Correction of ECG variations due to non-standard electrode positions

Electrode positions for continuous monitoring of 12-lead ECG are different from those for recording a standard 12-lead ECG. To reduce noise and to minimize false alarms, proximal placement of the limb leads is preferred over the standard location at the wrists and ankles. These differences are often associated with apparent frontal QRS-axis shifts, disappearing Q-waves in the inferior leads and marked changes of R-amplitudes in leads I and II. These changes make it difficult to compare ECGs. This study presents a general and patient-specific method to correct for these changes.