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81.
Two hundred and ten patients with clinical evidence of heartfailure, developing after an acute myocardial infarction, wererandomized to treatment with the ß1 antagonist metoprolol50100mg b.i.d. (n=106) or the ß1 partial agonistxamoterol 100200 mg bid. (n=104). Left ventricular systolicand diastolic function were assessed with echocardiography andtransmitral Doppler cardiography before and after 3 and 12 monthsof double-blind treatment. E-point septal separation and percent left ventricular fractional shortening were used as indicesof systolic function. The ratio between peak early and latemitral diastolic flow (E/A ratio) and isovolumic relaxationtime were used as indices of diastolic function. In the xamoterol group, there was a deterioration in E-pointseptal separation (P<0·05). A difference between thetreatment groups was present both at 3 months (E-point septalseparation 11·4 vs 13·0 mm, P<0·0l,fractional short ening 271 vs 252%, P<005) and 12 months(E-point septal separation Ill vs 13·2 mm, P<0·05fractional shortening 26·9 vs 25·0%, P<0·05).E/A ratio increased in the metoprolol group (P<0·05)but not in the xamoterol group. At 3 months there was a significantdifference (0·85 vs 0·67, P<0·005 betweenthe groups but not at 12 months. In comparison with the ß1-receptor antagonist metoprolol,the ß1 partial agonist xamoterol impaired left ventricularsystolic function in patients with clinical evidence of heartfailure after an acute myocardial infarction. 相似文献
82.
用电子计算机对核素、多普勒和心尖搏动图中的8项左室舒张功能指标进行判别分析,比较各指标与冠心病的密切程度。结果显示患者年龄和各项舒张功能指标明显不同于正常组。判别方程为:Z=0.21X_1+23.86X_2-22.88X_3-0.18X_4+2.83X_5+2.06X_6+66.86X_7+1.66X_8。临界值为42.99。判别正确率为100%。各指标的贡献率大小依次为EV/AV,1/3FF,A/E-O,PFR,DATI,EDC,IRT和1/3FFd。提示:多普勒EV/AV与冠心病的关系最为密切,核素的1/3FF次之,心尖搏动图的A/E~O亦是一个较好的指标。 相似文献
83.
应用ATL-ultramark超6型彩色多普勒超声诊断仪诊断扩张型心肌病100例,并与性别、年龄相应的正常人对比分析。结果:除扩张型心肌病各组室间隔及左室后壁舒张期厚度与相应正常对照组相比无显著性差异(P>0.05)外,其左室舒张内径及收缩内径、左房内径明显大于正常对照组(P<0.01),左室射血分数及左室内径缩短分数较正常对照组明显降低(P<0.01),并见心腔内血流速度缓慢,颜色变淡。另在77例病人中探及40例瓣膜返流。提示该诊断方法对扩张型心肌病具有直观、简便、准确、迅速的优点,为本病的诊断及鉴别诊断提供了良好的手段。 相似文献
84.
Christine Boutin John Dyck Lee Benson Christine Houde Robert M. Freedom 《Pediatric cardiology》1992,13(3):176-177
Summary Balloon atrial septostomy is an established method of palliation for several forms of congenital heart disease. Previously performed under fluoroscopic x-ray control, recent reports have demonstrated the utility of transthoracic echocardiographic monitoring. We report the first application of uniplane transesophageal echocardiography (TEE) (6.7-mm probe) as an alternative imaging modality for control of ballon atrial septostomy on neonates in the intensive care unit. 相似文献
85.
近年来,超声定量检查技术在临床的应用为心血管疾病患者的心功能评估提供了量化的依据,本文介绍了超声诊断仪的使用部分最新定量检查技术。 相似文献
86.
