[A new method of topical detection of accessory conduction pathways in patients with Wolff-Parkinson-White syndrome].

ECG mapping (90 leads) from the chest surface was used to examine 30 patients with the ventricular preexcitation syndrome. By applying endo- and epicardial mappings, 24, 3, and 1 patients were found to have one, two, and three accessory Kent's bundles, respectively. Two patients with Macheim's tract underwent surface mapping during the maximal preexcitation made via the nodoventricular tract. The authors consider the position of amplitude minimum equal to -0.09 +/- 0.03 mV, on the average, within the first 5 mc from the beginning of QRS complex (0 to 28 mc) to be a criterion for localizing the bundle by the surface mapping. To identify Kent's bundle with certainty by employing a small number of leads, the authors used unconventional (10-20) leads. Electrodes were placed in the x-ray topographoanatomic projection of the atrioventricular sulcus onto the chest.