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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Six hundred and twenty-five patients with diabetes mellitus were studied by standardised clinical methods, resting and exercise electrocardiography (ECG) and digitised echocardiography to determine the prevalence of coronary and non-coronary heart disease. Clinical evidence of coronary artery disease (angina and infarction) was present in 110 (18 per cent) normotensive patients. Hypertension (blood pressure greater than 165/95 mmHg) was present in 172 (27 per cent) of whom 32 had cardiac symptoms. Heart failure or left ventricular dilatation was seen in 18 of whom 11 had either hypertension or coronary artery disease and six asymptomatic patients had unexplained ventricular hypertrophy. Echocardiograms in 245 of 290 asymptomatic patients with normal ECG showed that relaxation was prolonged (p less than 0.001) and mitral valve opening delayed (p less than 0.001) from normal especially in those with severe microangiopathy (proliferative retinopathy and/or heavy proteinuria). The peak rates of cavity dimension increase and posterior wall thinning were reduced from normal (both p less than 0.001) and patients with severe microangiopathy had the most marked changes. Redivision of these 245 diabetics by abnormalities of left ventricular function showed that 147 had normal function in whom only one of 23 (random 15 per cent sample) had a positive exercise ECG. Prolonged relaxation or delayed mitral valve opening alone (a nonspecific abnormality) was present in 41 and only three of 28 had a positive exercise ECG. Thirty-one had delayed mitral valve opening with inco-ordinate relaxation (abnormalities very suggestive of coronary artery disease) of whom 20 of 29 had a positive exercise ECG. Twenty-six had delayed mitral valve opening with slow cavity dimension increase or wall thinning (without hypertrophy) of whom 21 of 25 had a negative exercise ECG. This is a relatively specific abnormality similar to that found in left ventricular hypertrophy. Coronary artery disease is common in symptomatic and asymptomatic forms in diabetes mellitus. Non-coronary left ventricular diseases, such as dilation and hypertrophy, are probably no more common in diabetics than non-diabetics. A small number of diabetics with severe microangiopathy had abnormal relaxation and reduced peak rate of dimension increase or wall thinning which may represent left ventricular disease due to microangiopathy.
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PMID:A prospective study of heart disease in diabetes mellitus. 670 23

The left ventricular diastolic pressure-volume relationship shifts upward during angina, but why this happens is not known. To assess regional myocardial stiffness, we studied 12 patients who had coronary artery disease using simultaneous left ventricular micromanometer pressure recording and M-mode echocardiography before and during angina induced by pacing tachycardia. All patients had two- or three-vessel coronary artery disease that involved the posterior left ventricular wall circulation and had positive pacing stress tests, i.e., development of angina and a postpacing rise in left ventricular end-diastolic pressure (15 +/- 3 to 31 +/- 6 mm Hg, p less than 0.001). A marked upward shift in the relationship between the diastolic left ventricular pressure and the posterior wall thickness (h) occurred after pacing tachycardia, but the change in left ventricular posterior wall end-diastolic thickness was minimal (8.9 +/- 2.1 to 9.2 +/- 2.1 mm, NS). After pacing, the peak rate of left ventricular posterior wall thinning decreased (82 +/- 37 to 48 +/- 27 mm/sec, p less than 0.005) and the time constant of relaxation derived from the best exponential fit to the isovolumic left ventricular pressure decay increased (49 +/- 5 to 58 +/- 7 msec, p less than 0.001). Diastolic active left ventricular pressure decay, extrapolated from the exponential fit, was subtracted from the measured left ventricular pressure (which is equal in magnitude but opposite in sign to the radial stress at the endocardium) to calculate residual left ventricular pressure (PR) and hence residual stress (sigma R = -PR). A radial stiffness modulus (ER) was determined by the slope of the PR vs log h plots before and after pacing. Over the same range of residual radial stress (sigma R), ER was always higher during pacing-induced angina, indicating increased residual myocardial stiffness. Increased myocardial stiffness in addition to a decreased rate of wall thinning and slow active pressure decay contribute to the upward shift in left ventricular pressure-wall thickness and pressure-volume relationships during pacing-induced angina.
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PMID:Increased regional myocardial stiffness of the left ventricle during pacing-induced angina in man. 684 19