桂永浩 《中国超声医学杂志》1995,(12)
对20个16三体染色体异常小鼠胚胎进行了多普勒超声心动图研究。胎龄从10天至15天。9例发现流入道返流波型,6例发现流出道返流波型。120例染色体正常胚胎无一例发现返流波型。16三体小鼠模型作为先天性心脏病研究的理想模型,本文首次提供了对此类模型胚胎血液动力学研究的非创伤性监测方法。 相似文献
87.
目的:应用彩色多普勒超声心动图指导经皮二尖瓣球囊成形术(PBMV)治疗风湿性二尖瓣狭窄的价值、方法:运用彩超对行PBMV的患进行术前术后检查,观察二尖瓣钙化程度及部位、开口形状、瓣口面积、二尖瓣返流(MR)程度、瓣下病变、左房左室大小、左房有无血栓.结果:91例PBMV术后患中,术后MR72例,其中MR新出现19例,MR加重8例、与术前对比,术后二尖瓣开放幅度、二尖瓣口面积、二尖瓣跨瓣压、二尖瓣压差半降时间较术前有明显改善趋势,左房内径、肺动脉内径较术前有缩小趋势.同时,术后左房压、右室压及肺动脉压也有下降趋势。结论:彩超能明确PBMV治疗二尖瓣狭窄的效果。影响:PBMV效果的因素较多,但二尖瓣钙化的程度、部位和瓣膜形态较为重要。 相似文献
88.
C Minneci G Casolo G Popoff A Sulla C E Comin E Pedemonti 《European journal of echocardiography》2004,5(1):72-75
We report a patient with a mass originating from the anterior mitral valve leaflet causing severe left ventricular outflow tract obstruction. Noninvasive imaging provided the best diagnostic tools for diagnosis. Histological findings showed a very rare giant blood cyst of the mitral valve. 相似文献
89.
PETER T. BUSER M.D. MICHEL ZUBER M.D. PETER RICKENBACHER M.D. PAUL ERNE M.D. HANS-RUDOLF JENZER M.D. DIETER BURCKHARDT M.D. 《Echocardiography (Mount Kisco, N.Y.)》1997,14(6):597-605
To define the prevalence of cardioembolic sources found by transesophageal echocardiography (TEE) in different age groups of patients with and without cryptogenic systemic embolism, TEE risk factors for cardiogenic embolism were identified from 341 consecutive patients referred for TEE. One hundred and thirty-five had cryptogenic cerebral or systemic peripheral embolic events (CEE) and 206 other indications for TEE (CTR). Cardioembolic sources were found in 40% of CEE and in 29% of CTR (P < 0.02). Specifically, left atrial (LA) thrombi (P < 0.0001), atrial septal aneurysm with right-to-left shunt (P < 0.002), and atherosclerotic aortic plaques (P < 0.02) were more frequent. The prevalence of potential cardioembolic sources was significantly higher in patients ≥ 70-years old than in younger patients (P < 0.03), specifically LA thrombi (P < 0.004) and atherosclerotic aortic plaques (P < 0.0001). In patients ≥ 70-years old, potential cardioembolic sources were found in 63% and in 40% in CEE and CTR (P = 0.073), respectively. However, LA thrombi were more frequent in CEE (P < 0.003). Thus, potential cardioembolic sources observed by TEE are found more frequently in patients ≥ 70-years old than in younger patients. LA thrombi were more frequent in CEE than in CTR patients ≥ 70-years old. In patients ≥ 70-years old with CEE who are eligible for an anticoagulant regimen, a search for potential cardioembolic sources by TEE should be considered. 相似文献
90.
抗性家蝇蛹期多肽的双向电泳分析 总被引:5,自引:0,他引:5
分析抗性家蝇蛹期多肽,以了解蛋白质变化情况。方法:对家蝇的抗性株、对照株和敏感株蛹体内的多肽进行了聚丙烯酸胺凝胶电泳分析。结果:抗性株具有一特异的多肽点,且有3个多肽点在量上明显多于对照株。结论:杀虫剂的作用可使抗性家蝇体内的蛋白在质和量上发生改变。 相似文献