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91.
QT dispersion and myocardial viability in patients after acute myocardial infarction 总被引:18,自引:0,他引:18
BACKGROUND: In recent years QT dispersion (QTd) in post-infarct patients was estimated in many studies, but still little is known about its association with the presence of dysfunctional but viable myocardium. AIM: We investigated the relation between dispersion of QT interval and myocardial viability in patients after acute myocardial infarction (AMI). MATERIAL AND METHODS: In 52 patients (mean age 67.2+/-11.7) treated thrombolytically because of AMI 12-lead ECG and low dose-high dose dobutamine echocardiography was performed on 14th day after treatment. QTd and regional myocardial contractility were estimated three times: at baseline, low dose dobutamine (LDD) (10-15 microg/kg per min) and high dose dobutamine (HDD) infusion (up to 40 microg/kg per min). RESULTS: Patients with viable myocardium had lower baseline QTd than patients with only necrosis in infarct zone. Significant increase in QTd was shown during LDD and HDD both in patients with and without myocardial viability. During infusion of HDD QTd was significantly higher in patients with myocardial ischemia. The greatest percentage increase of QTd at HDD was shown in patients with biphasic response to dobutamine infusion i.e. with myocardial viability evidenced at LDD and myocardial ischemia at HDD. CONCLUSION: Patients with preserved myocardial viability had lower QTd values compared to those with similar left ventricular dysfunction but caused only by post-infarction necrosis. Ischemia evoked on 14th day after AMI was accompanied by greater increase in QTd in patients with myocardial viability in infarct region than in patients without. It may be one of the reasons of greater risk of serious ventricular arrhythmias in such patients during myocardial ischemia. 相似文献
92.
93.
Tomasz Zdrojewski Bogdan Wyrzykowski Lukasz Wierucki Tomasz Grodzicki Andrzej Januszewicz Krzysztof Narkiewicz Marzena Zarzeczna-Baran Jerzy Gluszek Grzegorz Opolski Witold Zatonski Andrzej Tykarski Wojciech Drygas 《European journal of cardiovascular prevention and rehabilitation》2006,13(5):832-838
AIM: Epidemiological data show that citizens of small towns and villages have presented worse trends in cardiovascular mortality during the political, social and economic transformation in Poland during past 15 years than citizens of large towns. To try to eliminate these inequalities the Polish 400 Cities Project (P400CP), a large educational and interventional project, was prepared. The project consists of two arms: medical and social interventions. MATERIAL AND METHODS: The main aim of the medical screening intervention in P400CP is to increase detection and control of cardiovascular risk factors in inhabitants of 418 small cities (<8000 inhabitants) and surrounding villages, particularly in men and people of lower education. In 2003 and 2004 the P400CP covered 123 cities. All together, 36 696 subjects aged between 18 and 98 years were examined. In all participants, blood pressure (BP), anthropometric measurements, laboratory tests and questionnaire interviews were performed. The social arm of P400CP is one of multi-level educational intervention. Modern techniques of social psychology and marketing were involved to increase participation in interventions. RESULTS: Only 12.5% of all subjects had normal BP, cholesterol (<190 mg/dl) and glucose (<100 mg/dl in whole capillary blood) levels. During the first screening visit 65.5% of all examined subjects had BP>/=140 mmHg or >/=90 mmHg. The fasting glucose level was increased in 19% of women and 26% of men. Almost two-third of all subjects had a total cholesterol level above the norm. CONCLUSIONS: The prevalence of cardiovascular risk factors in participants of the screening programme P400CP in small towns in Poland was very high. High prevalence and low control of risk factors in participants of the P400CP confirm the decision to target this programme at citizens of small towns and villages. 相似文献
94.
