Biomedical subjects

M Haude

Publications and source records attributed to M Haude.

149 records · Page 9Linked to original sources

PubMed1985

[Qualitative evaluation of myocardial perfusion using digital subtraction angiocardiography].

The purpose of this study was to discover whether the passage of contrast medium through the myocardium can be visualized by digital subtraction angiocardiography and whether myocardial perfusion can be determined qualitatively from the difference images. Cineangiograms (duration 20 s) were obtained during routine coronary angiography and analyzed by means of a computerized image processing system. The results show that the passage of contrast medium through the coronary artery system, myocardium and coronary veins can be visualized. In 10 patients myocardial perfusion at rest was classified qualitatively into four categories (well perfused, slightly reduced perfusion, markedly reduced perfusion and perfusion defect) from local contrast intensity and the time dependent wash-in phase of the contrast medium. Intra- and interobserver comparison of the qualitative estimation of myocardial perfusion showed a close correlation (p less than 0.001 to p less than 0.0001). In the same 10 patients myocardial perfusion at rest was evaluated from Tl-201 scintiscans by two independent observers. A comparison between the qualitative classification of local myocardial perfusion assessed by both methods revealed a close correlation (p +/- 0.049). These results indicate that myocardial perfusion at rest can be visualized by digital image processing and evaluated qualitatively from cineangiograms.

Adult↗

PubMed1985

[Evaluation of myocardial perfusion based on digital subtraction angiocardiography measured contrast medium flow times].

The purpose of this study was to discover whether myocardial perfusion can be determined quantitatively by digital subtraction angiocardiography from the passage of contrast medium through the myocardium. Cineangiograms (duration 20 s) were obtained during routine coronary angiography and analyzed by means of a computerized image processing system. Regional myocardial contrast intensity was plotted versus time as a densogram for quantitative assessment. The parameter "medium rise time" showed a good reproducibility (r = 0.92). The average of medium rise time was 2.9 s in well-perfused areas, 3.7 s in less perfused areas, 5.2 s in areas with markedly reduced perfusion and 5.8 s for perfusion defects or scars using Tl-201 scintigrams as reference. The differences between the four groups were significant except between areas of markedly reduced perfusion and perfusion defects or scars (p less than 0.05). The correlation of medium rise time to the extent of the stenosis of the coronary vessel supplying the corresponding myocardial region revealed that the medium rise time on an average was 3.2 s distal to unstenosed vessels, 3.2 s distal to slightly stenosed vessels, 5.4 s distal to highly stenosed vessels and 4.7 s distal to vessel occlusion. The differences between the groups were not significant except between the groups of patients with low and high-grade coronary stenoses. These results indicate that the parameter "medium rise time" of the intensity-time curves determined by digital image processing provides a quantitative assessment of myocardial perfusion from cineangiograms.

Adult↗

PubMedDate not supplied

Cefotaxime versus penicillin in the late stage of Lyme disease--prospective, randomized therapeutic study.

The low responsiveness of Lyme arthritis to high dose intravenous penicillin G therapy has evoked the demand for new drugs for the treatment of late stage borreliosis. As can be deduced from in vitro susceptibility data, third generation cephalosporins are far more effective on Borrelia burgdorferi spirochetes than penicillin G. The study presented here was designed to compare cefotaxime at a dosage of 2 x 3 g/day with penicillin G at a dosage of 2 x 10 megaunits/day, for ten days in a prospective randomized trial. A total of 135 patients were included in the study. They were diagnosed to suffer from late stage Lyme borreliosis on the basis of defined clinical symptoms compatible with stage three borreliosis manifestations of at least six months' duration and positive antibody titers against B. burgdorferi. Final outcomes were recorded after a 24 month post-treatment observation period with re-examination at three-month-intervals. Cefotaxime proved to be significantly superior to penicillin G with 87.9% versus 61.3% of treatments resulting in full or incomplete remission of symptoms (p = 0.002). Clinical remission was accompanied by declining antibody titers. Herxheimer-like reactions were observed in 20% of the patients of the penicillin group and in 40.5% of the patients of the cefotaxime group and may be interpreted as an indication of a response to therapy.

