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81.
目的:胸片显示上肺血管扩张对诊断左心衰竭的意义,文献报导较少,而临床多见此征象。研究该征象的病理基础及产生原因,可提高对左心衰的早期认识。方法:收集近几年确诊、资料较全的35例各种疾病所致左心衰病例,观察胸片并测量上肺血管宽度,进行综合分析。结果:35例(冠心病6例、高血压性心脏病14例,肺源性心脏病合并左心衰4例;充血性心肌病及病毒性心肌炎11例)均有上肺血管扩张表现。上肺血管宽43~67mm,平均51mm。12例左侧位上肺静脉均较上肺动脉宽1倍以上。部分胸片伴有肺淤血及肺间质水肿。结论:上肺血管扩张可作为左心衰的一项诊断依据。 相似文献
82.
目的:研究可否用左室重量表达并判定左心功能不全的可能性。方法:将左心功能不全按NYHA标准分成4个级别,每级1组,并设正常对照组,用超声心动图测量同一个病人的左室射血分数(LVEF)和左室重量。用SAS统计软件做方差分析。结果:LVEF与左心功能不全高度负相关(R=-0.77270),左室重量与左心功能不全高度正相关(R=0.73421)。LVEF、左室重量各级指标间差别显著(n=153,F=64.85,P<0.01;n=153,F=53.39,P<0.0001)。各级与对照组比统,LVEF指标从Ⅱ级开始方有显著差别(P<0.05);而左室重量指标从Ⅰ级开始就有显著差别(P<0.05)。结论:LVEF与左室重量指标均与左心功能不全高度相关,但心功能Ⅰ级的病人,左室重量指标更为敏感。 相似文献
83.
目的:利用间接指标的方法,观察急性心肌梗塞(AMI)后心肌再灌注损伤(MyocardialReperfusionInjury,MRI)的临床表现,了解MRI对左室射血功能及梗塞后心绞痛的影响。方法:对尿激酶静脉溶栓后32例冠脉再通者和10例冠脉未再通者进行心电图和心肌酶学动态监测,AMI后3周所有患者接受心脏彩超检查。结果:临床判断冠脉再通者中MRI发生率为5625%(18/32),心电图主要表现为突发短暂性ST段明显抬高,其次是再灌注心律失常,束支或房室传导阻滞最少见。MRI时血清CPK峰值时间为1386±426小时,较冠脉再通而无MRI组1917±536小时显著前移(P<005)。MRI组LVEF(4525±1077%)显著高于冠脉未再通组(3860±925%)(P<005),但与无MRI组(5328±1277%)相比,P>005。MRI组梗塞后心绞痛发生率为2728%,与无MRI组4280%和冠脉未再通组1000%相比,P均>005。结论:AMI静脉溶栓后部分患者发生再灌注损伤,MRI对LVEF和梗塞后心绞痛发作无显著影响。 相似文献
84.
目的:探讨左半结肠急性梗阻如何安全实施一期切除吻合术。方法:回顾分析左半结肠急性梗阻行一期切除吻合术33例。结果:一期愈合31例,吻合口瘘1例,死亡率1例。结论:左半结肠急性梗阻只要正确掌握一期切除吻合术适应症,以及完善术中术后处理,可以安全施行一期切除吻合术。 相似文献
85.
Studies on plasma endothelin changes in varicocele patients 总被引:1,自引:0,他引:1
Aim: To investigate the possible role endothelin may play in the pathogenesis of varicocele and varicocele-induced infer-tility. Methods: In varicocele patients, radioimmunoassay is used to determine the blood endothelin concentration inthe spermatic vein and the antecubital vein separately. Results: The blood endothelin concentration of the spermaticvein (66.8±23.5 pg/mL) was significantly higher (P <0.05) than that of the antecubital vein (55.3±25.3 pg/mL).The endothelin concentration in the spermatic vein in Grade Ⅱ varicocele patients was not significantly different from thatin Grade Ⅲ patients ( P = 0.87). Conclusion: The higher blood endothelin level in the spermatic vein may indicate theinvolvement of endothelin in the pathophysiology of varicocele and varicocele-induced infertility. (Asian J Androl 1999Sep ; 1: 159 - 160) 相似文献
86.
The case of a 17-year-old male patient with severe end-stage dilated cardiomyopathy and a large thrombus formation within the cavum of the left ventricle is reported. After an acute thrombectomia combined with a partial left ventriculectomy (Batista procedure), the patient was successfully treated with an appropriate left ventricular assist device (LVAD) system using a centrifugal nonocclusive pump (Biomedicus, Medtronic, Anaheim, CA, U.S.A.). Mechanical support was removed on Day 9, and the patient was discharged from the hospital on Day 19. The effectiveness of emergency mechanical support in patients with very unfavorable prognoses is discussed. 相似文献
87.
纪震 《中国医疗器械杂志》1999,23(5):252-257
提出基于自适应方向滤波方法来提取左心室轮廓。在噪声的干扰下,引入经平滑处理的方向滤波能够得到精确的边缘,所获得的边缘方向矢量能够在边缘跟踪时对边缘走向预测,同时对参数进行自适应地调整。通过尽量少的人机交互,算法能够自动提取出左心室的轮廓。实验证明该算法增加了边缘提取的精度和一致性,同时显著地降低了计算复杂度。 相似文献
88.