Gruchala M Ciećwierz D Wasag B Targoński R Dubaniewicz W Nowak A Sobiczewski W Ochman K Romanowski P Limon J Rynkiewicz A 《American heart journal》2003,145(1):125-131
Background There is growing evidence from recent studies that atrial natriuretic peptide (ANP) plays an important part in coronary blood flow regulation and in atherosclerosis. Transition T2238→C in the atrial natriuretic peptide (ANP) precursor gene, which leads potentially to the translation of ANP with 2 additional arginines, has been suggested to be associated with salt-sensitive hypertension. According to our knowledge, this study is the first to look for the potential association of the ScaI ANP gene polymorphism with the history of nonfatal myocardial infarction and the extent of coronary artery disease (CAD).Methods The study was performed in 847 consecutive, white patients (719 men and 128 women) with significant coronary artery stenosis confirmed by means of elective coronary angiography (at least 1 coronary artery with ≥50% lumen narrowing). Screening for the T2238→C substitution was performed by means of polymerase chain reaction of genomic DNA, followed by ScaI digestion and agarose gel electrophoresis.Results We found a significant association of the A2A2 ScaI ANP genotype with a higher incidence of positive history of nonfatal myocardial infarction (odds ratio 1.85, 95% CI 1.33-2.58) and multiple-vessel CAD (odds ratio 1.45, 95% CI 1.02-2.06). The ScaI ANP genotype distribution did not differ with age, sex, body mass index, plasma lipids, hypertension, diabetes mellitus, and family history of CAD in studied groups.Conclusions Our results suggest that the ScaI ANP polymorphism may be associated with nonfatal myocardial infarction and the extent of CAD. However, the precise mechanism of this association remains to be determined. (Am Heart J 2003;145:125-31.) 相似文献
95.
Kränkel N Katare RG Siragusa M Barcelos LS Campagnolo P Mangialardi G Fortunato O Spinetti G Tran N Zacharowski K Wojakowski W Mroz I Herman A Manning Fox JE MacDonald PE Schanstra JP Bascands JL Ascione R Angelini G Emanueli C Madeddu P 《Circulation research》2008,103(11):1335-1343
Reduced migratory function of circulating angiogenic progenitor cells (CPCs) has been associated with impaired neovascularization in patients with cardiovascular disease (CVD). Previous findings underline the role of the kallikrein-kinin system in angiogenesis. We now demonstrate the involvement of the kinin B2 receptor (B(2)R) in the recruitment of CPCs to sites of ischemia and in their proangiogenic action. In healthy subjects, B(2)R was abundantly present on CD133(+) and CD34(+) CPCs as well as cultured endothelial progenitor cells (EPCs) derived from blood mononuclear cells (MNCs), whereas kinin B1 receptor expression was barely detectable. In transwell migration assays, bradykinin (BK) exerts a potent chemoattractant activity on CD133(+) and CD34(+) CPCs and EPCs via a B(2)R/phosphoinositide 3-kinase/eNOS-mediated mechanism. Migration toward BK was able to attract an MNC subpopulation enriched in CPCs with in vitro proangiogenic activity, as assessed by Matrigel assay. CPCs from cardiovascular disease patients showed low B(2)R levels and decreased migratory capacity toward BK. When injected systemically into wild-type mice with unilateral limb ischemia, bone marrow MNCs from syngenic B(2)R-deficient mice resulted in reduced homing of sca-1(+) and cKit(+)flk1(+) progenitors to ischemic muscles, impaired reparative neovascularization, and delayed perfusion recovery as compared with wild-type MNCs. Similarly, blockade of the B(2)R by systemic administration of icatibant prevented the beneficial effect of bone marrow MNC transplantation. BK-induced migration represents a novel mechanism mediating homing of circulating angiogenic progenitors. Reduction of BK sensitivity in progenitor cells from cardiovascular disease patients might contribute to impaired neovascularization after ischemic complications. 相似文献
96.
Tyler F. Beck Philippe M. Campeau Shalini N. Jhangiani Tomasz Gambin Alexander H. Li Reem Abo‐Zahrah Valerie K. Jordan Andres Hernandez‐Garcia Wojciech K. Wiszniewski Donna Muzny Richard A. Gibbs Eric Boerwinkle James R. Lupski Brendan Lee Willie Reardon Daryl A. Scott 《American journal of medical genetics. Part A》2015,167(4):831-836
97.