In order to study left ventricular diastolic function in diabetes mellitus, simultaneous echo- and phonocardiograms were recorded in 142 diabetics (free from heart disease), 20 normal subjects, and 16 patients with coronary artery disease. The resultant traces were digitised, and left ventricular relaxation and the rate and duration of cavity dimension increase and wall thinning were determined. Diastolic variables of left ventricular function were normal in 12 young diabetics with no complications. Significantly delayed mitral valve opening relative to minimum dimension and aortic valve closure was found in all other groups of diabetics. Forty-four diabetics with severe microvascular complications had significantly reduced peak rate and prolonged duration of wall thinning and dimension increase. The abnormalities were unlike those found in subjects with coronary artery disease. The extent of microvascular complications was significantly correlated to most variables of diastolic function. This relation was maintained in 31 diabetics with significant cavity dimension increase during isovolumic relaxation (incoordinate relaxation). In 42 juvenile onset patients there was good correlation between the duration of diabetes and most variables of diastolic function. These studies show that the primary cardiac abnormality in diabetic micro-angiography is a prolonged duration and reduced rate of posterior wall thinning with impaired left ventricular dimension increase, reflecting abnormal myocardial properties.
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PMID:Echocardiographic features of impaired ventricular function in diabetes mellitus. 707 4

The purpose of this study was to assess the sensitivity and specificity of two-dimensional echocardiography in detecting ischemia-induced transient myocardial dyskinesis. We prepared an open-chest dog model of severe coronary stenosis (90% reduction of circumflex coronary artery diameter) and induced ischemia by acutely raising myocardial oxygen requirements with i.v. isoproterenol and acute aortic constriction. The changes observed with echocardiography were compared with those obtained by intramyocardial sonomicrometers placed side by side or in an endocardial-epicardial orientation. Ischemia was defined as systolic wall expansion or thinning on sonomicrometers and two-dimensional echocardiography. We found complete agreement between sonomicrometers and two-dimensional echocardiography in all control tracings and after ischemia was induced; whenever dyskinesis occurred it was seen by both techniques. Although there was qualitative agreement between echocardiographic and sonomicrometric techniques, there were quantitative differences in the assessment of wall thickening. Such differences may be related to malalignment of the sonomicrometers, echocardiographic resolution limitations or other technical factors. We conclude that two-dimensional echocardiography is a sensitive and specific technique for detecting transient myocardial ischemia, and therefore should be useful for demonstrating exercise-induced ischemia in patients with coronary artery disease.
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PMID:Two-dimensional echocardiography in experimental coronary stenosis. I. Sensitivity and specificity in detecting transient myocardial dyskinesis: comparison with sonomicrometers. 709 70

Echocardiographic septal and posterior wall motion and thickness were measured in 55 subjects, of whom 20 patients with acute myocardial infarction, 20 with chronic coronary artery disease and 15 control subjects without evidence of cardiac disease. The results of the study that systolic thinning is indicative of an acute event. Abnormal changes in systolic wall thickening and wall motion occur commonly in patients with chronic coronary artery disease. Useful information about segmental wall motion abnormalities can be obtained from the echocardiogram when the areas involved can be visualized, but much of the ventricle is not routinely examined.
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PMID:Evaluation of segmental wall motion disturbances by echocardiography in ischemic heart disease. 726 82

