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1.
The electrocardiogram (ECG) is widely used for detection of left ventricular hypertrophy (LVH). However, whether changes in ECG LVH during antihypertensive therapy predict changes in LV mass remains unclear. Baseline and year-1 ECGs and echocardiograms were assessed in 584 hypertensive patients with ECG LVH by Sokolow-Lyon or Cornell voltage-duration product criteria at entry into the Losartan Intervention For Endpoint reduction in hypertension (LIFE) echocardiographic substudy. A >/=25% decrease in Cornell product defined regression of ECG LVH; a <25% decrease defined no significant regression; and an increase defined progression of ECG LVH. Regression of echocardiographic LVH was defined by a >/=20% reduction in LV mass. After 1 year of therapy, 155 patients (27%) had regression of ECG LVH, 286 (49%) had no significant change, and 143 (25%) had progression of ECG LVH. Compared with patients with progression of ECG LVH, patients with no significant decrease and patients with regression of ECG LVH had stepwise greater absolute decreases in LV mass (-16+/-33 vs -29+/-37 vs -32+/-41 g, P<0.001), greater percent reductions in LV mass (-5.7+/-14.6 vs -11.3+/-13.6 vs -12.3+/-15.6%, P<0.001), and were more likely to decrease LV mass by >/=20% (11.2 vs 24.8 vs 36.1%, P<0.001), even after adjusting for possible effects of baseline and change in systolic and diastolic pressures. Compared with progression of ECG LVH, regression of the Cornell product ECG LVH is associated with greater reduction in LV mass and a greater likelihood of regression of anatomic LVH.  相似文献   

2.
To define the availability of Doppler echocardiography in evaluating left ventricular hemodynamic changes induced by some clinical findings of acute coronary insufficiency, we selected 12 patients with angina and 32 affected by acute myocardial infarction. Doppler echocardiography was performed at hospital admittance and during recovery time. Left ventricular contractility was defined on the systolic aortic flow spectrum by measuring the aortic velocity maximum, the time to peak/left ventricular ejection time ratio, and the cardiac output. During the first examination, left ventricular contractility significantly decreased in patients with angina and in those with acute myocardial infarction. After the acute phase, these parameters slightly improved. Left ventricular diastolic filling was evaluated in the transmitral flow. A decreased E-wave velocity and an increased late component (A wave) with inversion of the E/A wave ratio were found in patients with acute myocardial infarction during the first examination. This morphology inverts when the patients stabilize. On the contrary, this ratio stayed above one during and after angina. In this study, we also defined the usefulness of the color Doppler method in setting up criteria to identify some early morphological complications of acute myocardial infarction in 12 patients with acute infarction and a new systolic murmur. This technique showed an ischemic rupture of the ventricular septum in five cases and mitral regurgitation in seven. The color Doppler method has allowed us to obtain a semi-quantitative assessment of the mitral regurgitation and the location of the ventricular septal defect.  相似文献   

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Although echocardiography is ideally suited for repetitive use on a patient for evaluation of left ventricular function, the value of this application is minimised by the uncertainty as to whether changes in left ventricular dimensions observed on a patient at different times or by different observers are real or result from the ultrasonic beam penetrating the left ventricle at different angles. Accordingly, an instrument was designed and constructed in our laboratory to improve the reproducibility of echocardiographic measurements of left ventricular dimensions. The instrument represents an orthogonal reference frame by means of which the spatial orientation of the ultrasonic beam relative to the chest is determined and reproduced in subsequent studies, while the point of entrance of the beam is marked on the chest wall. Using this instrument, left ventricular echograms were initially recorded on a group (I) of 23 subjects with or without heart disease and the study was repeated 8 hours to 49 (mean 7) days later by the same observer and also, in 16 cases, by an independent observer. The average values from 2 to 6 (mean 4) heart cycles were used for the left ventricular end-diastolic dimension (Dd), end-systolic (Ds) dimension, and their difference (delta D). Differences in all three variables between studies were random and statistically insignificant, never exceeding 3-5 mm for Dd or Ds, and 4 mm for deltaD. For comparison, left ventricular internal dimensions were also obtained in a seprate group (II) of 14 subjects by the standard method of using the mitral valve as an internal landmark, without the benefit of this instrument. All 14 subjects had the initial study repeated within 8 hours to 11 (mean 3-8) days later by the same and also by an independent observer. Though in the group as a whole there was no significant difference in left ventricular dimensions between studies, individual variations reached 11 mm for Dd, 9 mm for Ds, and 9 mm for deltaD, and the degree of scatter was significantly larger than in group I. This initial experience indicates that the use of this instrument improves the reproducibility and enhances the reliability of estimates of echocardiographic left ventricular dimensions and function on a patient examined at different times by the same or independent observers.  相似文献   

