Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to study left ventricular function in idiopathic hypertrophic subaortic stenosis (IHSS), left ventricular echograms were analyzed by computer and compared with results in normal subjects. Systolic function was consistently normal or above normal even in the presence of severe diastolic abnormalities. Wide variation in diastolic function in IHSS allowed separation of patients into three groups on the basis of the left ventricular peak filling rate. Because of the severe septal hypertrophy and hypokinesia, peak left ventricular filling rate is predominantly determined by the rate of free wall thinning. Patients in group 1 had rapid left ventricular filling rates, those in group 2 had normal filling rates, and those in group 3 had slow filling rates. With reduction in left ventricular peak filling rate caused by impaired free wall thinning, there was progressive increase in 1) duration of the rapid filling phase, 2) delay of mitral valve opening, 3) asynchrony between septum and posterior wall, 4) incidence of angina, and 5) incidence of atrial fibrillation.
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PMID:Echocardiographic assessment of left ventricular filling and septal and posterior wall dynamics in idiopathic hypertrophic subaortic stenosis. 56 45

In clinical and experimental studies we assessed images of digital subtraction coronary angiography (DSA) for evaluating regional myocardial perfusion. Myocardial perfusion was assessed by injecting contrast medium into the coronary artery, and by imaging the regional myocardium using DSA. On the time-density curve obtained from the myocardial region of interest, we calculated the time to peak concentration (TPC) and the exponential washout rate (T). TPC and T were measured in five patients with stable effort angina pectoris (AP) and left anterior descending (LAD) lesions before and after percutaneous transluminal coronary angioplasty (PTCA). The values of 1/T increased significantly from 0.09 +/- 0.02 l/sec to 0.21 +/- 0.04 l/sec (p less than 0.01) after PTCA, but l/TPC did not change. No significant difference in ejection fractions was observed between the patients with AP and the normal subjects (n = 7), while the regional percent area shrinkage in the anterolateral and apical regions supplied by the LAD was significantly decreased in the patients with AP compared with those of normal subjects (anterolateral: 39.8 +/- 8.8% vs 51.3 +/- 6.8%, apical: 36.6 +/- 8.4% vs 52.4 +/- 13.4%, both p less than 0.01). In 10 anesthetized dogs with varying degrees of reduction in the left circumflex coronary artery (LCX) blood flow (CBF: categories of stenosis (S1-S5), we compared 1/TPC and 1/T with regional myocardial function (systolic wall thickening: %WTh). With varying LCX stenosis, there were no significant changes in heart rate and mean aortic pressure and significant linear correlations were observed between %WTh and 1/TPC (r = 0.51), between %WTh and 1/T (r = 0.55). At S1 (CBF: 100-90% of the control), neither %WTh nor 1/TPC differed from that of the controls, but 1/T was significantly decreased (80% of the controls, p less than 0.01). From S3 (CBF: 79-60%) to S5 (CBF: 39-0%), %WTh, 1/TPC and 1/T were significantly decreased from those of the control levels (all p less than 0.01). However, at S5 (CBF: 39-0%) the values of 1/TPC (71% of controls) and 1/T (33%) did not differ from those at S4; whereas, %WTh was markedly reduced and the systolic thinning of the ventricular wall occurred at S5. Therefore, in critical coronary stenosis, 1/T was more sensitive than 1/TPC or wall dynamics for assessing myocardial ischemia. Both 1/TPC and 1/T, as well as %WTh, were useful for assessing moderate myocardial ischemia; however, these DSA indices had considerable limitations for evaluating the severity of myocardial ischemia when CBF was markedly reduced.
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PMID:[Comparison of myocardial perfusion assessments by digital subtraction angiography with those of left ventricular wall dynamics]. 213 31

Diffuse narrowing of the internal mammary artery graft (IMAG), the thinning phenomenon, was found in 8 (6.7%) out of 120 IMAGs underwent postoperative angiography. There were 6 males and 2 females, and mean age was 55.3 ranged from 37 to 70 year-old. There was no significant correlation with hyperlipidemia, diabetes mellitus or hypertension. Grafted coronary arteries were 6 anterior descending, one diagonal and one circumflex arteries. Diameter of them was 1.5 mm in one and 2 mm in 7. severity of stenosis of proximal coronary artery was 100% in one, 90-99% in one and less than 90% in 6. Undivided sizable costal or pericardial branches were found in 4 patients. All eight patients were alive without angina, although mild positive stress EKG changes were noted in two patients. In conclusion, a high resistance state such as a good competitive native coronary flow was thought to be the most important factor for the diffuse narrowing of IMAG, and close follow up should be needed because its outcome is still unknown.
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PMID:[Diffuse narrowing of the internal mammary artery graft--the thinning phenomenon]. 257 38