Adolescent↗

PubMedDate not supplied

Tomographic left ventricular volume determination in the presence of aneurysm by three-dimensional echocardiographic imaging. I: Asymmetric model hearts.

To improve the accuracy of measurements of left ventricular volume in the presence of an aneurysm, we used three-dimensional echocardiographic imaging to analyze the shape of left ventricles in 23 asymmetric model hearts with eccentric aneurysms of different sizes, shapes, and localizations. A standard 3.75 MHz ultrasound probe with a rotation motor device was used to obtain a three-dimensional data set. By rotating the probe stepwise 1 degree, 180 radial ultrasound pictures were digitized. On the basis of the three-dimensional data set, the following parameters were determined and compared with the dimensions of the model hearts obtained by direct measurement: total left ventricular volume (LVV), aneurysm volume, area of the aneurysm's base, the longest aneurysm long diameter, and the longest aneurysm cross diameter. In addition, quantification of LVV by three-dimensional echocardiography was compared with biplane two-dimensional echocardiographic measurement according to the disk method. Good agreements were found for LVV measured by both techniques, three-dimensional echocardiographic and direct measurement (mean of differences = 0.91 ml; SD of differences = +/- 6.23 ml; line of regression y = 1.07 x - 14.24 ml; r = 0.968; standard error of the estimate [SEE] = +/- 6.17 ml), aneurysm volume (mean of differences = 0.43 ml; SD of differences = +/- 2.14 ml; line of regression y = 1.05 x - 0.81 ml; r = 0.996; SEE = +/- 1.96 ml), area of the aneurysm's base (mean of differences = 0.24 cm2; SD of differences = +/- 1.72 cm2; line of regression y = 1.02 x - 0.02 cm2; r = 0.981; SEE = +/- 1.75 cm2), the longest aneurysm long diameter (mean of differences = -0.26 mm; SD of differences = +/- 1.60 mm; line of regression y = 0.97 x + 1.34 mm; r = 0.996; SEE = +/- 1.54 mm), and the longest aneurysm cross diameter (mean of differences = 1.35 mm; SD of differences = +/- 3.94 mm; line of regression y = 0.95 x + 3.17 mm; r = 0.941; SEE = +/- 3.99 mm). In contrast, in these extremely asymmetric-shaped model hearts, agreement between biplane two-dimensional echocardiographic and both direct LVV measurement (mean of differences = 7.8 ml; SD of differences = +/- 20.8 ml; line of regression y = 1.48 x - 92.45 ml; r = 0.874; SEE = +/- 18.36 ml) and three-dimensional echocardiographic measurements (mean of differences = -7.6 ml; SD of difference = +/- 18.1 ml; line of regression y = 0.59 x + 80.98 ml; r = 0.908; SEE = +/- 10.36 ml) was poor. Thus tomographic three-dimensional echocardiography allowed accurate volume determination of asymmetric model hearts in the shape of left ventricles with eccentric aneurysms.

Cardiac Volume↗

PubMedDate not supplied

Coronary microembolization.

Atherosclerotic plaque rupture is a key event in the pathogenesis of acute coronary syndromes and during coronary interventions. Atherosclerotic plaque rupture does not always result in complete thrombotic occlusion of the entire epicardial coronary artery with subsequent acute myocardial infarction; however, in milder forms it may result in the embolization of atherosclerotic and thrombotic debris into the coronary microcirculation. The present report summarizes the available morphologic evidence for coronary microembolization in patients who died of coronary artery disease, especially sudden death. The report then goes on to address the experimental pathophysiology of coronary microembolization in animal models of acute coronary syndromes and heart failure. Finally, the report presents the available clinical evidence for coronary microembolization, highlights its key features--arrhythmias, contractile dysfunction, infarctlets and reduced coronary reserve--and addresses prevention by mechanical protection devices and glycoprotein IIb/IIIa antagonism.

Animals↗