5.
Twelve patients with aortic stenosis (gradient 62 (25) mm Hg), and six normal subjects were examined using M mode echocardiography before and during submaximal bicycle exercise. Normal subjects showed a progressive fall in the end systolic minor axis dimension of the left ventricle and a rise in end diastolic dimension, giving an increase in stroke dimension and shortening fraction of 45% and 37% respectively at peak exercise. Patients with aortic stenosis showed no consistent alteration in either end systolic or end diastolic dimension, and consequently stroke dimension was unchanged during exercise. None of the patients with an abnormal exercise response had evidence of left ventricular failure at rest, and all but one completed the exercise protocol without undue dyspnoea. Non-invasive exercise testing in patients with aortic stenosis may detect abnormalities of left heart function which are not apparent at rest. These abnormalities may provide early evidence either of severe aortic stenosis or of incipient left ventricular failure.  相似文献   

6.
The present study was designed to determine whether the long axis of the left ventricle is elongated in patients with aortic regurgitation. Among 445 patients with valvular disease who were followed in our hospital from April 1986 to February 1987, 14 with aortic regurgitation [AR: age: 46.1 (mean) +/- 17.6 (standard deviation) years] and 17 with mitral regurgitation (MR: age: 48.8 +/- 18.0 years) were selected for analysis. They all had optimal quality images in the apical view of the two-dimensional echocardiograms adequate for the evaluation and moderate to severe regurgitation at the time of Doppler examination. The control group consisted of 15 subjects without evidence of organic heart disease (age: 44.9 +/- 17.7 years). There was no difference in the mean duration of the clinical course between AR (14.9 years) and MR (13.4 years). The following measurements were made in the apical right anterior oblique view: Lo (long-axis distance of the outflow tract); from the left ventricular apex to the center of the aortic annulus, L (long-axis distance of the left ventricle); from the apex to the junctional point between the aortic and mitral valves, Li (long-axis distance of the inflow tract); from the apex to the center of the mitral valve ring, and d1, d2 and d3 (apical, middle and basal short axes of the left ventricle); the distances perpendicular to the each long axis at the levels of 1/4, 2/4 and 3/4 of the long axis. All data were corrected by means of the calibration scale, and compared as indices divided by the body surface area.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Left ventricular (LV) function in 45 patients with native aortic valve infective endocarditis was studied in order to identify high surgical risk patients and the pattern of irreversible myocardial damage. LV function was studied by M-mode and 2D-echocardiography (LV volumes; ejection fraction, EF; peak systolic pressure to end-systolic volume ratio (PAP/ESV) as an index of myocardial contractility; LV mean systolic wall stress as an index of LV afterload and the radius to thickness ratio (R/Th). Thirteen patients underwent aortic valve replacement with an overall operative mortality of 15%. The cause of death was intractable heart failure. Different EF vs stress relationships could be described for different level of myocardial contractility: patients with intractable heart failure had a severely depressed myocardial contractility so that for a given level of LV stress, EF was significantly lower. High operative risk patients were identified by the PAP/ESV vs R/Th relation. All surgical deaths occurred in patients with a severely depressed myocardial contractility (PAP/ESV less than 2) and inadequate hypertrophy (R/Th greater than 4). Reversal of LV dysfunction in patients with moderately depressed myocardial contractility depended on the pattern of LV hypertrophy; a normal post-operative EF was achieved only in patients with adequate hypertrophy (R/Th less than 4).  相似文献   

