Deriving the 12-lead electrocardiogram from four standard leads based on the Frank torso model

This paper proposes a lead method and a processing means for monitoring the 12-lead electrocardiogram (ECG) with four standard leads. Leads I, II of the M-L leads and leads V1, V6 of the chest leads are used to record the ECG signals. The ECG waveforms of leads V2 through V5 are derived from the input signals using the least squares method based on the Frank torso model. This method makes it possible to monitor the 12-lead ECG during ambulatory and long-term bedside monitoring. Examples recorded in the hospital environment show that the derived ECG waveforms can reproduce main features of the original signals, including the ST segment changes. The advantages of this method are discussed with compared to Dower´s EASI ECG.