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Cardiac disease in diabetes mellitus and in the metabolic syndrome consists of both vascular and myocardial abnormalities. The latter are characterised predominantly by diastolic dysfunction, which has been difficult to evaluate in spite of its prevalence. While traditional Doppler echocardiographic parameters enable only semiquantitative assessment of diastolic function and cannot reliably distinguish perturbations in loading conditions from altered diastolic functions, new technologies enable detailed quantification of global and regional diastolic function. The most readily available technique for the quantification of subclinical diastolic dysfunction is tissue Doppler imaging, which has been integrated into routine contemporary clinical practice, whereas cine magnetic resonance imaging (CMR) remains a promising complementary research tool for investigating the molecular mechanisms of the disease. Diastolic function is reported to vary linearly with age in normal persons, decreasing by 0.16 cm/s each year. Diastolic function in diabetes and the metabolic syndrome is determined by cardiovascular risk factors that alter myocardial stiffness and myocardial energy availability/bioenergetics. The latter is corroborated by the improvement in diastolic function with improvement in metabolic control of diabetes by specific medical therapy or lifestyle modification. Accordingly, diastolic dysfunction reflects the structural and metabolic milieu in the myocardium, and may allow targeted therapeutic interventions to modulate cardiac metabolism to prevent heart failure in insulin resistance and diabetes. [ABSTRACT FROM AUTHOR]

Aims: To examine differences in measurements of left ventricular dimensions and function, and prognostic value between local investigators and a core laboratory in a multicentre serial echocardiographic study.Methods and Results: Seven hundred and fifty-six patients with acute myocardial infarction and preserved left ventricular function were examined at baseline and after 3 months with measurements by the biplane Simpson’s method, and followed prospectively from 3 to 24 months. At baseline and 3 months local investigators relative to the core laboratory measured lesser end-diastolic volume by 8 and 6 ml (P<0·001), end-systolic volume by 3 and 2 ml (P<0·01), and ejection fraction by 0·0 and 0·6% (P<0·01), respectively. Local investigators and the core laboratory measured an increase in left ventricular end-diastolic volume of 8·6 and 6·9 ml, and in left ventricular end-systolic volume of 5·2 and 4·3 ml, and a decrease in left ventricular ejection fraction of 0·6 and 0·0%. Using the Cox proportionate hazards model, the prognostic value for subsequent clinical endpoints was significant both for the 3-month values (P<0·05) and changes (P<0·005) measured by the core laboratory, but not by local investigators.Conclusion: Only measurements in the core laboratory had significant prognostic value for subsequent clinical endpoints. These results strongly support the use of a core laboratory in studies employing echocardiographic measurements. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved. [ABSTRACT FROM AUTHOR]

Aims: Two-dimensional (2D) echocardiography has been widely applied to measure left ventricular volumes with the biplane Simpson's method in the assessment of left ventricular remodelling following an acute myocardial infarction. This volume formula is based upon tracings of endocardium and measurement of long axis on left ventricular images. In the present follow-up study of post-myocardial infarction patients we evaluated the prognostic impact of changes in left ventricular areas and geometry versus long axis to determine if only long-axis measurements may be used for prognostic purposes.Methods and Results: Two-dimensional echocardiographic video recordings of the apical four-chamber and long-axis views were obtained in 756 patients 2–7 days and 3 months following an acute myocardial infarction. All videotapes were sent to a core laboratory and left ventricular volumes were measured with the biplane Simpson's method in end-diastole and end-systole. During the first 3 months 44 patients had suffered one of the following end-points and were excluded: cardiac death, recurrent myocardial infarction, heart failure or chronic arrhythmia. Over a period of 3–24 months 58 such end-points occurred. With the Cox proportional hazards model the increase in left ventricular systolic volume was the strongest predictor for such events (Chi-square 18·5, P<0·0001), followed by an increase in end-systolic area (Chi-square 17·0, P<0·0001) and end-systolic spherity index (Chi-square 8·74,P =0·003). The increase in end-systolic long axis had only a borderline predictive value (Chi-square 4·3, P=0·04). The change in long-axis shortening from end-diastole to end-systole had no significant predictive value at all.Conclusion: In the studied population changes in left ventricular area and geometry, but not in the long axis, were mainly related to cardiac morbidity. The proper assessment of changes in left ventricular dimensions should therefore be based upon tracings of the area and not on long axis measurements only. [ABSTRACT FROM AUTHOR]

