Abstract：
:Coronary artery disease producing ischemic cardiomyopathy is the most frequent cause of left ventricular systolic dysfunction. Non-ischemic cardiomyopathies can also produce systolic dysfunction; they may be inherited as genetic disorders or occur sporadically. These coronary injuries have repercussions on the left ventricle producing changes on wall contractility, the shape of the cavity and also changes on ventricular function. This study is focused on the 2D echocardiograms of the left ventricle. Apical two chamber and four chamber view recordings were performed on normal and systolic dysfunction subjects. Individual frames were extracted for at least five cardiac cycles. After pre-processing these images, segmentation of the left ventricle was performed by Fuzzy systems. Then the volumes were measured by single and biplane methods along with the perimeter, short axis length and long axis length in each frame, from which the two indices Sphericity Index (SI) and Normalized Eccentricity Index (NEI) was determined. It was found that the diastolic phase is short in the case of systolic dysfunction, and its volume variation is not uniform as in the normal case. Also, in the case of systolic dysfunction, the span of either the long or short axis length variation is less than 0.5 cm. This depicts that akinesis is in the corresponding direction; the value of SI is less than 2 for systolic dysfunction. A sharp peak is seen at each systole point in the NEI plot and also its variation is smooth in subjects having LVEF > 45%, which is not the case for dysfunction.
journal_name
Australas Phys Eng Sci Medjournal_title
Australasian physical & engineering sciences in medicineauthors
Manivannan J,Reddy MR,Thanikachalam S,Kumar RAdoi
10.1007/BF03178864subject
Has Abstractpub_date
2005-03-01 00:00:00pages
51-5issue
1eissn
0158-9938issn
1879-5447journal_volume
28pub_type
杂志文章abstract：:Shear wave elasticity imaging (SWEI) has been used to measure the local tissue elasticity. The local tissue shear modulus can be reconstructed from the displacement field of shear waves using an algebraic Helmholtz inversion (AHI) equation or a time-of-flight (TOF)-based algorithm. The shear waves, which are generated...
journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
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更新日期：1989-12-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
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pub_type： 杂志文章,实务指引
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章,评审
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
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doi：
更新日期：1989-09-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章,评审
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
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更新日期：1999-12-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
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