Additional data on body surface potential maps of ventricular repolarization in normal adults.

To date most published studies on normal basic data of the potential distribution of cardiac activity have been restricted to ventricular depolarization. Only a few papers have dealt with ventricular repolarization in normal subjects. This is an attempt to establish the basic data of the body surface potential maps (BSPM) of ventricular repolarization in normal adults. BSPM of ventricular repolarization utilizing 87 electrodes through the heart potential map system designed by Toyama et al. were studied in 50 normal Chinese male adults. The following information on BSPMs was obtained: (1) In the initial phase of ventricular repolarization, the potential maximum was located on the precordial area and the potential minimum appeared on the right-superior portion of the back; (2) The movement of potentials was counterclockwise and stable during the later portion of the T loop; (3) The magnitudes of the potentials changed in a spindle pattern with the drifting of ventricular repolarization. They first increased and then decreased with the largest value being around the peak period of the T wave; (4) The absolute value was greater in the potential maximum than the potential minimum throughout ventricular repolarization. There was no "reversal" potential distribution pattern. This parameter may be of importance clinically; (5) There were usually multiple potential maxima and multiple potential minima during the ST segment and early phase of the T wave; (6) The largest potential maximum and potential minimum were 0.93 +/- 0.28 mV and 0.35 +/- 0.19 mV, respectively. The potential maximum and potential minimum at the peak T wave were 0.91 +/- 0.23 mV and 0.35 +/- 0.17 mV, respectively. Obviously, this study offers valuable basic data on the BSPM in normal adults and will be helpful to our understanding of the BSPM in various heart diseases.