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61.
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
62.
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
63.
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
64.
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
65.
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
66.
67.
Vincent J. C. Lempers Jeroen J. M. W. van den Heuvel Frans G. M. Russel Rob E. Aarnoutse David M. Burger Roger J. Brüggemann Jan B. Koenderink 《Antimicrobial agents and chemotherapy》2016,60(6):3372-3379
Inhibition of ABC transporters is a common mechanism underlying drug-drug interactions (DDIs). We determined the inhibitory potential of antifungal drugs currently used for invasive fungal infections on ABC transporters P-glycoprotein (P-gp), MRP1 to MRP5, BCRP, and BSEP in vitro. Membrane vesicles isolated from transporter-overexpressing HEK 293 cells were used to investigate the inhibitory potential of antifungal drugs (250 μM) on transport of model substrates. Concentration-inhibition curves were determined if transport inhibition was >60%. Fifty percent inhibitory concentrations (IC50s) for P-gp and BCRP were both 2 μM for itraconazole, 5 and 12 μM for hydroxyitraconazole, 3 and 6 μM for posaconazole, and 3 and 11 μM for isavuconazole, respectively. BSEP was strongly inhibited by itraconazole and hydroxyitraconazole (3 and 17 μM, respectively). Fluconazole and voriconazole did not inhibit any transport for >60%. Micafungin uniquely inhibited all transporters, with strong inhibition of MRP4 (4 μM). Anidulafungin and caspofungin showed strong inhibition of BCRP (7 and 6 μM, respectively). Amphotericin B only weakly inhibited BCRP-mediated transport (127 μM). Despite their wide range of DDIs, azole antifungals exhibit selective inhibition on efflux transporters. Although echinocandins display low potential for clinically relevant DDIs, they demonstrate potent in vitro inhibitory activity. This suggests that inhibition of ABC transporters plays a crucial role in the inexplicable (non-cytochrome P450-mediated) DDIs with antifungal drugs. 相似文献
68.
Ruslami R Aarnoutse RE Alisjahbana B van der Ven AJ van Crevel R 《Tropical medicine & international health : TM & IH》2010,15(11):1289-1299
Objectives To review the current knowledge about tuberculosis (TB) and diabetes, assessing the implication of the global increase of diabetes for TB control and patient care. Methods Systematic literature review. Results Using public databases, it can be estimated that 12.6% (95% CI 9.2–17.3%) of new TB cases in the 10 countries with the highest TB burden will be attributable to TB in 2030, a relative increase of 25.5% compared to 2010. Diabetes is associated with a higher age and body weight among patients with TB, but probably not with a specific clinical presentation of TB. Rifampicin hampers glycemic control by increasing the metabolism of most oral antidiabetic drugs, while diabetes patients may have lower concentrations of anti‐TB drugs. This might be one factor contributing to higher TB treatment failure rates. Conclusions The global epidemic of diabetes has implications for control and treatment of TB. Prospective studies are needed to improve prevention, early detection and treatment of concomitant diabetes and TB, especially in developing countries. 相似文献
69.
卒中是一种常见、严重的疾病,仅美国每年的新发病例就高达795000例,并已成为全世界人类死亡和残疾的主要病因。10年前,重组型组织纤溶酶原激活剂(recombinant tissue plasminogen activator,rt—PA)被批准用于治疗急性缺血性卒中。rt—PA应用指南建议,应在卒中发病后3h内静脉给予rt—PA,给药前应行头部CT检查,排除颅内出血。 相似文献
70.
急性缺血性卒中影像学检查的建议——美国心脏协会的科学声明(中) 总被引:1,自引:0,他引:1
2.3核磁共振血管成像(MRA)
2.3.1背景和方法:在头部MRI检查中常结合MRA,用于急性卒中患者病情评估以指导治疗决策的制定^[19]。日前,有几种不同的MRA技术用于脑血管成像,包括二维时间飞跃(timeof-flight,TOF)序列、三维TOF序列、 相似文献