An Unusual Cause of Electrocardiographic Artefact: A Patient's Warming Blanket

In electrocardiography, an electrocardiographic (ECG) artefact is used to indicate a misleading or confusing alteration in data or observation not arising from the heart. Although technological advancements have produced monitors that may provide accurate data and reliable heart rate alarms, interferences of the displayed electrocardiogram such as (but not limited to) electrical interference by outside sources, electrical noise from elsewhere in the body, poor contact and machine malfunction continue to occur. Artefacts are extremely common, and knowledge regarding them is necessary to prevent misinterpretation of a heart's rhythm, which can often lead to unnecessary and unwarranted diagnostic and interventional procedures. Here we report a case of ECG artefacts that occur owing to a patient's warming blanket and its consequences.