The 12-lead Electrocardiogram (ECG) is a diagnostic tool used routinely to assess the cardiac state of patients. It must be recorded in a standard fashion, by positioning 10 electrodes at precise locations on the patient’s torso. It has, however, been observed that medical personnel often misplace these electrodes. Despite this, students rely on ECG textbooks that do not address or include material regarding the effects of electrode misplacement. Moreover, more advanced pedagogic tools such as mannequins do not allow electrodes to be arbitrarily moved and therefore cannot be used to demonstrate such effects. As a result, we designed an Electrode Misplacement Simulator (EMS). The EMS is an intuitive Web application that allows students and researchers to freely move each of the electrodes whilst viewing the effects this has on the 12-lead ECG. The 12-lead ECG generated from the misplaced electrodes are calculated by the EMS from real data recorded from a patient. It was then decided to use the EMS for research purposes to quantify just how much the ECG is affected when a commonly erred electrode configuration is used. With the EMS and data recorded from 232 patients, 464 12-lead ECGs were generated. This dataset consisted of 232 ECGs generated from the correct electrode positions and 232 ECGs generated from the incorrect electrode positions. Statistics provided by the EMS were used to quantify the differences in the signals between the correct recordings and the corresponding incorrect recordings. A random sample of these ECGs (150: 75 correct and 75 incorrect) were then interpreted and serially compared by two different clinicians. The results show that lead V2 is affected the most when misplaced and that there is a reasonable chance (16%-24%) that the clinician’s interpretation will be different if the ECG is recorded incorrectly. It can be concluded that the results justify the use of the EMS and other methods for educating students about the effects of electrode misplacement.
|Publisher||Higher Education Academy|
|Publication status||Published (in print/issue) - 2011|