Estimation of propagation velocity of gastric electrical activity using LMSTDE.

The least mean square time delay estimate (LMSTDE) algorithm is independent of the prior knowledge of signals and noises. Under the LMS criterion, the best estimate is acquired by automatic adjusting related parameters. In this paper, we applied LMSTDE to estimate the propagation velocities of four-channel gastric myoelectrical recordings that were obtained from implanted gastric serosal electrodes in three gastroparetic patients. The performance of the method was investigated using computer simulations. The results of this paper showed that the average velocities in gastroparetic patients are slower than in normal subjects. The propagation of gastric slow wave is along the greater curvature from upper 1/3 of the corpus toward the pylorus but the variability of the propagation velocity does not increase monotonously.