To assess the usefulness of X-ray computed tomography (CT) and magnetic resonance imaging (MRI) in detecting and evaluating ischemic heart disease, conventional and enhanced CT were performed for 180 patients (150 with transmural infarction, 12 with subendocardial infarction, and 18 with angina pectoris). MRI examinations were performed for 38 patients (31 with transmural infarction, three with subendocardial infarction, and four with angina pectoris). With enhanced CT, two findings in the myocardium were direct evidence of myocardial infarction: 1. filling defects on the early scans, and 2. late enhancement of the myocardium on the delayed scans. The former were observed mainly at the sites of recent anterior myocardial infarction and the latter were seen in about half of the patients with recent and remote anterior myocardial infarctions. However, these findings were inadequately imaged in patients with inferoposterior infarction and subendocardial infarction. Among 137 patients with transmural infarction, enhanced CT revealed left ventricular aneurysms in 51 (37%) and ventricular thrombi in 26 (19%). ECG-gated MRI apparatus having a superconducting magnetic operating at 0.25 Tesla was used, and data for this study were collected using the single-slice spin echo technique. In eight of nine patients with acute myocardial infarction, gated MRI demonstrated the infarcted myocardium as regions of high signal intensity relative to that of the adjacent normal myocardium. Such a difference in MRI signal intensity was scarcely recognized in the chronic stage of myocardial infarction, but the indirect findings of infarction, such as regional wall thinning, wall motion disturbances, left ventricular aneurysms, and ventricular thrombi were easily detected using MRI. No characteristic finding was obtained by CT or MRI in patients with angina pectoris.
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PMID:[Diagnostic evaluation of ischemic heart disease by X-ray computed tomography and magnetic resonance imaging]. 342 26

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

To detect abnormal interventricular septal (IVS) motion during exercise-induced ischemia, ergometer exercise echocardiography was performed using a specially devised transducer in 12 patients (pts) with effort angina (left anterior descending artery disease) and 10 normal subjects (N) at rest, and during exercise and recovery. During exercise, percent systolic IVS thickening (% delta T) and IVS excursion (Ex) increased from 52 +/- 13% at rest to 73 +/- 19% and from 7.0 /- 1.3 mm at rest to 10.6 +/- 1.9 mm, respectively, in N, and also from 52 +/- 23% to 67 +/- 36% and from 7.3 +/- 1.9 mm to 9.7 +/- 2.1 mm in all of 3 pts with distal left anterior descending artery disease. On the other hand, in 9 pts with proximal left anterior descending artery disease, % delta T and Ex during exercise decreased from 41 +/- 17+ at rest to 26 +/- 25% and from 7.7 +/- 1.2 mm to 5.1 +/- 4.6 mm. The late systolic wall thickening of IVS was observed during peak exercise in 2 of the 9 pts, one of whom exhibited systolic IVS thinning and a decrease in diastolic thickness (from 6 mm to 4.5 mm). In 5 pts with IVS asynergy during exercise diastolic IVS thickness increased maximally from 10.2 +/- 3.3 mm at rest to 11.4 +/- 3.5 mm during recovery (reactive hyperemia). Exercise echocardiography is useful to predict the location of left anterior descending artery disease and to evaluate IVS performance during exercise-induced ischemia.
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PMID:[Exercise echocardiography: interventricular septal thickness and motion in patients with effort angina during ergometer exercise (author's transl)]. 726 97

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

Dynamic changes in left ventricular wall thickness represent a function of the myocardium which can be described, in normal subjects or in disease, without reference to behavior of other parts of the wall. Abnormalities of amplitude, rate and timing of wall thickness change interact in influencing overall ventricular performance, so that even this local function cannot be expressed as a single "index". Infarcted and acutely ischemic myocardium display reduced amplitude of thickness change. The degree to which they also show delayed wall dynamics in man is uncertain. Cross-sectional echocardiography has not been used to examine this aspect of regional thickness change, mainly because of the difficulties of processing "real-time" images. In the stable state of ischemic heart disease, such as exists in patients with angina, abnormalities of timing are common, even in the absence of significant reduction in overall thickness change, and lead to impaired energy transfer from the myocardium to the circulation. The degree of organization involved in normal myocardial function is better appreciated when one considers the complex phenomena which result from its disruption. In particular, rapid wall thinning in early diastole, normally associated with rapid filling, is revealed as an inherent property of the wall when it becomes dissociated from filling because relaxation is incoordinate. This demonstration of the active processes involved in ventricular relaxation provides an example of how the study of ischemic heart disease, in its differing local effects, may provide insight into the normal physiology of the myocardium.
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PMID:Wall thickness changes considered as regional myocardial function in ischemic heart disease. 745 Jun 62

Coronary artery diseases may categorized into asymptomatic disease, angina pectoris, myocardial infarction, chronic heart failure, and sudden coronary death. Unstable angina, acute myocardial infarction, and sudden cardiac death are known as the acute coronary syndromes. Coronary atheroma is unstable in the patients with acute coronary syndromes. Stable plaques will be unstable when dynamic alterations occur. The alterations are plaque rupture, plaque hemorrhage, coronary thrombosis and vasospasm. They act each other. We analysed the histopathology of coronary arteries who died of acute myocardial infarction in 85 cases. It showed that the risk factors of plaque rupture are clusters of form cells, eccentric plaque with soft lipid rich core, and thinning of fibrous cap in atheroma. Most of these cases ruptured at edge of the atheroma.
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PMID:[Pathogenesis of acute coronary syndromes]. 978 Jul 33


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