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1.
Ngai-Yin Chan Chi-Chung Choy Ho-Chuen Yuen Hoi-Fan Chow Ho-Fai Fong 《The Canadian journal of cardiology》2019,35(4):396-404
Background
Persistent iatrogenic atrial septal defect (iASD) is a common but poorly characterized complication after cryoballoon (CB) pulmonary vein isolation (PVI) procedures. We therefore investigate its prevalence, evolution, risk factors, and clinical outcomes in a prospective longitudinal study.Methods
A total of 108 patients (41 women, mean age 57 ± 11.3) underwent CB PVI for AF. Serial transesophageal echocardiography (TEE) was performed 9 months and then annually until 6 years after the procedure to study the characteristics of persistent iASD.Results
Persistent iASD occurred in 33 (30.6%) patients 9 months after CB PVI. Spontaneous closure of iASD was found in 6 (22.2%) and 3 (15.8%) patients 2 and 3 years after the procedures, respectively. No spontaneous closure was observed on 4, 5, and 6-year TEE follow-up. The projected long-term persistence rate of iASD after CB PVI was therefore 20% (30.6% × 0.778 × 0.842). Using multivariate logistic regression, a higher number of cryoapplications (≥ 2 minutes) was the only independent predictor of persistent iASD 9 months after CB PVI (odds ratio [OR] 1.207; 95% confidence interval [CI], 1.033-1.411, P = 0.018). Two (1.9%) patients with significantly larger iASD size than the others (long diameter 12.6 ± 0.8 vs 3.7 ± 1.5 mm, P < 0.001; short diameter 10.9 ± 0.2 vs 3 ± 1.1 mm, P < 0.001) required percutaneous closure because of exertional dyspnea and right ventricular enlargement. Over 129.7 patient-years follow-up, during which iASD persisted, there was no occurrence of neurologic events.Conclusions
Approximately one fifth of patients undergoing CB PVI will have permanently persistent iASD. Patients with defect sizes of greater than 10 mm may need percutaneous closure due to significant left-to-right shunting. 相似文献2.
《The Journal of thoracic and cardiovascular surgery》2023,165(1):149-158.e4
BackgroundCoronary artery bypass grafting (CABG) improves survival in patients with heart failure and severely reduced left ventricular systolic function (LVEF). Limited data exist regarding adverse cardiovascular event rates after CABG in patients with heart failure with midrange ejection fraction (HFmrEF; LVEF > 40% and < 55%).MethodsWe analyzed data on isolated CABG patients from the Veterans Affairs national database (2010-2019). We stratified patients into control (normal LVEF and no heart failure), HFmrEF, and heart failure with reduced LVEF (HFrEF) groups. We compared all-cause mortality and heart failure hospitalization rates between groups with a Cox model and recurrent events analysis, respectively.ResultsIn 6533 veterans, HFmrEF and HFrEF was present in 1715 (26.3%) and 566 (8.6%) respectively; the control group had 4252 (65.1%) patients. HFrEF patients were more likely to have diabetes mellitus (59%), insulin therapy (36%), and previous myocardial infarction (31%). Anemia was more prevalent in patients with HFrEF (49%) as was a lower serum albumin (mean, 3.6 mg/dL). Compared with the control group, a higher risk of death was observed in the HFmrEF (hazard ratio [HR], 1.3 [1.2-1.5)] and HFrEF (HR, 1.5 [1.2-1.7]) groups. HFmrEF patients had the higher risk of myocardial infarction (subdistribution HR, 1.2 [1-1.6]; P = .04). Risk of heart failure hospitalization was higher in patients with HFmrEF (HR, 4.1 [3.5-4.7]) and patients with HFrEF (HR, 7.2 [6.2-8.5]).ConclusionsHeart failure with midrange ejection fraction negatively affects survival after CABG. These patients also experience higher rates myocardial infarction and heart failure hospitalization. 相似文献
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5.
Fast CT-PRESS-based spiral chemical shift imaging at 3 Tesla. 总被引:2,自引:0,他引:2
Dirk Mayer Dong-Hyun Kim Elfar Adalsteinsson Daniel M Spielman 《Magnetic resonance in medicine》2006,55(5):974-978
A new sequence is presented that combines constant-time point-resolved spectroscopy (CT-PRESS) with fast spiral chemical shift imaging. It allows the acquisition of multivoxel spectra without line splitting with a minimum total measurement time of less than 5 min for a field of view of 24 cm and a nominal 1.5x1.5-cm2 in-plane resolution. Measurements were performed with 17 CS encoding steps in t1 (Deltat1=12.8 ms) and an average echo time of 151 ms, which was determined by simulating the CT-PRESS experiment for the spin systems of glutamate (Glu) and myo-inositol (mI). Signals from N-acetyl-aspartate, total creatine, choline-containing compounds (Cho), Glu, and mI were detected in a healthy volunteer with no or only minor baseline distortions within 14 min on a 3 T MR scanner. 相似文献
6.