Objective: Left ventricular (LV) remodelling following acute myocardial infarction has generally been studied in patients with LV ejection fraction (EF) < 40%, and it has been shown that this process can be attenuated by ACE inhibitors. Little is known regarding LV remodelling in patients with LVEF > or = 40% or the effects of treatment in this patient cohort. The DEFIANT II study (Doppler Flow and Echocardiography in Functional cardiac insufficiency) included 542 post-infarction patients with LVEF 25-50% without overt heart failure within 13 days following acute myocardial infarction (AMI). They were then randomized to nisoldipine coat-core (CC) or placebo and followed up for 6 months.Design: Two-dimensional echoes were obtained after 8 (5-13) days and 6 months following AMI.Setting: LV end diastolic (ED) and end systolic (ES) volumes (V) were calculated in 503 patients with technically satisfactory paired echoes using the biplabe method of discs in a core laboratory.Subjects: Group A. 217 patients with baseline EF 40-50%, of whom 112 were randomized to nisoldipine and 104 to placebo (one patient was taken off study medication). Group B. 286 patients with EF 25-39%, of whom 145 were randomized to nisoldipine and 141 to placebo.Results: LVEDV was 175 (+/-45) ml in Group A vs 203 (+/-49) ml in Group B (p = 0.001) at baseline and 184 (+/-48) ml vs 213 (+/-56) ml (p = 0.001), respectively, at 6 months. LVESV at baseline was 97 (+/-42) ml in Group A vs 133 (+/-37) ml in Group B (p = 0.001), and 106 (+/-34) ml vs 134 (+/-45) ml (p = 0.001) at 6 months, respectively. The increase of LVESV was 9 (+/-29) ml in Group A vs 2 (+/-35) ml in Group B (p = 0.007). LVEF decreased by 2 (+/-6)% in Group A vs an increase of 3 (+/-6)% in Group B (p = 0.001). Treatment with nisoldipine had no influence on LV volumes in either of the two groups or in the total study group.Conclusion: LV dilatation 6 months following AMI in patients with EF 40-50% was similar in end diastole, but more pronounced in end systole vs patients with EF 25-39%. LV remodelling did not change significantly after nisoldipine treatment. [ABSTRACT FROM AUTHOR]

This article focuses on a study that was designed to determine whether aortic regurgitation (AR) and mitral valve prolapse (MVP) are specifically associated with Down's syndrome, or occur in a comparably retarded population without Down's syndrome. The 92 control subjects had mental retardation attributable to low birth weight or perinatal asphyxia. In this case-control study, AR and MVP occurred about three times more often in institutionalized adults with Down's syndrome compared with those whose mental retardation was due to perinatal asphyxia or low birth weight. The low frequency of AR in both groups probably explains why the difference between the two groups did not achieve statistical significance.

Regional and global left ventricular function was assessed in 23 neonates with persistent pulmonary hypertension using computer assisted analysis of their left ventricular echocardiograms and compared with that in 50 healthy neonates. End diastolic left ventricular dimension was normal and end systolic dimension increased while percentage left ventricular shortening and peak velocity of circumferential fibre shortening decreased indicating impaired systolic performance. The peak rate of increase in left ventricular diameter in early diastole was significantly decreased and the durations of the rapid filling and isovolumic relaxation periods were prolonged suggesting resistance to left ventricular filling due to changes in diastolic myocardial properties. This abnormal left ventricular cavity function may have been due to a combination of increased diastolic wall thickness, reduced percentage systolic wall thickening, increased relative wall thickness, and pronounced reduction in peak rates of systolic wall thickening and diastolic wall thinning Seven neonates with persistent pulmonary hypertension died, and of the three examined at necropsy all had left ventricular hypertrophy and two extensive subendocardial haemorrhage and infarction affecting the right and left ventricular papillary muscles. Thus left ventricular dysfunction appears to be a common feature in neonates with this disorder and may be readily detected using computer analysis of left ventricular echocardiograms. Unfortunately, no single echo measurement was useful prognostically. Left ventricular dysfunction in persistent pulmonary hypertension probably results from a combination of hypoxaemia, acidaemia, and pulmonary hypertension, and although it may contribute to the high mortality in this syndrome, a correlation between the severity of left ventricular dysfunction and clinical outcome could not be shown. [ABSTRACT FROM PUBLISHER]

We assessed the effects of age related changes in chamber size, wall thickness, and heart rate of left ventricular function in 78 normal children, aged 1 1/2 to 12 1/2 years, using computer analysis of their left ventricular echocardiograms. Left ventricular cavity size and wall thickness increased linearly with age. Left ventricular fractional shortening, percentage of wall thickening, and the ratio of end-diastolic wall thickness to cavity radius (H/R ratio) did not change with age. Peak Vcf correlated with heart rate and the decrease in heart rate with age resulted in the progressive fall in peak Vcf, while peak rate of left ventricular was thickening remained constant. The peak rate of increase in left ventricular cavity dimension in early diastole varied inversely with heart rate, but independently of cavity size, increasing throughout childhood. The peak rate of wall thinning also increased with age, correlating with wall thickness and not heart rate. Thus, age related increases in left ventricular cavity dimension and wall thickness during the rapid growth period of childhood occurred in such a way that left ventricular architecture (H/R ratio) remained unchanged. This may account for the constancy of regional and cavity systolic function. The greater dependence of diastolic cavity function on heart rate may be explained by the disproportionately greater effect of cardiac cycle length on the duration of diastole and systole. [ABSTRACT FROM PUBLISHER]