BACKGROUND: Recent studies have shown that left ventricular geometric adaptationto hypertension is complex. The spectrum of geometric adaptationsin a general population and its relationship to systolic anddiastolic function has, however, not been investigated. OBJECTIVES AND METHODS: This echocardiographic and Doppler study investigated the relationshipsbetween left ventricular geometric shape (normal, concentricremodelling, concentric hypertrophy and eccentric hypertrophy)and left ventricular systolic and diastolic function in a populationsample of 584 males aged 70 in Uppsala, Sweden. The influencesof hypertension, coronary heart disease and diabetes mellituswere also evaluated. RESULTS: Sixteen percent of the healthy population (n=167) demonstratedthe presence of left ventricular hypertrophy (mainly eccentric).Subjects with hypertension (n=115) showed an increased leftventricular mass (eccentric left ventricular hypertrophy 31%,concentric left ventricular hypertrophy 15%), when comparedwith healthy subjects (P<0.001). Subjects with coronary heartdisease (n=32) without hypertension also showed an increasedleft ventricular mass (most often eccentric) (P<0.05). UsingDoppler determinations of cardiac index, no differences werefound in cardiac index between the geometric groups. Raisedtotal peripheral resistance, increased blood pressure and enlargedleft atrium were found in both concentric and eccentric leftventricular hypertrophy (P<0.010.05). Disturbed diastolicfunction was seen with a prolongation of the isovolumic relaxationtime in eccentric (P<0.01) and increased atrial-dependentleft ventricular filling in concentric left ventricular hypertrophy(P<0.05). CONCLUSIONS: Alterations in left ventricular geometry were common in thispopulation-based study of elderly males, both in healthy subjectsand in subjects with hypertension or coronary heart disease.Raised total peripheral resistance and left ventricular diastolicdysfunction were common findings in both concentric and eccentricleft ventricular hypertrophy. 相似文献
89.
Constantinos Anagnostopoulos Mark G. Gunning Dudley J. Pennell Robin Laney Haralambos Proukakis S. Richard Underwood 《European journal of nuclear medicine and molecular imaging》1996,23(8):909-916
We have validated ECG-gated emission tomography using technetium-99m methoxyisobutylisonitrile for the assessment of regional ventricular function by comparing it with cine magnetic resonance imaging (MRI). Gated tomography was performed at rest in 24 patients referred for myocardial perfusion imaging [17 males and seven females with a mean age of 58 years, nine of whom had had a previous myocardial infarction (MI)]. Scores were assigned to each of nine myocardial segments for wall motion and for thickening. Cine MRI was analysed in an identical fashion. Four out of 216 (2%) segments were uninterpretable by gated tomography because of inadequate tracer uptake. In eight patients without coronary artery disease (CAD), wall motion and thickening were normal by both methods. Gated tomography showed abnormal wall motion or thickening in all patients with previous MI and in five of seven patients with CAD but no prior MI. Association between wall motion and thickening was good (r
s=0.86). Overall, there was good agreement between gated tomography and MRI for both wall motion (178/212 segments, =0.66) and wall thickening (184/212 segments, =0.69). In segments with severely reduced perfusion, however, there was poorer agreement (=0.31). Interobserver and intraobserver agreement was high ( from 0.61 to 0.78). Thus, in patients investigated for CAD, there is good overall agreement between gated tomography and MRI but the agreement is lower in segments with severe perfusion defects. 相似文献
90.
Michael Gottsauner-Wolf Johanna Schedimayer-Duit Gerold Porenta Marianne Gwechenberger Kurt Huber Dietmar Giogar Peter Probst Heinz Sochor 《European journal of nuclear medicine and molecular imaging》1996,23(12):1613-1618
Measurement of global left ventricular function is important in the follow-up of cardiac patients and is a good prognostic indicator in acute cardiac situations. We compared quantitative measurements of global left ventricular function made with radionuclide angiography (RNA) and contrast cardiac ventriculography (CVG) to visual semiquantitative estimates from two-dimensional echocardiographic images (2D-echo). Three hundred and thirty-nine consecutive patients who underwent RNA were assessed with 2D-echo within 3 months. In addition, 92 of these patients also underwent CVG (correlation of ejection fraction between CVG and RNA:r=0.82;P<0.0001). The RNA mean ejection fractions in the four 2D-echo groups (0=normal, 1=slightly, 2=moderate, or 3=severe reduced left ventricular function) differed markedly (P<0.0001); however, there was overlapping among the groups (2D-echo score/RNA ejection fraction: 0=57.3%±12.8%; 1=46.0%±12.9%; 2=29.6%±12.2%; and 3=24.6%±11.5%) and the difference between 2D-echo scores 2 and 3 was not significant. 2D-echo showed a good concordance in RNA classes (0=505; 1=35%–49%; 2=21%–34%; and 3=520% ejection fraction) 0 (133/166; 80%) and 3 (18/30; 60%) but low concordance in classes 1 (27/82; 33%) and 2 (21/61; 34%). For accurate assessment of global left ventricular ejection fraction, visual semiquantitative judgement of a 2D echocardiographic image is limited in comparison to CVG or RNA, especially in patients with a slight or moderate reduction in left ventricular ejection fraction. 相似文献