Exercise thallium myocardial scintigrams were analyzed in 76 consecutive patients with documented normal coronary arteries to identify the factors associated with abnormal or "false positive" studies. The thallium scintigrams had been judged normal in 60 patients (79 percent) and abnormal in 16 (21 percent). Analysis of the location of thallium defects in the 16 patients with abnormal scintigrams revealed a pattern that was consistent with coronary artery disease in 5, including 4 with an abnormal left ventricle, and a pattern that was inconsistent in the other 11. In 9 of these 11 patients the pattern of defects suggested soft tissue attenuation, by the diaphragm in 2 and breast or adipose tissue in 7, whereas in the other 2 patients isolated apical defects were seen. Among exercise myocardial scintigrams performed in 68 randomly selected patients with abnormal coronary arteries, 6 (9 percent) were reported to be normal. In four patients with abnormal scintigrams, the diagnosis of coronary artery disease was based on an inconsistent pattern. In three of these the pattern was related to isolated apical defects and in one it was related to apparent soft tissue attenuation. "Consistent" scintigraphic defects, seen frequently in patients with normal coronary arteries, in whom they are usually associated with an abnormal left ventricle. In patients with normal coronary arteries, "inconsistent" thallium defects are probably related to soft tissue attenuation or to normal apical thinning. Although defects caused by isolated apical abnormalities and soft tissue attenuation are also seen in patients with coronary diseases and add somewhat to scintigraphic sensitivity, they are a rare cause of diagnostic scintigraphic abnormalities in patients with coronary disease. The incidence of false positive thallium scintigrams could be reduced and overall accuracy improved by careful attention to the pattern of thallium defects.
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PMID:The inconsistent pattern of thallium defects: a clue to the false positive perfusion scintigram. 727 Apr 32

Location of infarct lesions (IL) demonstrated by two-dimensional echocardiography (2DE) was correlated with electrocardiographic patterns of myocardial infarction and with the sites of obstructive lesions in the individual coronary arteries. The left ventricular wall was displayed by phased-array 2DE in 47 patients with healed myocardial infarction, 29 of whom underwent coronary arteriography. Segmental analysis of IL was performed on 14 segments, 10 of which were obtained by the parasternal short-axis recordings at the mitral (basal) and papillary muscle (mid) levels (each level containing the anterior septum, anterior wall, lateral wall, posterior wall, and posterior septum). The remaining 4 segments (septum, anterior wall, lateral wall, posterior wall) were obtained by the apical 2-chamber and 4-chamber recordings. IL were defined as akinesis, thinning, increased echo density, or absent systolic thickening of the left ventricular wall. All 22 patients with anterior infarction (Q in V1-V4) had IL in the mid anterior septum which was specific for the lesion of the left anterior descending artery (LAD). The presence or absence of the r wave in V1 could not predict the involvement of this segment. IL in the apical anterior wall and septum were observed in 21 of 22 patients. The presence of Q waves in V5, V6 suggested the additional involvement of the apical posterior wall. Additional Q waves in I, aVL indicated the extension of IL from the mild anterior septum to the basal anterior septum, anterior wall, and mid anterior wall. The basal and mid lateral walls appeared normal in most patients. This pattern of IL distribution was observed in 5 of 6 patients with a stenosis on the proximal LAD. All 14 patients with inferior infarction (Q in II, III, aVF) had IL in the mid posterior wall and posterior septum. In contrast, 5 patients with infero-posterior infarction (Q in II, III, aVF + R in V1) and 6 patients with posterior infarction (R in V1) had IL in the mid lateral as well as the mid posterior wall without an involvement of the posterior septum. Coronary arteriography revealed that all of the 10 patients with inferior infarction had a stenosis in the right coronary artery, whereas 6 patients with infero-posterior or posterior infarction invariably had a stenosis in the left circumflex coronary artery. It was concluded that 2DE provides a reliable method for detecting IL and anatomic location of myocardial infarction reflecting a specific coronary artery disease.
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PMID:[Two-dimensional echocardiographic approach to the localization of myocardial infarction: echocardiographic, electrocardiographic, and coronary arteriographic correlations (author's transl)]. 732 May 55

