title: A supraventricular tachycardia showing alternation of the QRS interval.
authors.affiliation: Department of Cardiology, Groene Hart Ziekenhuis, Bleulandweg 10, 2803, HH, Gouda, the Netherlands, r.j.van_bommel@lumc.nl.
authors.forename: R J
authors.initials: RJ
authors.lastname: van Bommel
authors.forename: E G
authors.initials: EG
authors.lastname: Weijers
authors.forename: H J
authors.initials: HJ
authors.lastname: Wellens