There has been much interest in the published reports as to the extent to which measured left ventricular diastolic properties are affected by the pericardium. In this study observations were made on 24 patients, seven days after cardiopulmonary bypass. Left ventricular dimensions were measured from echocardiographic recordings and left ventricular diastolic pressure assessed from measurements of isovolumic relaxation time. Pericardial pressure was measured directly using a small solid state transducer inserted into the pericardial space at the time of operation. Left ventricular diastolic properties were altered by either isometric handgrip or glyceryl trinitrate administration. Isometric handgrip produced an increase in cavity dimension at end-systole and diastole, with reduction in isovolumic relaxation time, suggesting an increase in left ventricular end-diastolic pressure; glyceryl trinitrate produced the reverse effect, with decreased cavity dimensions and prolongation of isovolumic relaxation time. These changes occurred in the absence of significant changes in pericardial pressure. We therefore conclude that even in the rather unusual conditions of the early postoperative period, when the sensitivity of pericardial pressure to small volume changes might be expected to be increased, substantial changes in left ventricular diastolic properties can occur without detectable alteration in pericardial pressure. [ABSTRACT FROM PUBLISHER]

The major cause of late mortality and morbidity after prosthetic valve replacement is thromboembolism. The nidus for initiation of thrombus formation has been blood metal interfaces, and a new valve--the St Jude prosthesis--has therefore been developed without any metal components. We have assessed echocardiographically in 27 patients the effects of this valve on left ventricular filling characteristics when inserted in the mitral position and compared the findings with those in patients having mitral valve replacement with Starr-Edwards or Björk-Shiley prostheses and with those in patients undergoing repair of the native mitral valve. Echocardiograms were recorded and digitised. Measurements were made of the peak rate of increase of dimension (dD/dt) and duration of rapid filling. Values for the St Jude valve were 13.2 +/- 3.4 cm/s and 160 +/- 40 ms, respectively. The peak rate of dD/dt increase was significantly greater than with either the Björk-Shiley valve or the Starr-Edwards valve and was comparable with findings in mitral valve repair. The duration of the rapid filling phase was not significantly different from control values but was less than that of the Starr-Edwards valve. This study indicates that the new St Jude medical valve is less obstructive than either the Björk-Shiley or Starr-Edwards prostheses. This together with its low thrombogenicity suggests that further trials of this new valve should be undertaken. [ABSTRACT FROM PUBLISHER]

M-mode echocardiograms were performed in 31 normal children in order to compare myocardial wall dynamics in different regions of the left ventricle. Tracings were recorded at the level of the mitral valve ring (level 1), near the tips of the mitral valve leaflets (level 2), and in the region of the papillary muscles (level 3) and were digitised. Fractional shortening increased from 31.7 per cent at level 1 to 36.5 per cent at level 3. Peak VCF and minor dimension lengthening rate were the same at all three levels, as were end-diastolic posterior wall thickness and peak systolic wall thickening rate. Striking regional differences, however, were seen in the extent of systolic posterior wall thickening which increased from 55 per cent at the base to 106 per cent at the papillary muscles, and in peak posterior wall thinning rate, which increased from 6.4 cm/s at the base to 10.0 cm/s at the papillary muscles. There was greater systolic inward movement of epicardium at level 1 than at levels 2 and 3. The septum thinned and thickened more slowly than did the posterior wall and did not show major differences between levels. Systolic reduction in minor dimension thus occurs largely by thickening of the wall at level 3 and by sphincter-like inward movement of the entire wall at level 1. These regional differences can be explained by a circumferential arrangement of myocardial fibres at the base of the heart and a more prominent longitudinal component towards the apex. Thus, non-uniformity of function is a prominent feature of the normal left ventricle and may reflect regional variation in its structure. [ABSTRACT FROM PUBLISHER]

We report a patient with a large coronary artery to bronchial artery anastomosis causing angina by coronary steal. Angina was refractory to medical treatment, but successfully relieved by surgical ligation of the anastomosis. [ABSTRACT FROM PUBLISHER]

