Introduction to monitoring the electrocardiogram.
D001145:Arrhythmias, Cardiac / Q000175:diagnosis; D004562:Electrocardiography; D006801:Humans; D006934:Hypercalcemia / Q000175:diagnosis; D006947:Hyperkalemia / Q000175:diagnosis; D006996:Hypocalcemia / Q000175:diagnosis; D007008:Hypokalemia / Q000175:diagnosis; D008991:Monitoring, Physiologic; D009203:Myocardial Infarction / Q000175:diagnosis