Estimation of epicardial activation maps from intravascular recordings

Multielectrode catheters provide a percutaneous means of recording activati on near the epicardium but only for a relatively small number of sites that are restricted to the major coronary vessels. We have applied a statistica l signal processing technique to estimate the value of activation time over the entire epicardium (490 sites) from leadsets consisting of 4 to 40 sire s aligned with major branches of the coronary veins. We tested this method using data from high-resolution epicardial mapping from six dog hearts and 153 activation sequences. A study including data from both normal and infar cted dog hearts yielded estimates of activation time, with mean correlation coefficients ranging from 0.97 to 0.84 and achieved localization of earlie st site of activation to within 3 to 15 mm, depending on training parameter s and leadset. These results suggest that with 10 to 15 catheter-mounted el ectrodes, it may be possible to reconstruct epicardial activation maps from percutaneous recordings.