Under basal conditions the echocardiographic findings in anginal patients (pts.) without previous myocardial infarction appears usually normal. Consequently, the usefulness of the ultrasounds evaluation in angina pectoris has been commonly considered poor and the utilization of this technique in coronary artery disease has been restricted to the detection of myocardial infarction in its acute phase or to its chronic mechanical alterations. The purpose of this study was to assess the possibility offered by M-mode echocardiography to detect changes caused by transient myocardial ischemia at rest in man, in view of the possible diagnostic application of this technique. The reported results were obtained from 25 ischemic attacks (13 spontaneous and 12 ergonovine induced) with ST segment elevation or pseudonormalization of a basally negative T wave at rest. The semiautomatic computerized analysis of echocardiograms continuously recorded during these attacks showed a reduction of motion and of systolic thickening, accompanied by a diastolic thinning of the wall involved by the ischemia. These changes occur very early: they appear few seconds before ECG changes and are accompanied by a reduction of contraction and relaxation dP/dt and precede the onset of chest pain; moreover, they are followed by an increase in left ventricular internal diameters. In conclusion M-mode echocardiography is a sensitive technique capable to detect transient myocardial ischemia in the course of spontaneous or induced angina with ST segment elevation or positivity of negative T wave. This approach could be helpful in the diagnostic evaluation of patients with atypical chest pain and/or aspecific ECG changes and it can be complementary to other non invasive techniques such dynamic ECG and nuclear cardiology techniques.
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PMID:[Diagnosis of transient acute myocardial ischemia in man by M-mode echocardiography (author's transl)]. 732 34

It is not yet clear whether 99mTc-methoxyisobutyl-isonitrile (MIBI)-uptake is a reliable indicator of myocardial viability, and a threshold value, differentiating viable from scarred myocardium, in comparison to a morphological and functional standard of reference has not been defined. MIBI-uptake was quantified in 800 segments from 55 patients with angiographically proven coronary artery disease with and without a history of myocardial infarction. Viable myocardium was defined from gradient-echo magnetic resonance images (MRI) as regions with systolic wall thickening or an end-diastolic wall thickness above the mean value -2.5 SD of a healthy control group (n = 21). Scar was defined as end-diastolic wall thickness > 2.5 SD below the normal mean value and absent systolic wall thickening or wall thinning. Mean MIBI-uptake of viable (n = 676; 79 +/- 14%) and scar segments by MRI (n = 124; 31 +/- 16%) was significantly different (P < 0.001). Segmental MIBI-uptake vs end-diastolic wall thickness (r = 0.7) and systolic wall thickening (r = 0.71) yielded a fair correlation. The highest values as regards sensitivity and specificity of MIBI-uptake in predicting the presence of scar were 89% and 96% respectively for MIBI-uptake < or = 50%. However, of the 136 segments with MIBI-uptake < or = 50%, 26 (19%) were viable by MRI, resulting in a positive predictive accuracy for scar tissue of 81%. Of the 26 segments diagnosed as scarred by MIBI-SPECT but viable by MRI, 25 (96%) were located in the inferoseptal region. MIBI-SPECT seems useful in the detection of viable myocardium after anterior myocardial infarcts, but over-estimates scar in the inferoseptal regions. Perfusion defects in these regions could be confirmed or denied by additional evaluation of myocardial morphology and function by MRI or tissue metabolism by positron emission tomography (PET).
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PMID:Regional 99mTc-methoxyisobutyl-isonitrile-uptake at rest in patients with myocardial infarcts: comparison with morphological and functional parameters obtained from gradient-echo magnetic resonance imaging. 817 90

201Tl myocardial SPECT is known for better sensitivity, specificity, and accuracy than planar images in detecting coronary artery disease and diagnosing myocardial viability. SPECT images are also superior to planar images in diagnostic sensitivity and anatomical orientation. However, as limitation of the spatial resolution of the machine, we often encounter poor SPECT plower image quality in patients with decreased wall thickness. To test the accuracy of SPECT images in patients with marked thinning of the left ventricular wall, as occurs in dilated cardiomyopathy, we performed a experimental study using myocardial phantom with 7 mm wall thickness. Tomographic image of the phantom images were rather heterogeneous, though no artificial defect was located. Dilated cardiomyopathy is thought to be characterized by patchy defects in the left ventricle. Careful attention should be given to elucidating myocardial perfusion in patients with a thin left ventricle wall, as there are technical limitations in addition to clinical features.
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PMID:[Effect of wall thickness of left ventricle on 201Tl myocardial SPECT images: myocardial phantom study]. 880 47


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