Patent ID: 7613506

Claim:
A method of deriving a standard 12-lead electrocardiogram, comprising: attaching four first electrodes on the vicinity of a lower right end of a right clavicle, the vicinity of a lower left end of a left clavicle, the vicinity of a position on a right anterior axillary line at the level of a right lowermost rib, and the vicinity of a position on a left anterior axillary line at the level of a left lowermost rib of a living body, so as to correspond to limb leads of the standard 12-lead electrocardiogram; attaching two second electrodes on such positions of the living body that correspond to a lead V 2 and a lead V 4 of chest leads of the standard 12-lead electrocardiogram; measuring a first electrocardiogram data set corresponding to a lead I and a lead II of the standard 12-lead electrocardiogram with the first electrodes; measuring a second electrocardiogram data set including the lead V 2 and the lead V 4 with the second electrodes; calculating an instantaneous electromotive force vector (a heart vector) based on the first electrocardiogram data set, the second electrocardiogram data set, and predetermined first lead vectors of the lead I, the lead II, the lead V 2 and the lead V 4 ; calculating a third electrocardiogram data set including a lead V 1 , a lead V 3 , a lead V 5 and a lead V 6 of the chest leads based on the heart vector and predetermined second lead vectors of the lead V 1 , the lead V 3 , the lead V 5 and the lead V 6 ; calculating a fourth electrocardiogram data set corresponding to a lead III, a lead aVR, a lead aVL and a lead aVF of the standard 12-lead electrocardiogram based on the first electrocardiogram data set; and deriving the standard 12-lead electrocardiogram based on the first electrocardiogram data set, the second electrocardiogram data set, the third electrocardiogram data set and the fourth electrocardiogram data set.