Abstract：
:Left ventricular assist device (LVAD) support unloads left ventricular (LV) pressure and volume and decreases wall stress. This study investigated the effect of systematic LVAD unloading on the 3-dimensional myocardial wall stress by employing finite element models containing layered fiber structure, active contractility, and passive stiffness. The HeartMate II(®) (Thoratec, Inc., Pleasanton, CA) was used for LV unloading. The model geometries and hemodynamic conditions for baseline (BL) and LVAD support (LVsupport) were acquired from the Penn State mock circulatory cardiac simulator. Myocardial wall stress of BL was compared with that of LVsupport at 8,000, 9,000, 10,000 RPM, providing mean pump flow (Q(mean)) of 2.6, 3.2, and 3.7 l/min, respectively. LVAD support was more effective at unloading during diastole as compared to systole. Approximately 40, 50, and 60% of end-diastolic wall stress reduction were achieved at Q(mean) of 2.6, 3.2, and 3.7 l/min, respectively, as compared to only a 10% reduction of end-systolic wall stress at Q(mean) of 3.7 l/min. In addition, there was a stress concentration during systole at the apex due to the cannulation and reduced boundary motion. This modeling study can be used to further understand optimal unloading, pump control, patient management, and cannula design.
journal_name
Med Biol Eng Computjournal_title
Medical & biological engineering & computingauthors
Jhun CS,Sun K,Cysyk JPdoi
10.1007/s11517-014-1205-3subject
Has Abstractpub_date
2014-12-01 00:00:00pages
1031-40issue
12eissn
0140-0118issn
1741-0444journal_volume
52pub_type
杂志文章abstract：:Over a period of some years, the components of a system for discerning erosion on children's teeth have been progressively developed, for use in an extensive project seeking correlations between erosion and various perceived risk factors. The aim was the detection of minute levels of erosion, based on mappings of the ...
journal_title：Medical & biological engineering & computing
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journal_title：Medical & biological engineering & computing
pub_type： 杂志文章,评审
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