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911.
912.
目的:探讨肺静脉口弧形指数与心房颤动(房颤)导管消融术后复发的关系。方法:选取2008年2月至2011年3月在我院接受导管消融术的房颤患者120例,所有患者于术前3日内利用多排CT行左心房及肺静脉造影,并进行图像的三维重建。测量每条肺静脉前后径及上下径,并计算弧形指数(肺静脉前后径/肺静脉上下径)以描述肺静脉口形态。行射频消融治疗的房颤病人全部达消融终点,术后随访超过3个月,根据患者房性快速性心律失常(房颤、房扑或房速)的发生情况,将其分为治愈组和复发组,进行统计分析。结果:由弧形指数分析,四支肺静脉开口形态存在统计学差异(P0.05);房颤消融术后,53例病人复发。房颤消融术后复发患者的LIPV弧形指数与治愈者不同,差异有显著性(P0.05);两组患者的左上肺静脉(Left Superior Pulmonary Vein,LSPV),右上肺静脉(Right Superior Pulmonary Vein,RSPV),右肺下静脉(Right Inferior Pulmonary Vein,RIPV),的弧形指数比较差异不明显(P0.05)。结论:左下肺静脉形态的不一致性与房颤导管消融术复发有关。 相似文献
913.
《IRBM》2014,35(4):182-188
ObjectivesInfarct size is a major surrogate marker for prognosis in the context of myocardial infarction. There is a growing interest in validating a quantitative assessment approach in order to: (1) standardize these analyses; (2) to precise the individual prognosis of our patients. Several methods are available and were tested across their capacity to predict left ventricular (LV) remodeling at three months.Patients and methodsLate gadolinium enhancement-MRI was performed on day 5 and after a period of three months in 92 patients with STEMI. LV volumes and scar parameters were assessed visually (by using a four scale score) and quantitatively on day 5 and at three months. Dichotomous thresholds were defined first visually (VISUAL), then by 2, 5 and 6 standard deviations above remote myocardium, and by the full-width at half-maximum (FWHM) method.ResultsAll infarct sizing methods showed great relation to LV remodeling at three months (ROC analysis). Univariate predictors of an LV end-systolic volume index (LVESVi) superior to 70 mL/m2 were: heart failure, creatin kinase peak and infarct size at day 5. FWHM was shown to be the best of all quantitative methods. An infarct size superior to 44 grams predicted a LVESVi > 70 mL/m2 with a sensitivity of 90% and a specificity of 92.5%. FWHM reproducibility was good (r = 0.895, P < 0.0001, Bland Altman bias of 0.8 g).ConclusionIn the context of STEMI, FWHM is a tough and reproducible algorithm to quantitatively assess late gadolinium hyperenhancement, greatly related to functional prognosis at three months follow-up. 相似文献
914.
915.
Bean LJ Allen EG Tinker SW Hollis ND Locke AE Druschel C Hobbs CA O'Leary L Romitti PA Royle MH Torfs CP Dooley KJ Freeman SB Sherman SL 《Birth defects research. Part A, Clinical and molecular teratology》2011,91(10):885-893
BACKGROUND: Maternal folic acid supplementation has been associated with a reduced risk for neural tube defects and may be associated with a reduced risk for congenital heart defects and other birth defects. Individuals with Down syndrome are at high risk for congenital heart defects and have been shown to have abnormal folate metabolism. METHODS: As part of the population‐based case‐control National Down Syndrome Project, 1011 mothers of infants with Down syndrome reported their use of supplements containing folic acid. These data were used to determine whether a lack of periconceptional maternal folic acid supplementation is associated with congenital heart defects in Down syndrome. We used logistic regression to test the relationship between maternal folic acid supplementation and the frequency of specific heart defects correcting for maternal race or ethnicity, proband sex, maternal use of alcohol and cigarettes, and maternal age at conception. RESULTS: Lack of maternal folic acid supplementation was more frequent among infants with Down syndrome and atrioventricular septal defects (odds ratio [OR], 1.69; 95% confidence interval [CI], 1.08–2.63; p = 0.011) or atrial septal defects (OR, 1.69; 95% CI, 1.11–2.58; p = 0.007) than among infants with Down syndrome and no heart defect. Preliminary evidence suggests that the patterns of association differ by race or ethnicity and sex of the proband. There was no statistically significant association with ventricular septal defects (OR, 1.26; 95% CI, 0.85–1.87; p = 0.124). CONCLUSIONS: Our results suggest that lack of maternal folic acid supplementation is associated with septal defects in infants with Down syndrome. Birth Defects Research (Part A), 2011. © 2011 Wiley‐Liss, Inc. 相似文献
916.
917.
