title: The utility of the "notch" sign.
authors.forename: Kurt S
authors.initials: KS
authors.lastname: Hoffmayer
authors.forename: Nora
authors.initials: N
authors.lastname: Goldschlager
mesh_terms: D016477:Artifacts; D001282:Atrial Flutter / Q000175:diagnosis*; D003937:Diagnosis, Differential; D003951:Diagnostic Errors / Q000517:prevention & control*; D004562:Electrocardiography / Q000379:methods*; D006801:Humans; D017180:Tachycardia, Ventricular / Q000175:diagnosis*; D014693:Ventricular Fibrillation / Q000175:diagnosis*