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STRESS AND STRAIN DISTRIBUTIONS IN THE ISCHEMIC MYOCARDIAL CANINE HEART |
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| รหัสดีโอไอ | |
| Creator | Tipapon Khamdaeng, Pradit Terdtoon |
| Title | STRESS AND STRAIN DISTRIBUTIONS IN THE ISCHEMIC MYOCARDIAL CANINE HEART |
| Publisher | Faculty of Engineering and Agro-Industry Meajo University |
| Publication Year | 2559 |
| Journal Title | Maejo Engineering and Agro Industry Journal |
| Journal Vol. | 1 |
| Journal No. | 1 |
| Page no. | 29-35 |
| Keyword | In vivo, Myocardial ischemia, Pseudostrain-energy function, Transversely isotropic constitutive equation, Ultrasound crystals |
| ISSN | 2408-2297 |
| Abstract | The dysfunction of the left ventricular (LV) wall causes the death of a large amount of people worldwide each year. One of the most dangerous diseases is heart attack originating from ischemia which results in damage of LV myocardium due to insufficient blood supply from coronary arteries; thus, the mechanical property changes which take place need to be determined in order to specify some indices for diagnosis in clinical treatment. In-vivo invasive assessment using a pressure catheter and ultrasound crystals was conducted in a mongrel male dog, weighing 27.6 kg, to determine LV pressure and LV myocardial deformation, respectively. The regional stress and strain were respectively calculated based on the thick-walled theory and the movement of the tetrahedron-shaped crystals implanted at an anterior-lateral wall region of LV myocardium. Normal and myocardial ischemic canine heart was progressively induced by left anterior descending (LAD) coronary flow reduction. In conclusion, the LV myocardial mechanics model was established, incorporating the active transversely isotropic constitutive relations, in terms of a new polynomial form of pseudostrain-energy function (W). The stresses and strains can be calculated at any radial location in the LV myocardium. The normal myocardium undergoes wall thickening, systolic shortening, and right-handed torsion; in contrast, the graded ischemic canine heart at 80% and 100% LAD coronary occlusion levels undergoes wall thinning, systolic stretching, and left-handed torsion. |
