Date of download: 6/21/2016 Copyright © ASME. All rights reserved. From: In Vitro Dynamic Strain Behavior of the Mitral Valve Posterior Leaflet J Biomech Eng. 2005;127(3): doi: / An example of principal angle of the deformation of the central region of the posterior leaflet during valve closing and opening. It deviated slightly from 90°. This deviation rarely went above 20°, demonstrating that the principal angle usually aligned with the radial and circumferential directions. Figure Legend:

Date of download: 6/21/2016 Copyright © ASME. All rights reserved. From: In Vitro Dynamic Strain Behavior of the Mitral Valve Posterior Leaflet J Biomech Eng. 2005;127(3): doi: / An example of the shear angle α for the posterior leaflet, which represents the change in angle that two originally orthogonal lines undergo with deformation. The shear angle α was generally small (usually less than 5°), suggesting that the differences between the principal stretches and the stretch values resolved into the collagen fiber preferred directions were sufficiently small and did not yield any new information. Figure Legend:

Date of download: 6/21/2016 Copyright © ASME. All rights reserved. From: In Vitro Dynamic Strain Behavior of the Mitral Valve Posterior Leaflet J Biomech Eng. 2005;127(3): doi: / A representative example of the major and minor principal stretches and stretch rates during valve closing and opening in the normal PM position. The principal stretches demonstrate a rapid rise early in valve closure, followed by a plateau in systole, suggesting that the collagen fibers were fully straightened. Principal stretches decreased to the original state when the valve opened. There was a significant difference between the major and minor principal stretches. The peak major principal stretch rate was higher than the minor principal stretch rate during both valve closing and opening. The peak major principal stretch rate was higher during the valve unloading (i.e., opening) process than during valve loading (i.e., closing) process. Figure Legend:

Date of download: 6/21/2016 Copyright © ASME. All rights reserved. From: In Vitro Dynamic Strain Behavior of the Mitral Valve Posterior Leaflet J Biomech Eng. 2005;127(3): doi: / An example of the areal strain and areal strain rate during valve closing and opening in the normal papillary muscle position. The areal strain demonstrated a similar trend as principal stretches, and there was a plateau when the valve was closed. Figure Legend:

Date of download: 6/21/2016 Copyright © ASME. All rights reserved. From: In Vitro Dynamic Strain Behavior of the Mitral Valve Posterior Leaflet J Biomech Eng. 2005;127(3): doi: / An example of the transmitral pressure versus areal strain during the valve closure in the normal papillary muscle positions. These results show a dramatic stiffening of the central region of the posterior leaflet. Figure Legend:

Date of download: 6/21/2016 Copyright © ASME. All rights reserved. From: In Vitro Dynamic Strain Behavior of the Mitral Valve Posterior Leaflet J Biomech Eng. 2005;127(3): doi: / An example of SALS experiment results were superposed on the posterior leaflet, showing the mapping of preferred fiber orientation on the posterior leaflet. The posterior leaflet generally had a more irregular structure. The preferred fiber orientation is relatively uniform in the central region of the posterior leaflet. Figure Legend:

Date of download: 6/21/2016 Copyright © ASME. All rights reserved. From: In Vitro Dynamic Strain Behavior of the Mitral Valve Posterior Leaflet J Biomech Eng. 2005;127(3): doi: / The Georgia Tech left heart simulator and flow loop were driven by a bladder pump. A data acquisition system recorded the transmitral pressure and flow rate. Two high speed cameras placed at an angle in the atrial side of the mitral valve recorded the marker array. Images and transmitral pressures were synchronized with a trigger signal from the pulse generator. Figure Legend:

Date of download: 6/21/2016 Copyright © ASME. All rights reserved. From: In Vitro Dynamic Strain Behavior of the Mitral Valve Posterior Leaflet J Biomech Eng. 2005;127(3): doi: / A marker array on the central region of the posterior leaflet between the annulus and the coaptation line. A sequence of images from camera A and B covering the period of valve closing and opening were recorded, digitized, and analyzed later to determine the principal stretches and areal strains of the central area of the posterior leaflet. Figure Legend:

Date of download: 6/21/2016 Copyright © ASME. All rights reserved. From: In Vitro Dynamic Strain Behavior of the Mitral Valve Posterior Leaflet J Biomech Eng. 2005;127(3): doi: / An example of flow rate and transmitral pressure of the tested valve. The valve closed and opened between 0 and 0.35 s. The valve closed during 0 s and 0.15 s, the valve was closed between 0.15 s and 0.25 s, and the valve opened during 0.25 s and 0.35 s. The transmitral pressure increased only a few mm Hg before 0.1 s. The mitral flow was negative during valve closure, which is predominantly the closing volume. It increased up to 15L∕min during valve opening. Figure Legend:

Date of download: 6/21/2016 Copyright © ASME. All rights reserved. From: In Vitro Dynamic Strain Behavior of the Mitral Valve Posterior Leaflet J Biomech Eng. 2005;127(3): doi: / Three dimensional surface fit results for the marker array area of the posterior leaflet, with t=0 defined as the first frame where all markers are visible. Vectors represent the principal stretch direction and color fringe local major principal stretch magnitude (PS1). Here, the u and v axes are coincident with the circumferential and radial axes, respectively. Figure Legend: