Abstract
This article describes the implementation of a simplified system that allows continuous 12-lead ECG monitoring from chest electrodes placed in clinically convenient locations.
The 12-lead electrocardiogram (ECG) is the diagnostic reference standard for evaluating cardiac rhythm and myocardial ischemia. The traditional 12-lead ECG system requires 10 electrodes that are strategically placed on the chest and the extremities (Figure 1). This lead configuration, however, is not practical for ambulatory patients in the telemetry setting. Subsequently, over the years, we have used a tool that captures limited and partial ECG data with just 1 or 2 views of the heart. This tool consists of a portable monitor (commonly referred to as a telemetry box), and 3 or 5 leads (depending on the type of telemetry that the institution has installed). Typically, 4 leads are attached to the patient’s torso (modified extremity leads), and the last lead acts as the precordial or “V” lead (Figure 2). This method has been used successfully for continuous cardiac monitoring.1
Telemetry monitoring was not designed, however, to obtain 12 views of the heart, but rather to derive continuous monitoring information from the 1 or 2 most commonly used ECG leads. Recent research and national guidelines on monitoring for myocardial ischemia2,–6 recommended continuous 12-lead ST-segment monitoring for at-risk patients because silent ischemia (without chest pain) is common and may not always be detected with the same leads. The busy environment of areas devoted to patients’ care, coupled with the need for frequent 12-lead ECG analysis, makes using a conventional, diagnostic 12-lead ECG device an impractical approach for continuous interpretation of cardiac rhythms and myocardial ischemia. What is most needed in the clinical monitoring environment is a continuous 12-lead ECG monitoring system to replace the traditional 3- to 5-lead telemetry monitoring system now used in most hospitals for continuous ECG monitoring.
In this article, we describe the clinical outcomes that occurred after implementation of a new 12-lead derived ECG system designed for continuous, bedside monitoring as a replacement for a traditional 3- to 5-lead system.