Constructing a multichannel electrocardiography system from a few standardized, high-level components

Multichannel systems for electrocardiography must be able to reliably measure and store large numbers of simultaneous low-frequency analog signals, while providing high gain, protection against defibrillation, and adequate electrical isolation. In the past, these specifications have been unique enough to force investigators to build up their systems from thousands of basic electronic components, like commercial integrated circuit amplifiers, power supplies, and analog-to-digital converters. It can take years to design, build, and debug a cardiac mapping system from basic components. The long development time and the need for specialized training to design from basic components forced some investigators to buy complete mapping systems or simply to avoid multichannel mapping. However, there is now another approach for these investigators. Recent advances in electronics, most notably the advent of high-speed open-industry bus standards, have made it possible to construct multichannel systems from just a few high-level off-the-shelf (standardized) components. The off-the-shelf approach can be used by most investigators without specialized training. This article describes the high level components of an off-the-shelf mapping system and the selection of those components for a particular application.