Publications by authors named "Nastaran Shahmansouri"

Sudden failure and rupture of the tissue is a rare but serious short-term complication after the mitral valve surgical repair. Excessive cyclic loading on the suture line of the repair can progressively damage the surrounding tissue and finally cause tissue rupture. Moreover, mechanical over-tension, which occurs in a diseased mitral valve, gradually leads to tissue floppiness, mitral annular dilation, and leaflet rupture.

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An aortic aneurysm is a lethal arterial disease that mainly occurs in the thoracic and abdominal regions of the aorta. Thoracic aortic aneurysms are prevalent in the root/ascending parts of the aorta and can lead to aortic rupture resulting in the sudden death of patients. Understanding the biomechanical and histopathological changes associated with ascending thoracic aortic aneurysms (ATAAs), this study investigates the mechanical properties of the aorta during strip-biaxial tensile cycles.

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Introduction: Ex vivo measurement of ascending aortic biomechanical properties may help understand the risk for rupture or dissection of dilated ascending aortas. A validated in vivo method that can predict aortic biomechanics does not exist. Speckle tracking transesophageal echocardiography (TEE) has been used to measure ventricular stiffness; we sought to determine whether speckle TEE could be adapted to estimate aortic stiffness in vivo and compare these findings with those obtained by ex vivo tissue measurements.

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Ascending thoracic aortic aneurysms (ATAAs) can lead to a dissection or rupture of the aorta, causing death or disability of the patients. Surgical interventions used to treat this disease are associated with risks of mortality and morbidity. Several studies have investigated the rupture mechanisms of ATAAs; however, underlying reasons behind aortic rupture (failure) have not been fully elucidated and further investigations are necessary.

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Surgical interventions are used to manage severe complications of heart valve diseases and to prevent the eventual rupture of an aortic aneurysm. Soft-tissue allografts, xenografts, and prosthetic grafts are used in these interventions; however, there are pre-surgical difficulties and post-surgical complications in using these grafts. One of these is the rupture potential of cryopreserved allografts at the time of transplantation and/or after the thawing process for the cryopreserved tissue.

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