Examining the effects of geometric uncertainty when computing endocardial and intracavitary probe potentials using a surface integral equation solution

The objectives of this study were to examine the effects of geometric uncertainty when computing intracavitary probe potentials and endocardial potentials via a forward and inverse solution, respectively. A cylindrical probe with 57 unipolar electrodes and 56 subendocardial electrodes were used to simultaneously record potentials within the left ventricular (LV) cavity and LV endocardium, respectively. Geometric uncertainty was examined by: (1) rotating the intracavitary probe surface from its known position within the LV cavity about its long (z) axis by -20/spl deg/ and +20/spl deg/; and (2) randomly perturbing the known LV endocardial geometry by /spl plusmn/5 mm. Quantitative comparison of results showed that the levels of geometric uncertainty used in this study did not have significant effects on the accuracy of the volume conductor model. Given the imaging modalities currently available, these levels of geometric uncertainty should be attainable when conducting studies of this nature.<>