Electrocardiography system of twelve leads for the study of the spatial variability of ventricular repolarization intervals

This work describes the design and operation of a electrocardiograph capable of acquiring simultaneous recordings of 12-lead for the study of the spatial variability of ventricular repolarization intervals. The electrocardiography system consists of an acquisition module with a dedicated channel for each lead with a circuit for detection of lead failure. Each channel has a gain of 1000, a CMRR of 90 dB and a bandwidth of 0.05 Hz to 150 Hz. It uses a isolated power supply and high isolation amplifiers at the output system. An additional stage of programmable amplification is added for signals conditioning before being acquired by the computer. The communication between these systems is by the USB port using a commercial data acquisition system (ADS) model Ni-USB 6211 with a resolution of 16 bits. The system display the 12-lead with a interface developed in LabVIEW and the data can be stored in ¿.xls files¿ for later processing.