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W Bocksch

Publications and source records attributed to W Bocksch.

24 records · Page 2Linked to original sources
PubMed1995

Intravascular ultrasound imaging in patients with acute myocardial infarction.

Myocardial infarction is the result of acute thrombotic occlusion of a coronary artery secondary to rupture of an atherosclerotic plaque. Intracoronary ultrasonic examinations (ICUS) were performed in patients with acute myocardial infarction in order to describe intraluminal ultrasonic findings at the site of an acute coronary occlusion. Coronary angiography and ICUS studies were performed consecutively within 6 h after the onset of chest pain in 50 patients with acute myocardial infarction (AMI) prior to percutaneous coronary angioplasty (PTCA). Following angiographic documentation of a proximal occlusion, a 3.5 mechanical ultrasound catheter (30 MHz) was advanced successfully through the lesion in 42 of 50 patients (84%). In 37 of the 42 patients (88.1%), ICUS differentiated between pulsatile, low echogenic, intraluminal material suggesting thrombus, and mural more highly echogenic atherosclerotic plaque. A negative imprint of the ICUS catheter was documented within the low echogenic material in 25 of 42 (60%) patients with AMI. Low echogenic intraluminal material was found in 31 of 42 (73.4%) segments proximal to the highly echogenic plaque and in 28 of 42 (66.7%) segments distal to it, indicating pre- and post-stenotic thrombus in AMI. The plaque appeared eccentric in 32 of 42 patients (76.2%) with AMI. Cross-sectional area stenosis due to highly echogenic plaque averaged 48 +/- 14%. Calcification of plaque was evident in 35 of 42 patients (83.3%) and the surface of the plaque was rough in 30 of 42 (42.4%). Fissures were found in 10 (23.8%) and a dissection was detected in four (9.5%) cases.

Adult↗
PubMed1994

Quantitative assessment of peripheral and coronary artery lesions before and after balloon angioplasty: a comparison of intravascular ultrasound and angiography.

Intravascular ultrasound and conventional angiography were used to determine the degree of stenosis before and after angioplasty in 25 consecutive patients with peripheral arterial occlusive disease and 15 selected patients with coronary artery disease. Angiographic determinations of the luminal area and percent stenosis were made with the help of an automatic detection system, and the same parameters were evaluated planimetrically in the ultrasound studies. Following angioplasty of peripheral lesions, angiography demonstrated a significantly greater increase in mean luminal area (10.8 +/- 7.8 mm2 vs 5.8 +/- 4.0 mm2; P < 0.05) and a greater reduction in degree of stenosis (26% +/- 16% vs 14% +/- 11%; P < 0.05) than did the ultrasonic investigation. There was a significant but moderate correlation between values for the luminal area determined by angiography and ultrasound before angioplasty (r = 0.75; SEE = 4.8 mm2) and in normal proximal segments of coronary arteries (r = 0.79; SEE 4.1 mm2). Following angioplasty there was no significant correlation between angiographic findings and those determined by intravascular ultrasound in peripheral or coronary lesions. These results suggest that angiography and intravascular ultrasound are fundamentally different imaging and analysis techniques. Following angioplasty, conventional angiography rarely demonstrated dissection or intraluminal filling defects, while intravascular ultrasound detected plaque rupture and the presence of intraluminal atheroma in almost all cases. Quantitative determinations of luminal area and degree of stenosis rely on indirect measures with conventional angiography, while these parameters are determined directly by intravascular ultrasound.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Stress echocardiography--an evaluation of current status].

Exercise echocardiography, a versatile, noninvasive diagnostic test of left ventricular wall motion performed at rest and under induced stress, enables the cardiologist to detect and assess coronary artery disease. Stress-induced ischemia is thereby expressed as left ventricular regional wall motion abnormality. By using various physical (bicycle or treadmill exercise) and pharmacological (dipyridamole, dobutamine, adenosine) stress inducers, the test provides information about the localization and extent of coronary artery disease in addition to detecting stress-induced coronary insufficiency. As regards diagnostic accuracy in detecting coronary artery disease, stress echocardiography is superior to exercise electrocardiography and, according to the available data, it is comparable to perfusion scintigraphic testing. Studies have demonstrated the clinical value of stress echocardiography in detecting residual stenosis after angioplasty, for diagnosing bypass dysfunction after heart surgery, for preoperative risk assessment in noncardiac surgeries, and for obtaining prognostic information, e.g., after myocardial infarction. Preliminary studies have shown that pharmacological exercise echocardiography is able to identify viable myocardium in the early phases after acute myocardial infarction. Furthermore, it is able to predict the functional success of revascularization in chronic regional left ventricular dysfunction. In addition to the wide range of diagnostic possibilities in coronary artery disease, other notable applications include stress testing for assessment of global left ventricular pump function in patients with aortic regurgitation or cardiomyopathy.

Adenosine↗
PubMed1993

[Stress echocardiography: evaluation of left ventricular function after administration of the transpulmonary echo contrast medium SHU 508 A].

Stress echocardiography has recently gained increased importance as a method for assessment of left ventricular function. However, suboptimal image quality in some patients may limit use of this technique. In the present study, 10 patients with moderate image quality in the resting echocardiograms (apical 4-chamberview) were reinvestigated after administration of the intravenous transpulmonary saccharide-based left heart contrast agent SHU 508 A. Duration of contrast enhancement in the left ventricle determined by visual assessment was 135 s (SEE +/- 39) at rest and 112 s (+/- 24) during maximum exercise. On a scale ranging from O (no contrast) to 4 (excessively strong contrast) enhancement averaged 2.5 at rest and during exercise. The left ventricle was divided into three segments (septum, apex, lateral wall) and delineation of the endocardial border was assessed. Detection of the border improved significantly after contrast administration, especially at the lateral wall. Despite better visual assessment of the endocardial border, there was no improvement in automatic or semi-automatic contour recognition. No clinically significant side-effects were observed. Three patients reported a sensation of warmth at the injection site. In conclusion, intravenous administration of SHU 508 A improves visual detection of the left ventricular endocardial border in patients with suboptimal image quality and helps to achieve acceptable diagnostic accuracy with stress echocardiography in these patients.

Aged↗