title: Increase in circadian variation after continuous-flow ventricular assist device implantation.
abstract: The circadian rhythm of varying blood pressure and heart rate is attenuated or absent in patients with severe heart failure. In 28 patients supported by a left ventricular assist device (LVAD) for at least 30 days, a restoration of the circadian rhythm was demonstrated by a consistent nocturnal decrease, and then increase, of the LVAD flow while at a constant LVAD speed. The return of the circadian rhythm has implications for cardiac recovery, and the observation indicates that the continuous-flow LVAD has an intrinsic automatic response to physiologic demands.
authors.affiliation: Division of Thoracic and Cardiovascular Surgery, Department of Surgery, University of Louisville, Louisville, KY 40202, USA. mark.slaughter@louisville.edu
authors.forename: Mark S
authors.initials: MS
authors.lastname: Slaughter
authors.forename: Michael S
authors.initials: MS
authors.lastname: Ising
authors.forename: Daniel
authors.initials: D
authors.lastname: Tamez
authors.forename: Gerry
authors.initials: G
authors.lastname: O'Driscoll
authors.forename: Neil
authors.initials: N
authors.lastname: Voskoboynikov
authors.forename: Carlo R
authors.initials: CR
authors.lastname: Bartoli
authors.forename: Steven C
authors.initials: SC
authors.lastname: Koenig
authors.forename: Guruprasad A
authors.initials: GA
authors.lastname: Giridharan
mesh_terms: D002319:Cardiovascular System / Q000503:physiopathology*; D002940:Circadian Rhythm; D004867:Equipment Design; D005260:Female; D006333:Heart Failure / Q000503:physiopathology* / Q000601:surgery*; D006353:Heart-Assist Devices; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies