APPENDIX B. NAC-MAD COMPOSITE DATASET B-1
MITRAL VALVE MECHANICS by Neil B. Ingels, Jr. and Matts Karlsson
APPENDIX B. NAC-MAD COMPOSITE DATASET
Here, we describe an attempt to model, as accurately as possible in 3-D space, the geometric
relationship between the various components of the left ventricle, the mitral valve, and the aortic valve during systole and diastole.
Datasets from two hearts were combined to develop this model:
• The first dataset was from a mitral valve study (nac09r03.1eg and nac09r03.1ig, datasets provided in this Appendix), with diastole defined at Frame 50 and systole at Frame 76. • The second dataset was from an aortic valve study (MAD09R01.1E, dataset provided in this
Appendix), with maximum diastole defined at Frame 50 and systole at Frame 42.
A Euclidian coordinate system was defined, with x-axis positive to the right, z-axis positive up, and y-axis positive into the plane of the paper.
Coordinate data from the diastolic mitral valve dataset sample (Frame 50) were first translated to place the annular “saddlehorn” Marker#22 (see Figure B.1) at the origin, then two rotations were performed to place the left ventricular apex (Marker#1) onto the negative z-axis. A final rotation was performed to place the lateral annulus (Marker#18) in the x-z plane. This process was repeated for the systolic mitral valve dataset sample (Frame 76).
Coordinate data from the diastolic aortic valve dataset sample (Frame 50) were first translated to place the annular “saddlehorn” Marker#23 (see Figure B.1) at the origin, then two rotations were performed to place the left ventricular apex (Marker#1) onto the negative z-axis. A further rotation was performed to place the lateral annulus (Marker#18) in the x-z plane. This process was repeated for the systolic aortic valve dataset sample (Frame 42).
The two datasets were then merged, resulting in two 3-D datasets (one for diastole, the other for
systole) that could be viewed from any angle, such as that displayed as Figures 1.1 and 1.2 in Chapter 01. These datasets
• COMPOSITE_NAC09R03_MAD09R01_DIASTOLIC_DATASET.dat • COMPOSITE_NAC09R03_MAD09R01_SYSTOLIC_DATASET.dat
are provided in this Appendix. Figure B.1 associates the column numbers in the merged datasets with the marker coordinates (e.g., the x-coordinate of nac Marker#24 is in column 70, its y-coordinate in column 71, and its z-coordinate in column 72; the x-coordinate of MAD Marker#16 is in column 205, its y-coordinate in column 206, and its z-coordinate in column 207, etc.).
APPENDIX B. NAC-MAD COMPOSITE DATASET B-2
MITRAL VALVE MECHANICS by Neil B. Ingels, Jr. and Matts Karlsson
