title: Letter: Interpretation of findings using Holter ECG recordings.
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis*; D001466:Barium Sulfate; D004562:Electrocardiography / Q000295:instrumentation*; D004733:Enema / Q000009:adverse effects*; D006801:Humans; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation
chemical_list: D001466:Barium Sulfate