8.
Left ventricular adaptation to obstruction to ejection (aortic stenosis and coarctation) was studied by echocardiography in 85 patients from 1 month to 20 years of age. Group I: 40 children with pure congenital aortic stenosis. Group II: 45 children with coarctation at the aortic isthmus without associated shunts. All patients also underwent cardiac catheterisation. The results were compared with a control series of 35 normal subjects. Echocardiographic recordings of adequate quality for studying the left ventricle and parameters of myocardial performance were obtained in all patients. In Group I estimations of the left ventricular systolic pressure and the ventriculo-aortic pressure gradient were made and compared to the results of catheterisation. Symmetric left ventricular hypertrophy was recorded in both groups (h/R, p less than 0,001; myocardial mass, p less than 0,001) but this was more common in aortic stenosis (92%) than in coarctation (53%). Left ventricular function was similar in both groups with an increased fractional shortening (p less than 0,001) and velocity of circumferential fibre shortening (p less than 0,001). Good correlations were obtained between echocardiographic and hemodynamic measurements of left ventricular pressures and ventriculo-aortic pressure gradients (pressure R = 0,83, gradient R = 0,73) using the formula for systolic left ventricular pressure = SLV = 225 X PPs/Ds. This proved very useful in assessing which children needed surgery.  相似文献   

9.
A case of spontaneous echocardiographic contrast in the left ventricle of a patient with severe aortic insufficiency is presented. This contrast appeared through the mitral valve which opened mainly during tele-diastole. Pulsed Doppler showed the blood flow responsible was laminar and of normal velocity. The mechanism of spontaneous intraventricular contrast cannot be attributed to poor left ventricle function or to high-velocity turbulent flow. We believe that spontaneous contrast was triggered by the decrease in proto-diastolic mitral flow secondary to aortic insufficiency. Transient stagnation of blood in the left atrium might modify the echogenic characteristics of the blood which persist during the passage of the flow through the left ventricle.  相似文献   

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An echocardiogram from the left ventricle may be used to estimate left ventricular volume and rate of circumferential fiber shortening, to measure posterior wall and interventricular septal thickness and to evaluate the normality of septal motion. Extended application of this technique in this laboratory has emphasized the need for a more standardized means of transducer location and direction. The effect of placing the ultrasonic transducer in several intercostal spaces along the left sternal border was tested in 14 patients. Variability in the left ventricular dimension and the difference in this dimension from end-diastole to end-systole were greater than for duplicate measurements from the same interspace. A system has been developed for more consistent placement of the transducer in each patient, using intracardiac landmarks and observation of transducer orientation to record specific cardiac structures.  相似文献   

13.
Aortic root motion was studied in 24 normal volunteers at rest and during the Valsalva maneuver, isometric exercise, and amyl nitrite inhalation. In addition root motion was correlated with the stroke volumes determined at cardiac catheterization in 24 patients. The root has distinct systolic movement, the amplitude and duration of which were easily measured both at rest and during the interventions. At rest,the mean (+/-1 SE) systolic amplitude of the anterior aortic wall was 11.2 +/- 0.5 mm and that of the posterior wall 9.5 +/- 0.3 mm. During the strain phase of the Valsalva maneuver anterior wall amplitude fell to 8.2 +/- 0.4 mm and the posterior wall to 7.3 +/- 0.5 mm (P less than 0.001). With release, anterior wall amplitude rebounded to 12.5 +/- 0.8 mm and the posterior wall to 10.8 +/- o.5 mm, values greater than control (P less than 0.01). With isometric exercise there was no change in amplitude compared to rest; however, amyl nitrite caused an increase in the anterior wall to 13.5 +/-0.8 mm and posterior wall to 11.9 +/-0.6 mm (P less than 0.01). In the patient group the amplitude of posterior wall motion correlated weakly with cardiac index (r = 0.63) and stronger with stroke index (r = 0.78). This study quantifies the echocardiographic pattern of normal aortic root motion. The findings indicate that the aortic root motion is an index of stroke volume; they further suggest that root motion is acutely sensitive to variations in stroke volume since its amplitude changed in accord with the documented effects of the employed maneuvers on stroke volume.  相似文献   

