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11.
12.
Seventy-eight consecutive survivors of a first acute anteriorQ wave myocardial infarction (AMI) underwent two-dimensionalechocardiography (2D echo), colour Doppler echo and radionuclideangiography (RNA) for the diagnosis of left ventricular (LV)anteroapical aneurysm, in order to study the relationship ofthis complication to precordial ST segment elevation in thesepatients. The ST elevation (mm) in lead V2, the maximum ST elevationin V1-V6 and the sum of ST elevation in V1 to V6 were calculated.LV aneurysm was present in 19 patients by 2D echo, of whom 12had a paradoxical systolic flow pattern (red and outward towardsthe transducer) at the apex. There was no difference between the mean ST elevation in V2or the maximum ST elevation in V1-V6 in patients with and withoutan aneurysm, although the sum of ST elevations in V1 to V6 washigher in the former group (P<0.01). ST elevation of patientswith and without paradoxical systolic flow also did not differsignificantly. Wall motion abnormality (akinesis and dyskinesis)by 2D echo in the anterior wall was seen in 74% of patientswith and 36% of patients without an aneurysm (P<0.005), andin the septal region in 63% and 47% of respective patients (P-NS).There was no difference between the magnitude of ST elevationin subgroups of patients with ejection fraction (EF) 30% to40%, but the mean EF of patients with (23 ± 2.1%) andwithout a LV aneurysm (34 ± 1.3%) differed (P<0.001). It is concluded that precordial ST segment elevation does notclearly and in the diagnosis of an anteroapical LV aneurysm.It is related to akinesis and dyskinesis in anterior and septalregions inherent in patients with AMI and does not indicateimpaired LV function. 相似文献
13.
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
14.
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
15.
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
16.
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
17.
Left ovaries of bursectomized chick embryos were examined on the 17th day of incubation in comparison to normal and sham-operated controls, by histological and histochemical observations. The results show that in bursectomized embryos the cortex appears irregulary developed, with a significant decrease in the mean thickness and in the percentage of the secondary sex cords in the total cortical area. Furthermore, the germinal epithelium appears thicker and the subcortical medulla and the tunica albuginea more compact. The greater activity of the enzyme
5–3-hydroxysteroid dehydrogenase (
53HSD) found in ovaries of bursectomized embryos (histochemical method) could be related to an endocrine dismetabolism affecting the cortical development. On the basis of these results and those of other authors, some hypotheses are advanced. In particular, an action of the bursal factor on GTH receptors could be the factor responsible of the enhanced steroidogenic activity altering the hormonal environment. 相似文献
18.
Murakami T Kikugawa D Endou K Fukuhiro Y Ishida A Morita I Masaki H Inada H Fujiwara T 《Artificial organs》2000,24(12):953-958
In this study, we analyzed the extent and pattern of regression of left ventricular (LV) hypertrophy after aortic valve replacement in patients with aortic stenosis (AS) and compared the results with those of another group of patients with aortic regurgitation (AR). Seventy patients who underwent isolated aortic valve replacement were divided into 2 groups. Group 1 was comprised of 29 patients who underwent aortic valve replacement for aortic stenosis, and Group 2 of 41 patients who underwent aortic valve replacement for aortic regurgitation. A third group of 10 healthy subjects served as a healthy control group. Echocardiographic studies were done before the operation and 5 years postoperatively. At follow-up, a significant reduction in the left ventricular mass was found in both groups, but it remained significantly greater than in the healthy control group. The ratio of LV wall thickness to radius (th/r) in Group 1 decreased significantly, and at follow-up it was within the normal value. In Group 2, the th/r ratio increased, and at follow-up it was within the normal value. After aortic valve replacement, the wall thickness remained significantly greater than normal for patients with AS, and the chamber radius remained significantly greater than normal for patients with AR. For these reasons, LV hypertrophy still existed in both groups at postoperative follow-up. The actuarial survival rate was 85.3% at 16 years for Group 1 and 83.4% at 18 years for Group 2. There was no significant difference in the long-term survival rates between the 2 groups. Actuarial freedom from valve-related events was 91.9% at 16 years for Group 1 and 82% at 18 years for Group 2. There was no significant difference in the valve-related event free curves between groups. After 5 years of follow-up, th/r reached normal for both groups, indicating remodeling of the LV geometry after aortic valve replacement. 相似文献
19.
Transarterial left ventricular assist devices (LVADs), such as the Hemopump, IABP, and PUCA-pump, are meant to be introduced into the body via the femoral or axillary artery without major surgery. For certain applications, introduction is performed directly into the aorta via an open thorax procedure. A prototype of a vascular access device has been realized that allows direct access into the aorta as an alternative for the common surgical graft anastomosis suturing technique. The device consists of a metal tube acting as a circular knife to cut a hole in the aortic wall, a screw to store the removed part of the aortic wall, and a plastic tube that is introduced through the hole and tightly connected to the aortic wall. The device could be placed without aortic clamping. The device has been tested on a slaughterhouse porcine aorta. A low-pressurized aorta appeared to be the worst case; thus, two animal experiments in the low-pressurized pulmonary artery were performed. No leakage occurred for pressures between 40 and 300 mm Hg. 相似文献
20.
Assessment of adolescent varicocele 总被引:4,自引:0,他引:4
Varicocele is the most important male factor responsible for decreased fertility potential in married couples. From March through June 1994, 2,470 school boys aged 10–20 years were examined to establish the incidence of consecutive grades of varicocele and to develop a protocol for diagnosis and treatment of adolescents with varicocele. Grade 1 varicocele was found in 18%, grade 2 in 12%, and grade 3 in 5% of the population examined. An original protocol of ultrasonographic (US) examination (previously verified by angioscintigraphy) was introduced to assess boys with clinically diagnosed varicocele. The volume of each testis, testicular volume decrease (TVD), pampiniform vein diameter (PVD), and basal (BBF) and maximum blood flow (MBF) velocities were measured in 625 boys. In 74 cases a semen analysis was performed. The statistical analysis revealed that the presence of venous reflux and PVD correlated with the grade of varicocele. Decreases in testicular volume were highly dependent on the grade of varicocele, PVD, and BBF and MBF velocities. Analysis of the relationship between spermatic (boys over 17 years) and US findings revealed that the quality of spermatogenesis can be predicted by US examination in adolescents with varicocele. The authors recommend multiparametric US examination as a reliable, objective, and repeatable technique for establishing criteria for operative treatment in boys under 18 years of age with varicocele as well as for postoperative evaluation. 相似文献