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71.
超声心动图对62例房间隔缺损封堵术后心功能变化的评价 总被引:5,自引:0,他引:5
目的:应用超声心动图评价房间隔缺损(ASD)封堵术前后左、右心室功能的变化。方法:对62例成功施行经皮穿刺ASD封堵术的患者进行研究。所有患者在术前、术后1周及1个月分别进行超声心动图检查.观察心脏大小及功能的改变。结果:ASD封堵术后,左室舒张末期前后径、左室舒张末期容积、左室每搏量及左室射血分数增大,而左室收缩末期容积未见明显改变;右室舒张末期前后径、右室舒张末期容积、右室收缩末期容积、右室每搏量、右室射血分数及右室心肌工作指数均减小。结论:经皮穿刺ASD封堵治疗既可减轻右室容量负荷,改善右室功能,也可改善左室的收缩功能:超声心动图对ASD封堵前后心脏血流动力学评价及疗效的观察起了重要的作用。 相似文献
72.
E Baracca C Longhini S Aggio C Brunazzi A E Aubert R Pansini 《European heart journal》1991,12(2):249-261
The present study applies a non-invasive method to the quantitative evaluation of left ventricular stiffness in normal subjects and in patients with ischaemic heart disease (IHD). We have studied 20 patients with IHD and 25 healthy subjects. The third heart sound (S3) was detectable in all patients. We have correlated the energy spectrum of S3, divided into 15 Hz bands, with a series of echocardiographic parameters. The existence of a significant correlation between the spectrum energy and the diameter and thickness of the left ventricle at the moment of S3 allowed us to explore the possibility of interpreting the origin of S3 based on a mathematical model. Our hypothesis has been that, once the left ventricle starts vibrating, it behaves as a simple physical model composed of a mass and an elastic element. To this purely elastic model one can add a factor accounting for viscosity, with a damping effect, to obtain a more complex viscoelastic model. The stiffness coefficient 'k' was computed in both models from the peak frequency of S3 and the left ventricular mass at the moment of S3. Furthermore, in the viscoelastic model, the damping element 'c' was also computed. Both parameters--k and c--were significantly increased in the group with IHD compared with the control group. Although a simplification of the vibrating system, these models make it possible to obtain non-invasively information on the characteristics of the left ventricle through the combined use of echocardiography and spectral analysis of S3. 相似文献
73.
A M Heyse D Vanhercke J Nimmegeers L Missault R Claeys G Hollanders L Versée 《European journal of echocardiography》2003,4(4):334-335
We describe the case of a 79-year-old woman with mitral insufficiency and a double-orifice mitral valve (DOMV), discovered by echocardiography. Transthoracic echocardiography showed two insufficiency jets. Transesophageal echocardiography revealed a DOMV. Each orifice was provided with a subvalvular apparatus. No associated congenital abnormalities were present. Our case demonstrates that even in elderly patients with a double regurgitant jet, DOMV should be suspected and assessed by transesophageal echocardiography. 相似文献
74.
NAVIN C. NANDA M.D. SAYED MOHAMMED ABD-EL RAHMAN M.D. GAJENDRA KHATRI M.D. GOPAL AGRAWAL M.D. ADEL A. EL-SAYED M.D. HASSAN A. SHEHATA HASSANIAN M.D. MOHAMMAD KAMRAN M.D. JAMES KIRKLIN M.D. DAVID C. McGIFFIN M.D. WILLIAM L. HOLMAN M.D. ALBERT D. PACIFICO M.D. 《Echocardiography (Mount Kisco, N.Y.)》1995,12(6):619-628
In the present study, we compared three-dimensionally (3-D) reconstructed images with multiplane two-dimensional (2-D) transesophageal echocardiographic (TEE) images in 17 patients with various cardiac masses and defects. To overcome the problem of making measurements from 3-D reconstructed images, we carefully "dissected" the 3-D dataset using paraplane and anyplane 2-D sections, which were then used to obtain the maximum sizes of the cardiac masses and defects. Of the 15 vegetations and 9 abscesses detected by 3-D TEE in 7 patients, only 8 (53%) vegetations and 4 (44%) abscesses were detected by multiplane 2-D TEE (P < 0.02). Also, the exact anatomical location, shape, geometry, and extent of various cardiac masses and defects were more clearly delineated by 3-D than 2-D TEE. The maximum dimensions of cardiac masses and defects were larger by 3-D than by 2-D TEE in 17 (89%) of the 19 lesions available for comparison (P < 0.002). In addition, 3-D TEE correlated more closely than 2-D TEE when compared to surgical measurements in three patients in whom they were available. Thus, it would appear that in several instances, the exact size of the cardiac lesion could only be assessed by analysis of the 3-D volumetric dataset. Out preliminary study has demonstrated the superiority of transesophageal 3-D reconstruction over multiplane 2-D TEE in both qualitative and quantitative assessment of various cardiac mass lesions and pathological defects. 相似文献
75.
76.
应用超声心动图监测,经导管关闭先天性心脏间隔缺损9例。术中监测的主要内容有:(1)确定关闭器在心内的位置;(2)显示残余分流和瓣膜返流;(3)观察房间隔缺损球囊探测的过程。结果表明:超声心动图在显示心内结构、关闭器位置,残余分流和瓣膜流等方面有其独特性,同时可结合声学造影或术中需要进行多方面的监测。 相似文献
77.