The topography and specificity of fibre disarray and fibrosis in hypertrophic obstructive cardiomyopathy were determined in a histological study comprising 40 necropsy hearts--10 with hypertrophic cardiomyopathy, 10 with congestive cardiomyopathy, 10 with aortic valve stenosis, and 10 normal hearts. Seven standard regional sections were sampled from each heart and graded "double-blind" (tissue location and disease entity) for severity and extent of fibre dissarray and four distinct types of myocardial fibrosis. Statistical comparison of the severity and distribution of indices of fibre disarray and fibrosis within each group and between the normal and the disease groups showed that fibre disarray and fibrosis were qualitatively non-specific for hypertrophic cardiomyopathy. However, when fibre disarray was quantified (1) it was significantly increased in hypertrophic cardiomyopathy and allowed separation of hearts with hypertrophic cardiomyopathy from normal hearts and from those with congestive cardiomyopathy and aortic stenosis, (2) it did not vary significantly among sections of the left ventricle (that is, between the septum and the free wall) in hypertrophic cardiomyopathy, (3) it was closely associated with plexiform fibrosis, and (4) it varied independently of wall and septal thickness. Though the histogenesis of fibre disarray is unknown, it probably represents an exaggeration of a non-specific common pathway for many diverse pathophysiological processes. [ABSTRACT FROM PUBLISHER]

Three patients with mitral stenosis are described, in whom the haemodynamic findings at cardiac catheterisation were more suggestive of left ventricular myocardial disease, in that the left ventricular diastolic pressure was high and the mitral valve gradient small. However, their echocardiograms showed abnormal wall movement during diastole characteristic of severe inflow obstruction, with slow and protracted filling, and at operation mitral stenosis was confirmed. Left ventricular wall stress was estimated throughout the cardiac cycle in one patient, and the diastolic stress-strain relation shown to be abnormal. The effects of mitral stenosis on left ventricular function are complex, and are not explicable simply by reduction in size of the mitral orifice. [ABSTRACT FROM PUBLISHER]

In order to investigate the functional effects of mitral valve surgery, echocardiograms showing left ventricular dimension were recorded and digitised in 14 normal subjects and 129 patients after mitral valve surgery. Measurements were made of peak rate of increase of dimension (dD/dt) and duration of rapid filling, studies on left ventriculograms in 36 patients having shown close correlation between these values and changes in cavity volume. In 14 patients with mitral stenosis, peak dD/dt was reduced to 7-2 +/ 1-5 cm/s, and filling period prolonged to 330 +/- 65 ms, compared with normal (16-0 +/- 3-2 cm/s, and 160 +/- 50 ms, respectively), and after mitral valvotomy, these values improved significantly (10-4 +/- 2-7 cm/s and 245 +/- 55 ms). Characteristic abnormalities were found in 67 patients with mitral prostheses. Values for the Björk-Shiley (10-5 +/- 4-2 cm/s and 180 +/- 80 ms) and Hancock (10-3 +/- 3-7 cm/s, 245 +/- 80 ms) values were similar, and both superior to the Starr-Edwards (7-4 +/- 3-0 cm/s, 295 +/- 105 ms). Results after mitral valve repair in 30 cases were not significantly different from normal (14-4 +/- 5-0 cm/s, 170 +/- 50 ms). Values outside the 95 per cent confidence limits for the valve in question allowed diagnosis of value malfunction in 18 cases. The method is value in comparing different operative procedures and in following up patients after mitral valve surgery. [ABSTRACT FROM PUBLISHER]

Twenty patients were studied with simultaneous left ventricular cavity echocardiograms and apex cardiograms during the first two weeks after correction of severe aortic regurgitation. Endocardial echoes and apex cardiograms were digitized, so that left ventricular dimensions, their rates of change, and echo dimension-apex cardiogram relations could be studied. After aortic valve replacement, there was an early reduction in end-diastolic dimension, within 2 days, from 7-0 +/- 0-8 cm to 5-7 +/- 1-0 cm (P less than 0-001), while peak normalized shortening rate (peak Vcf) dropped from 1-9 +/- 0-6 to 1-4 +/- 0-6 S-1 (P less than 0-01), and remained unchanged for the remainder of the study. Immediately after operation, striking abnormalities of isovolumic contraction and, to a lesser extent, of early relaxation, could be seen, which regressed over 4 to 7 days, except in 2 patients who developed a low output state. These changes in left ventricular dimension, Vcf, and isovolumic contraction could not have been described by an single "measure" of left ventricular function. [ABSTRACT FROM PUBLISHER]

The addition of Doppler principles to two-dimensional echocardiography has revolutionized the noninvasive evaluation of valvular heart disease. Doppler techniques allow precise measurements of blood flow velocity at different locations in the heart and great vessels, so that many aspects of hemodynamics can now be measured noninvasively. These techniques are particularly useful for the quantitative assessment of valvular stenosis; both valve areas and transvalvular gradients may be determined. Doppler echocardiography (particularly with color flow mapping) is also useful for the qualitative assessment of valvular regurgitation. By understanding the uses and limitations of Doppler echocardiography, physicians may now confidently follow up patients with mild or moderate valvular disease with serial noninvasive studies, avoiding the risks of cardiac catheterization in many patients. [ABSTRACT FROM AUTHOR]