鸡抗内毒素卵黄抗体IgY的制备 总被引:2,自引:1,他引:1
目的:研究分别应用内毒素(LPS)、类脂A(LipidA)和大肠杆菌突变株15免疫鸡后其蛋黄中抗内毒素抗体IgY的产量、纯度、效价并筛选最佳免疫抗原。方法:分别应用内毒素(LPS)、类脂A(LipidA)和大肠杆菌J5突变株作为抗原免疫25周龄Leghom鸡,水溶法(WD)提取蛋黄中抗体IgY,双紫外光测定抗体含量,SDS-PSGE电泳检测抗体纯度,细胞酶联染色和ELISA检测抗体特异性、效价及筛选最佳免疫抗原。结果:3种抗内毒素IgY含量和效价分别为14.4mg/ml和1:12 800(J5)、10.61mg/ml和1:12 800(LPS)、9.26mg/ml和1:3200(LipidA),抗体纯度均为95%左右。结论:大肠杆菌突变株J5和内毒素(LPS)为最佳免疫抗原,免疫鸡后其蛋黄中抗内毒素抗体IgY的产量和效价最高。 相似文献
7.
神经干细胞移植治疗缺氧缺血性脑损伤的实验研究 总被引:23,自引:4,他引:19
目的 研究神经干细胞移植治疗缺氧缺血性脑损伤的可行性。方法 取孕龄为12-16天的母鼠,从胎脑中分离神经细胞,进行培养、鉴定。用出生7天的SD大鼠的新生鼠制作缺氧缺血性脑损伤的动物模型,7天后接受神经干细胞移植(移植组,n=16只),同时设置对照组,只注射磷酸缓冲液(对照组,n=8只),8-10周后,作Y迷宫实验检测大鼠的学习能力和记忆能力。取脑组织作免疫组织化学检查。结果 从大鼠胎脑中成功培养出神经干细胞,培养条件下呈悬浮状态生长,形成神经球,绝大多数的细胞表达神经干细胞的标志物神经巢蛋白(nestin)。接爱神经干细胞移植组大鼠的学习能力、记忆能力和对照组相比,有明显提高,差异具有显著性(P<0.05)。接受神经干细胞移植大鼠组织中可见存活的移植细胞,并和宿主脑组织融合在一起。结论 在体外培养条件下,可从胎脑组织中培养出神经干细胞,移植到缺氧缺血性脑损伤大鼠脑内后,细胞与宿主的脑组织融合在一起,动物的学习、记忆能力有改善。移植神经干细胞是治疗缺氧缺知性脑损伤的有效方法之一。 相似文献
8.
Medial epicondylitis is a chronic noninflammatory condition resulting from mechanical injury. Despite many treatment options,
including rest, medications, physiotherapy and operative interventions, the results are too often poor; thus new treatment
options are sought. We treated 4 men with chronic epicondylitis (5 affected joints) with extracorporeal shock wave therapy
after failed attempts of other treatments. The patients’ complaints were graded with the Nirschl scoring system prior to and
six months after therapy. The treatment consisted of three sessions, at 20-day intervals, of 3000 pulses of ultrasonic shock
waves from a Piezolith 3000 unit (energy dosage was gradually increased to reach step 10 equaling 0.9 mJ/mm2). At the 6-month follow-up, no patient was pain free. Three cases had slightly lower Nirschl scores than prior to the procedure
but the patients rated this difference as insignificant; two cases were unchanged. No complications were observed but all
patients rated the procedure as very unpleasant. The well recognized biologic effects of ultrasonographic waves (heat generation,
oscillations, cavitation, etc.) that result in functional and structural changes of cellular membranes with sonochemical reactions
(acceleration of normal metabolism, oxygenation and reduction in water solutions, polymer degradation, etc.), even if present
in our cases, did not result in a noticeable decrease of symptoms, even though we used high energy and more impulses per session.
Significant variations in methodology make inconclusive the results of numerous reports on the use of extracorporeal shock
waves in epicondylar degenerative problems, although ineffectiveness of such therapy is the conclusion of a review by Haake
and colleagues. 相似文献
9.
降纤酶对进展性缺血性脑卒中预防作用的探讨 总被引:9,自引:7,他引:2
目的探讨降纤酶对进展性缺血性脑卒中的预防作用.方法将起病在72 h内的203例脑梗塞患者随机分成降纤酶治疗组及常规治疗组.降纤酶组在常规治疗的基础上加用降纤酶,治疗前后检测血液流变学各项指标,同时对进展性缺血性脑卒中患者的神经功能缺损进行评分.结果降纤酶组10例发生进展性缺血性脑卒中,常规治疗组24例,两组比较有显著性差异(P<0.05);降纤酶组发生的进展性脑卒中的进展的严重程度比常规治疗组轻(P<0.01);近期预后较常规治疗组好(P<0.05);降纤酶治疗能明显降低血液流变学各项指标.结论降纤酶治疗能降低进展性缺血性脑卒中发生率,有利于进展性缺血性脑卒中患者神经功能的恢复. 相似文献
10.