Zhang S Sun A Ma H Yao K Zhou N Shen L Zhang C Zou Y Ge J 《Journal of cellular and molecular medicine》2011,15(10):2245-2261
Optimal timing of cell therapy for myocardial infarction (MI) appears during 5 to 14 days after the infarction. However, the potential mechanism requires further investigation. This work aimed to verify the hypothesis that myocardial stiffness within a propitious time frame might provide a most beneficial physical condition for cell lineage specification in favour of cardiac repair. Serum vascular endothelial growth factor (VEGF) levels and myocardial stiffness of MI mice were consecutively detected. Isolated bone marrow mononuclear cells (BMMNCs) were injected into infarction zone at distinct time-points and cardiac function were measured 2 months after infarction. Polyacrylamide gel substrates with varied stiffness were used to mechanically mimic the infarcted myocardium. BMMNCs were plated on the flexible culture substrates under different concentrations of VEGF. Endothelial progenitor lineage commitment of BMMNCs was verified by immunofluorescent technique and flow cytometry. Our results demonstrated that the optimal timing in terms of improvement of cardiac function occurred during 7 to 14 days after MI, which was consistent with maximized capillary density at this time domains, but not with peak VEGF concentration. Percentage of double-positive cells for DiI-labelled acetylated low-density lipoprotein uptake and fluorescein isothiocyanate (FITC)-UEA-1 (ulex europaeus agglutinin I lectin) binding had no significant differences among the tissue-like stiffness in high concentration VEGF. With the decrease of VEGF concentration, the benefit of 42 kPa stiffness, corresponding to infarcted myocardium at days 7 to 14, gradually occurred and peaked when it was removed from culture medium. Likewise, combined expressions of VEGFR2(+) , CD133(+) and CD45(-) remained the highest level on 42 kPa substrate in conditions of lower concentration VEGF. In conclusion, the optimal efficacy of BMMNCs therapy at 7 to 14 days after MI might result from non-VEGF dependent angiogenesis, and myocardial stiffness at this time domains was more suitable for endothelial progenitor lineage specification of BMMNCs. The results here highlight the need for greater attention to mechanical microenvironments in cell culture and cell therapy. 相似文献
918.
Patricia Chakur Brum Daria Mochly‐Rosen 《Journal of cellular and molecular medicine》2011,15(8):1769-1777
Protein kinase C βII (PKCβII) levels increase in the myocardium of patients with end‐stage heart failure (HF). Also targeted overexpression of PKCβII in the myocardium of mice leads to dilated cardiomyopathy associated with inflammation, fibrosis and myocardial dysfunction. These reports suggest a deleterious role of PKCβII in HF development. Using a post‐myocardial infarction (MI) model of HF in rats, we determined the benefit of chronic inhibition of PKCβII on the progression of HF over a period of 6 weeks after the onset of symptoms and the cellular basis for these effects. Four weeks after MI, rats with HF signs that were treated for 6 weeks with the PKCβII selective inhibitor (βIIV5‐3 conjugated to TAT47–57 carrier peptide) (3 mg/kg/day) showed improved fractional shortening (from 21% to 35%) compared to control (TAT47–57 carrier peptide alone). Formalin‐fixed mid‐ventricle tissue sections stained with picrosirius red, haematoxylin and eosin and toluidine blue dyes exhibited a 150% decrease in collagen deposition, a two‐fold decrease in inflammation and a 30% reduction in mast cell degranulation, respectively, in rat hearts treated with the selective PKCβII inhibitor. Further, a 90% decrease in active TGFβ1 and a significant reduction in SMAD2/3 phosphorylation indicated that the selective inhibition of PKCβII attenuates cardiac remodelling mediated by the TGF‐SMAD signalling pathway. Therefore, sustained selective inhibition of PKCβII in a post‐MI HF rat model improves cardiac function and is associated with inhibition of pathological myocardial remodelling. 相似文献
919.
920.
目的:探讨经皮冠脉介入(PCI)治疗的急性心肌梗死(AMI)患者行早期康复训练后的疗效与安全性。方法:192例AMI患者经PCI治疗后随机分为康复组与对照组各96例,分别予早期心脏程序康复训练与传统康复治疗。比较2组患者的心脏结构、并发症及住院时间。结果:在住院期间及随访1年后,两组患者左室舒张末内径、左室收缩末内径、左室后壁厚度及左室射血分数无统计学差异(P>0.05);心律失常、心绞痛及死亡率等并发症均无显著性差异(P>0.05);而对照组院内感染发生率明显多于康复组(P<0.05)。结论:AMI患者PCI术后行早期心脏程序康复训练安全、有益,可明显减少院内感染的发病率,缩短住院时间。 相似文献