Antonio Bayés de Luna MD PhD Wojciech Zareba MD PhD Miquel Fiol MD PhD Kjell Nikus MD PhD Yochai Birnbaum MD PhD Rafael Baranowski MD PhD Diego Goldwasser MD Paul Kligfield MD PhD Ryszard Piotrowicz MD PhD Günter Breithardt MD PhD Hein Wellens MD PhD 《Annals of noninvasive electrocardiology》2014,19(5):426-441
98.
Piotr Kukla M.D. Ph.D. Adrian Baranchuk M.D. Ph.D. Marek Jastrzębski M.D. Ph.D. Leszek Bryniarski M.D. Ph.D. 《Annals of noninvasive electrocardiology》2014,19(6):601-603
A 72‐year‐old man with heart failure, left ventricular dysfunction (ejection fraction 20%), prior ischemic stroke, COPD, and exacerbation of chronic renal failure was admitted in our unit. Serum potassium was 6.1 mmol/L, calcium concentration was at the lower normal range 2.15 mmol/L, and NT‐pro‐BNP was 28,900 pg/mL. The surface 12‐lead electrocardiogram (ECG) showed sinus rhythm at 60 bpm, PR interval 160 ms, QRS duration 115 ms, QT interval 460 ms, and left ventricular hypertrophy criteria. Negative T waves in leads I, II, aVL, and V4–V6 were also seen. In leads V4–V6, negative U waves were observed in concordance with negative T waves. In all precordial leads, beat‐to‐beat U‐wave polarity variability was observed as a polarity variation from negative to positive with associated and stable negative T waves, in a beat‐to‐beat alternate morphology. 相似文献
99.
Yochai Birnbaum Miguel Fiol Kjell Nikus Javier Garcia Niebla Ljuba Bacharova Sergio Dubner Wojciech Zareba Peter W. Macfarlane Antonio Luiz Ribeiro Iwona Cygankiewicz Antoni Bayes de Luna 《Annals of noninvasive electrocardiology》2020,25(5)
The Fourth Universal Definition of Myocardial Infarction (FUDMI) focuses on the distinction between nonischemic myocardial injury and myocardial infarction (MI), along with the role of cardiovascular magnetic resonance, in order to define the etiology of myocardial injury. As a consequence, there is less emphasis on updating the parts of the definition concerning the electrocardiographic (ECG) changes related to MI. Evidence of myocardial ischemia is a prerequisite for the diagnosis of MI, and the ECG is the main available tool for (a) detecting acute ischemia, (b) triage, and (c) risk stratification upon presentation. This review focuses on multiple aspects of ECG interpretation that we firmly believe should be considered for incorporation in any future update to the Universal Definition of MI. 相似文献
100.
Natalia Ziętara Marcin Łyszkiewicz Andreas Krueger Siegfried Weiss 《European journal of immunology》2014,44(1):23-32
An appropriate immune response against a specific pathogen requires finely orchestrated interactions between the various cell populations within the immune system. At the same time, immunological tolerance to self must be maintained. DCs play an essential role in achieving these dual requisites. They coordinate adaptive immunity by integrating signals directly emanating from both infectious agents and cells of the immune system. Many such signals, especially those from innate cells and T cells, have been extensively characterized. In contrast, little is known about how B cells modulate function of DCs. B cells produce a variety of cytokines, including IL‐10 and IL‐6, which are known to influence DC function. In addition, Igs constitute the major secretory products of terminally differentiated B cells (plasma cells). DCs express various types of receptors for binding Ig, such as Fc receptors and C‐type lectin receptors. In accordance, Igs can regulate DC function depending on the receptors engaged. Here, we review the emerging immunomodulatory role of cytokines and Ig secreted by B cells. We discuss the evidence for how these B‐cell‐derived factors may shape the adaptive immune response by directly acting on DCs. 相似文献