Case 3 Triangulated Torso and Heart Geometry

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These files, and the notes below, were prepared by A. van Oosterom and P. van Dam. The geometry files are text files. Matlab code for reading and manipulating the .tri files is also provided here.

Geometry (.tri) files: (ascii files)

All the above: consistent coordinate system; heart in natural position

In addition, here is the model containing the nodes that should be referenced for challenge event 5:

Auxiliary files

Descriptive trailers are included in these files:

These files are described below:

Using .tri files in Matlab

Each .tri file can be opened in Matlab as


Strip the first column, which contains vertex/triangle labels. VER are coordinates of all nodes of the mesh, and ITRI are ordered triples of the triangles.

The ECG potential data may be imported in Matlab by using:


After stripping the first 3 columns by:

the potentials (units 1 microV) are a matrix of potential data, with the rows at 1 ms intervals. The first 3 columns are leads Vr, Vl, and Vf (non-augmented amplitudes!); the next 120 columns are the potentials at the 120 electode array; and the remaining columns are the potentials at a regular 352 array.

Potentials at all 370 nodes representing the thorax can be computed by using the transfer matrix:

which yields a Laplacian based interpolation (see intripol.m):
The file get_370_lead_signals.m shows how to "generate" the potentials at the 370 nodes of the torso model starting with the data file and the auxiliary files.

Finally, the files savemat.m and savetri.m are scripts for storing any similar output data.

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