الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Previous epidemiological studies have demonstrated increased prevalence of diabetes mellitus in heart failure populations, and this increased prevalence is seen particularly in heart failure patients with normal LVEF.
However, LVEF is a relatively insensitive measure of LV systolic function compared to strain and strain rate imaging, especially in the context of subclinical LV systolic dysfunction. As the LV myocardial architecture is a complex array of longitudinally and circumferentially orientated fibres located predominately in the epicardium/endocardium and mid-wall respectively, multidirectional analyses of longitudinal, circumferential and radial function allow understanding of regional LV myocardial functional changes in subclinical diabetic heart disease Diastolic dysfunction has been described as an early stage in diabetic heart disease progression in patients with normal LVEF, isolated diastolic dysfunction is usually rare and when present, it often associated with subclinical systolic dysfunction. Systolic dysfunction might be initially apparent in the longitudinal direction, because subendocardial fibres, which are the ones more vulnerable to myocardial ischaemia and fibrosis, are longitudinally oriented.
Several studies have demonstrated that subclinical systolic longitudinal dysfunction can be identified using tissue Doppler imaging in patients with diabetes, and diastolic dysfunction. However, this method provides information in a single direction from a fixed transducer position. This method is also dependent on the angle between the beam and myocardial motion. In contrast, 2DSTE has the advantage that it allows the measurement of all principal LV strains in an angle independent manner, thus eliminating the major limitation of tissue doppler imaging.
The aim of this study is to identify Subclinical left ventricular (LV)systolic dysfunction by a reduction in longitudinal function, which can be assessed using 2D speckle tracking echocardiography (STE).
The present study included 50 patients with type 2 diabetes mellitus and 20 subjects age matched served as control. And all were subjected to the following:
1. Full history evaluation.
2. Full clinical examination.
3. Resting ECG.
4. Fasting blood glucose level.
5. Glycosylated HB.
6. Total serum cholesterol and triglycerides.
7. Trans-Thoracic Echocardiography: the examination of systolic function regarding measurement of EF (%) and FS (%), diastolic function
assessment through measurement of E wave, A wave, E/A ratio and deceleration time.
8. Pulsed tissue Doppler imaging of systolic function, regarding
measurement of Sm velocity and diastolic function assessment through
measurement of Em, Am and IVRT at miteral annulus level.
9. Strain and strain rate parameters were measured by using GE Vivid 9
echocardiography machine, through an off line analysis by using 2 D
Speckle tracking imaging, we measured global and regional peak
systolic strain, global and regional peak systolic strain rate, global and
regional early diastolic strain rate and global and regional late
diastolic strain rate.
Subject with the following condition were excluded from the study:
10- Coronary artery disease based on resting ECG.
11- Valvular or congenital heart disease.
12- Impaired LV systolic function (ejection fraction <60%, LVH or any
Regional wall motion abnormality).
13- More than mild (grade 1) arterial hypertension.
14- Conduction or rhythm disturbances.
15- Pericardial diseases.
16- Endocrine or other systems diseases than D.M.
17- Any febrile condition or infectious diseases.
18- Smokers.
In the present study conventional Doppler parameters using E/A ratio
and deceleration time failed to show diastolic dysfunction in the group of type
2 diabetes mellitus.
Pulsed wave tissue Doppler imaging unlike conventional Doppler help to
demonstrate diastolic dysfunction in the diabetic group through increase value
of E/Em ratio and IVRT.
As for strain and strain rate, by using 2 D Speckle tracking imaging,
through an off line analysis we measured global and regional longitudinal
peak systolic strain, global and regional peak systolic strain rate, global and
regional early diastolic strain rate and global and regional late diastolic strain
rate and comparing these measures with the controls, we found that, these
parameters were impaired in the diabetic group.
In the present study, there was no correlation between the age and the
studied parameters in type 2 diabetes mellitus by using 2 D Speckle tracking
imaging study. But there was highly significant negative correlation between
the studied parameters and the duration of type 2 diabetes mellitus.
In the present study there was significant negative correlation between
global and regional longitudinal strain and strain rate and E/Em ratio confirms
the link between systole and diastole.
Regarding the correlation between the value of HbA1C in the group of
diabetes mellitus and the studied parameters, strain and strain rate was more
valuable than conventional Doppler in finding negative correlation between
systolic and diastolic function and the value of HbA1C, however conventional
Doppler did not find any correlation between systolic and diastolic function
and the value of HbA1C.
The result of the present study have demonstrated the presence of
subclinical left ventricular systolic and diastolic dysfunction in patients with
type 2 diabetes mellitus, with no diabetic related complication. Despite a
normal LV EF and normal LV diastolic measures with 2 D Echocardiography,
the diabetic patients showed impairment of LV longitudinal strain and strain
rate.
The presence of diabetes was an independent predictor of impairment of
LV longitudinal strain and strain rate and that give more sensitivity to strain
and strain rate over conventional Doppler in earlier detection of systolic
function.