title: The mystery of the fourth beat.
authors.affiliation: St Antonius Hospital, Nieuwegein, The Netherlands. floris.s.van.den.brink@gmail.com.
authors.forename: F
authors.initials: F
authors.lastname: van den Brink
authors.affiliation: St Antonius Hospital, Nieuwegein, The Netherlands.
authors.forename: I
authors.initials: I
authors.lastname: Frenaij
authors.affiliation: St Antonius Hospital, Nieuwegein, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: van Tooren