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Left ventricular systolic and diastolic performance was examined using Doppler and M-mode echocardiography in 42 patients with chronic renal failure before and after hemodialysis. Twenty patients with left ventricular hypertrophy, 22 without hypertrophy and 30 normal subjects were studied. Chronic renal failure patients showed significantly larger chamber diameters of the left ventricle, left atrium and right ventricle than did normal subjects. This group also exhibited greater fractional shortening, stroke volume and cardiac output. Before hemodialysis, patients with left ventricular hypertrophy had a significantly higher cardiac output and the greater ratio of late to early diastolic peak flow velocities (A/R) than did patients without hypertrophy. After hemodialysis, there were significant reductions in blood pressure, ventricular and atrial dimensions, stroke volume and cardiac output. The velocities of early and late diastolic left ventricular filling and the deceleration rate were also significantly reduced. The heart rate, A/R, deceleration half time, and the ratio of deceleration half time to acceleration half time (DHT/AHT) were significantly increased. The greater the amount of fluid removed, the greater the changes in the above values. Patients with left ventricular hypertrophy exhibited significant reductions in fractional shortening, ejection fraction, stroke volume and cardiac output, compared to those without hypertrophy. However, patients without hypertrophy showed more significant decrease in the acceleration half time and increase in DHT/AHT than did patients with hypertrophy. These findings demonstrated normal systolic function and impaired diastolic properties in patients with chronic renal failure, who had left ventricular hypertrophy unaccompanied by dilatation.  相似文献   

16.
A study of the left ventricular function based on the haemodynamic data combined with those provided by biplane cineangiography was performed in 35 cases with left ventricular volume overload (20 cases of mitral incompetence and 15 of aortic insufficiency). The importance of the haemodynamic changes and of the adaptation mechanisms set up were described. The more intense dilatation-hypertrophy of aortic incompetence than of mitral incompetence plays an essential part. The role of Starling's mechanism is underlined. Estimation of the contractile value of the myocardium, taken into account the mechanical overload and the conditions of late-diastolic lengthening of the fibre and of impedance to left ventricular ejection was determined. An obvious myocardial failure, demonstrated in approximately one third of the cases, by determination of some contractility indices estimated in the ejection phase, Vf sigma max in particular, the only one valid in the presence of valvular regurgitation. In the other cases, the moderate decrease of myocardial contractility was masked by compensatory mechanisms.  相似文献   

17.
Previous retrospective echocardiographic studies have reported a higher embolic potential of left ventricular thrombi with protruding configuration and patterns of mobility. The present study was performed to prospectively assess the shape and mobility patterns of left ventricular thrombi and their spontaneous changes with time. Two-dimensional echocardiograms were obtained in 109 consecutive patients with acute anterior myocardial infarction within 24 hr of the onset of symptoms, every 24 hr until day 5, every 48 hr until day 15, and then every month for a follow-up of 1 to 29 (mean 14 +/- 8) months in the survivors. None of the patients were treated with anticoagulants or platelet inhibitors during the study period. Left ventricular thrombi, detected in 59 patients (54%), appeared from 1 to 362 (mean 12 +/- 47) days after myocardial infarction. At first detection, the shape was mural in 21 patients and protruding in 38; patterns of mobility were present in eight patients. During follow-up, changes in the shape of the thrombi were noted in 24 patients (41%; from mural to protruding in nine, from protruding to mural in 15). These variations were encountered between 2 and 490 (mean 64 +/- 117) days after the first observation of the thrombus. Patterns of mobility, previously detected in eight patients, disappeared in five of eight within 2 to 28 (mean 14 +/- 11) days.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