失去肝动脉血液供应后大鼠肝门部胆管周围血管丛变化的三维构像研究 总被引:2,自引:0,他引:2
目的 探讨完全失去肝动脉血液供应后,大鼠肝门部胆管周围血管丛(PBP)的形态学变化。方法 将SD大鼠随机分为两组,对照组仅游离胆总管、门静脉、腔静脉和肝总动脉,不做切断;实验组结扎肝动脉,并切断肝十二指肠韧带除门静脉以外的其它组织,阻断其它侧支血管对肝门部胆管的血液供应。术后应用计算机对大鼠肝门部组织切片进行PBP三维可视化构建,并对PBP内层微血管进行定量分析,对胆管壁组织进行病理学检查。结果 实验组肝门部胆管分叉部位PBP平面结构显示胆管扩张,胆管壁明显增厚,壁内微血管尖细,排列紊乱,内层微血管密度减低;PBP立体构像显示空间结构紊乱,不规则,微血管细小,管壁不均匀增厚。与对照组相比,实验组肝门部PBP内层微血管总数明显减少(P〈0.01),肝门部PBP内层微动脉数也明显减少(P〈0.05)。实验组肝门部胆管壁呈慢性增生性炎症改变。结论 失去含氧量高的动脉血液供应时,PBP形态结构将会发生一系列改变,胆管壁组织也将发生相应的病理变化。 相似文献
78.
一种新的正交参数选优法及其在非线性回归分析中的应用 总被引:2,自引:0,他引:2
非线性回归分析是工程中经常采用的一种用来估计数学模型参数的方法,该方法能否顺利运用与参数初始值的选择有极大关系。本研究提出一种新的正交参数选优法——阻尼正交表法,它不仅可以保证非线性回归分析算法的顺利收敛,而且能够显著提高后者的收敛速度,进而极大改善非线性回归分析算法的应用性能。本研究的数值试验及心肌造影超声心动图定量分析应用实例表明,作为对传统正交参数选优法的一种改进,阻尼正交表法在科学与工程计算或信号与信息处理领域有着很好的应用前景。 相似文献
79.
Imad Sheiban M. D. Dino Casarotto Giampaolo Trevi Paolo Benussi Alberto Marini Roberto Accardi Antonio Motta Massimo Brunelli Claudio Muneretto Alessandro Tenuti Ludovico Antonio Scuro 《Cardiovascular and interventional radiology》1987,10(3):157-161
The accuracy of two-dimensional echocardiography in the detection of intracardiac masses was verified in 334 patients who
underwent cardiac catheterization in our laboratory over 21 consecutive months. A complete two-dimensional echocardiographic
(2DE) examination was performed a day before catheterization. The presence or absence of a mass was verified at surgery in
77 patients who successively underwent mitral or aortic valve replacement (51), left ventricular aneurysmectomy with or without
myocardial revascularization (25), and resection of atrial myxoma (2). In 32 patients 2DE revealed the presence of a mass-left
or right atrial thrombi in 12, left atrial myxoma in 2, left ventricular thrombi in 16, and endocardial vegetations in 2.
The other 45 patients were free of intracardiac masses on 2DE. Anatomic verification at surgery revealed the presence of an
intracardiac mass in 34 patients. In 30 (true positives) of these, 2DE revealed the mass as well, and in 4 (false negatives)
the presence of a mass had not been identified by 2DE. In 2 patients (false positives) the predicted mass was not found at
surgery. Absence of a mass was correctly predicted by 2DE in 41 patients (true negatives). Thus 2DE detected intracardiac
masses with sensitivity of 88.2% and a specificity of 95.3%. We recommend that 2DE be performed in all patients prior to hemodynamic
study and/or cardiac surgery to enable safer management of patients with intracardiac masses during cardiac catheterization
and/or cardiac surgery. 相似文献
80.
PICANO E.; MARRACCINI P.; Lattanzi F.; Levantesi D.; Masini M.; Vacche M.Dalle; DlSTANTE A.; 'ABBATE A. 《European heart journal》1987,8(1):38-44
Twenty-four patients with a history of effort angina, a positiveexercise stress test (EST) and coronary artery disease wereenrolled in the study; 12 patientshada positive dipyridamole-echocardiographytest (DET) and 12 had a negative DET. Each patient performeda total of 4 ESTs in the absence of therapy on two successivedays; for each test the rate-pressure product (RPP), an establishedindex of my ocardial oxygen demand, was measured at the onsetof ischaemia (ST depression >015mV) or at the peakof maximal exercise (if a repeated EST was negative). Taking into account the lowest of the 4 RPP values ( x 1/100)in each patient, there was no significant difference betweenDET-negatives and DET-positives (185.2±49.3 vs 157.4±32.4).Conversely, when considering the highest of the 4 RPP valuesin each patient, there was a significant difference betweenDET-negatives and DET-positives (280.3 ± 63.9 vs 183.3± 37.0; p < 0.01). Thus, DET may provide a clinically useful tool for assessingin the individual the organic ceiling of coronaryreserve, by eliminating the variability in coronary tone, whichmay affect EST reproducibility and the correct evaluation ofthe impairment of organic coronary reserve. 相似文献