeds the minimal rate by more than 20 beats/mm. The purpose of the study is to determine the clinical safety and efficacy of this algorithm in patients with intermittent SVT. Method: a Relay was implanted in four patients with a bradycardia/tachycardia syndrome and in four patients with complete atrioventricular block (CAVB). All had episodes of paroxysmal atrial tachycardia. The units were programmed in DDDR: rate responsive parameters were adjusted by simulating the rate response during three levels of exercise to let the MPR override the CVTL only during strenuous exercise. Holter monitors and exercise testings were performed at 3-month follow-up. Results: in seven patients, Holter recordings showed Supraventricular arrhythmias at rest with a ventricular pacing rate limited to the CVTL. Appropriate rate increases during exercise testings were also demonstrated. Three devices had to be reprogrammed in DDIR tone patient suffering from nearly permanent atrial flutter and two patients not tolerating the CVTL pacing rate at rest). Conclusion: the CVTL algorithm is effective in protecting against high ventricular pacing rates during Supraventricular arrhythmias. It allows the selection of the DDDR mode even with a high MPR in patients with intermittent SVT. 相似文献
55.
ALADAR RONASZEKI HUGO ECTOR BOUDEWIJN DENEF RE E. AUBERT VAN DE WERF HILAIRE DE GEEST 《Pacing and clinical electrophysiology : PACE》1990,13(12):1728-1731
RONASZEKI, A., ET AL.: Effect of Short Atrioventricular Delay on Cardiac Output. Short atrioventricular (AV) delay modifies late diastolic filling dynamics. The effect of this change on cardiac output [CO) was studied in closed chest, AV blocked canine preparations (N: 10), during AV sequential pacing (80 bpm). CO (thermodilution technique) and transmitral flow velocity (TMFV, pulsed-wave Doppler) were measured and compared (paired t-test) on the basis of TMFV pattern, when atrial contraction (A wave) started just after early diastolic transmitral flow deceleration [PR:219 ± 25 ms, mean ± SD) and when A wave occurred at the end of late diastole and shortened due to the next ventricular contraction (PR: 56 ± 11 ms). The short AV delay resulted in 12.0 ± 5.9% decrease of CO, reflecting the interrupted late diastolic atrial transport. Properly timed atrial contraction is necessary for optimal AV sequential pacing. 相似文献
56.
Coxon RE; Fekade D; Knox K; Hussein K; Melka A; Daniel A; Griffin GG; Warrell DA 《QJM : monthly journal of the Association of Physicians》1997,90(3):213-221
Severe Jarisch Herxheimer reaction (J-HR) precipitated by antibiotic
treatment of louse-borne relapsing fever (LBRF) is associated with a
transient, marked rise in circulating tumour necrosis factor alpha (TNF
alpha), interleukin 6 (IL-6) and interleukin 8 (IL-8). Ovine polyclonal
anti-TNF alpha antibody fragments (Fab) were used in a randomized double
blind placebo controlled trial in an attempt to prevent this reaction.
Within 4 h after penicillin, in controls (n = 29), a several- fold rise in
cytokines occurred, concomitant with a fall in spirochaetes and maximal
clinical manifestations of the J-HR. An intravenous infusion of anti-TNF
alpha Fab, 30 min before penicillin in 20 patients reduced peak plasma
levels of IL-6 and IL-8 (but not IL-1 beta) compared with controls (p =
0.01 and < 0.001, respectively) and the incidence of the J-HR,
indicating some neutralization of TNF alpha. An apparent fall in TNF alpha
reflected interference of anti-TNF alpha in the immunoassay.
相似文献
57.
58.
Major complications after 400 continuous popliteal sciatic nerve blocks for post‐operative analgesia
V. COMPÈRE N. REY O. BAERT A. OUENNICH V. FOURDRINIER X. ROUSSIGNOL R. BECCARI B. DUREUIL 《Acta anaesthesiologica Scandinavica》2009,53(3):339-345
Background: A continuous popliteal sciatic nerve block (CPSNB) has been performed with increasing frequency for post‐operative analgesia after foot surgery. Major complications associated with the placement of a perineural catheter remain rarely studied. The aim of this study was to prospectively determine the incidence of major complications (neurological and infectious) in post‐operative adult patients with a continuous popliteal catheter inserted by the anatomical posterior approach for analgesia after foot surgery. Methods: All popliteal catheters were placed pre‐operatively under sterile conditions with the aid of a nerve stimulator technique. The primary outcome measure was the incidence of major complications including infection and neuropathy. As a secondary outcome, adverse effects as well as other complications were also evaluated. Data were expressed as median [25th–75th percentiles]. Results: A total of 400 patients were included in the study during a 2‐year period. The median time the catheter remained indwelling was 47 h [23, 54]. Major complications included three events (0.75%) with one infection (0.25%) and two neuropathies (0.50%). Three blocks were unsuccessful and the catheter insertion was difficult in 12 patients (3%). During the CPSNB procedure, one patient reported slight paraesthesia during stimulation. Patient satisfaction was scored at 4 for 89%, 3 for 6% and 2 for 5% on the analogue scale. Conclusions: Major complications after the use of CPSN are not in fact rare. The incidence of severe neuropathy or infection complications is, respectively, 0.50% and 0.25%. However, the insertion of CPSN could be considered effective and is associated with only a few minor complications. 相似文献
59.
The present study focuses on the validity of questionnaire self-report of psychopathology and parent-child relationship quality for juvenile delinquents with severe behavioural and psychiatric disorders by comparing information derived from questionnaire self-report with information from other sources, including parent report, in-depth interviewing, behavioural observation by clinicians, and official criminal records. The sample consisted of N=33 juvenile delinquents with psychiatric disorders. The juvenile delinquents did not report increased levels of psychopathology or poor relationships with their parents, which is inconsistent with the fact that all juvenile delinquents were in day treatment for severe behavioural maladaptation and relationship problems. Moreover, parent ratings of psychopathology were consistently in the clinical range and relationship quality was evaluated as very poor by the parents (d>.80). We conclude that screening instruments for psychopathology and assessment of relationship quality relying on questionnaire self-report may not yield valid scores in this (extreme) population of juvenile delinquents. 相似文献
60.
目的:探讨三维适形放疗结合锎(252Cf)中子腔内后装照射治疗中晚期食管癌的疗效、不良反应及晚期并发症。方法:92例中晚期食管癌患者全部采用三维适形放疗结合锎(252Cf)中子腔内后装照射治疗。三维适形放疗总剂量为45Gy-54Gy,分25-30次,5-6周完成;腔内照射3-4Gy/次,1次/周,共2-4次,总吸收剂量10Gy-16Gy。结果:治疗结束3个月进食梗阻缓解率为95%。近期疗效:完全缓解(CR)27%,部分缓解(PR)69.6%。1、2、3年局部控制率分别为82%、51%、32%;1、2、3年生存率分别为:78%、35%、18%;急性放射性食管炎发生率为54%;晚期食管狭窄发生率9%;食管穿孔发生率2%。结论:中晚期食管癌采用三维适形放疗结合锎(252Cf)中子腔内后装照射能够迅速而持久地缓解进食梗阻症状,提高局部控制率及生活质量,近期疗效显著,放疗不良反应未见明显增加。 相似文献