18.
It is important to know the natural evolution of the changes in left ventricular dimensions and contractility in AR if one wishes to determine the critical echocardiographic values at which LV function starts to deteriorate. This was the aim of our echocardiographic study of 90 patients with chronic pure AR in whom we analysed the changes in LV dimensions, mass and contractility for 11 to 84 months (average 34.6 months). The patients were divided into 2 groups according to the degree of ventricular dilatation (delta DD): Group A: delta DD less than 30% (58 patients), Group B: delta DD greater than 30% (32 patients). The annual mean increase in diastolic and systolic LV dimensions and myocardial mass in each group was: 1.5 mm vs 3.2 mm (p less than 0.02); 0.9 mm vs 4.1 mm (p less than 0.003), 14 g vs 24 g (p = 0.07 NS) respectively. The parameters of the systolic function were normal in Group A (EF = 68 +/- 8% and % FS = 38 +/- 6%) and decreased in Group B (EF = 58 +/- 13%, % FS = 32 +/- 9%). A significant annual decrease of the mean values of these parameters was only observed in patients of Group B (EF = 1.8% per year; % FS = -1.2% per year). These results are on average of unequal individual variations: variations of DD or EF greater than the variability due to the reproducibility of the method were only observed in 43 patients. The number of patients in whom echocardiographic changes were observed was comparable in Groups A and B.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
To study diastolic function we digitized M-mode echocardiograms in 18 acromegalic patients (A) and compared them to an age matched control population (C). Wall thickness and left ventricular (LV) mass index are frankly increased in A (p less than 0.001). Filling pattern of the LV shows in A a prolongation of the isovolumic relaxation period (IRP) (p less than 0.001), an increase of the percentage dimension change of LV during IRP (p less than 0.001) and a reduction of the percentage dimension change during the rapid filling period (p less than 0.01). Our results indicate that relaxation is abnormal in A; this abnormality should be interpreted as a mere consequence of LV hypertrophy.  相似文献   

20.
Whether mitral insufficiency is a marker of decreased left ventricular function in patients undergoing aortic valve replacement for sever aortic stenosis was examined. Hemodynamic measurements in 26 patients with pure aortic stenosis (Group 1), 17 patients with aortic stenosis and grade 1 or 2 mitral insufficiency (Group 2) and 19 control patients were compared. All patients were free of significant coronary artery disease. Ventriculograms were digitized for calculation of ejection fraction, ventricular volumes and wall stress. Despite similar aortic valve areas, Group 2 patients had more advanced symptoms. Cardiac index was comparably decreased in Group 1 (2.6 +/- 0.4 liters/min per m2) and Group 2 (2.7 +/- 0.8 liters/min per m2) compared with the control group (3.8 +/- 0.6 liters/min per m2). Left ventricular end-diastolic and end-systolic volume indexes were increased only in Group 2 (119 +/- 35 and 73 +/- 36 ml/m2, respectively). Likewise, end-systolic wall stress was increased only in Group 2 (149 +/- 54 kdynes/cm2). Ejection fraction was decreased to a greater extent in Group 2 (42 +/- 17%) than in Group 1 (59 +/- 13%) as compared with values in the control group (68 +/- 5%). Although an inverse relation existed between ejection fraction and end-systolic stress in all groups, the ejection fraction (extrapolated to end-systolic stress = 0) was decreased in Group 2, and the slope of the relation was increased in Groups 1 and 2. The end-systolic stress/end-systolic volume index ratio, an index of ventricular performance, was also decreased to a greater extent in Group 2.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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