الفهرس 
Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
Speckle Tracking Echocardiography is a novel technique to assess LA function that allows angle independent, comprehensive and accurate assessment of myocardial motion. It is shown to overcome the limitation of TDI in registering the motion of tethered myocardium and other intracardiac structure.
Increased LA diameter and volumes (LA maximum, minimum and pre-A) in patients with systolic heart failure.
Decreased LA reservoir, conduit and systolic functions measured by strain and volumetric parameters in heart failure patients with reduced LV ejection fraction.
There is negative correlation between clinical symptoms of heart failure according to New York Heart Association and left atrium function.
Left atrial strain positively correlates to left ventricular strain in patients with systolic heart failure.
There was positive correlation between LA function assessed by strain and parameters of LV diastolic function namely; SrLE and SrLA, in patients with systolic heart failure.
Study Limitation
1- Relatively small number of the study population.
2- Time factor. There was no specific time interval between occurrence of HF and beginning of the study.
3- Non accurate selection of the patient group according to the cause of heart failure whether its ischemic or idiopathic cardiomyopathy.
4- No follow up of the patients for incidence of intra-atrial thrombus or atrial fibrillation.
Heart failure is a common disease affecting approximately 5 million in the united states, and it occurs predominately in the elderly, with almost 80% of cases occurs in patients over the age of 65. The magnitude of the problem can’t be assessed, because reliable population-based data on the prevalence, incidence, and prognosis are lacking. Nevertheless, several studies have found that CHF is associated with 2 year mortality rate of approximately 45-50%, which approaches that of many malignancies.
Left atrial function, in a close interdependence with LV function, plays a key role in maintaining an optimal cardiac performance. The LA modulates LV filling through its reservoir, conduit, and booster pump function, whereas LV function influences LA function throughout the cardiac cycle. The LA can act to increase LA pressure (in significant atrial disease) and can react to increased LV filling pressure (in significant ventricular disease).
Speckle-tracking echocardiography is a new noninvasive ultrasound imaging technique that allows for an objective and quantitative evaluation of global and regional myocardial function independently from the angle of insonation and from cardiac translational movements. Nonetheless, although this new technique was introduced for the exclusive analysis of LV function, several studies have recently extended its applicability to other cardiac chambers, such as the left atrium.
The aim of the present investigation was to assess the left atrial function by 2D speckle tracking in patients with systolic heart failure . The study comprised 80 randomly selected persons, thirty five with ejection fraction < 50%, thirty five with EF more than 50% and symptomatic heart failure and 10 of normal individuals. Both groups were subjected to conventional and 2D speckle tracking echocardiography to assess the left atrial function.
Left atrial volumes were assessed at end of systole (max AV), at mitral valve closure (min AV) and just before atrial contraction (pre-A). Left atrial reservoir, conduit and systolic functions were assessed throughout the cardiac cycle using both volumetric and strain measurements. LV global strain and Strain rate were performed, and SrLs, SrLE and SrLA were measured. The results revealed increased left atrial diameter and volumes in patients with systolic heart failure compared to the control group. Also there was decrease in left atrial reservoir, conduit and systolic functions in patients with systolic heart failure. This was supported by decreased left atrial strain and volumetric parameters in both systole and diastole in those patients. It was also found that there was negative correlation between symptoms of heart failure and left atrial function. In addition, the study demonstrated decreased LA function with increased severity of diastolic dysfunction in patients with systolic heart failure.