title: Effect of exercise on cycle length in atrial flutter.
abstract: OBJECTIVE
  To examine the effect of exercise on cycle length in atrial flutter.
  
  
  METHODS
  15 patients with chronic atrial flutter. Seven patients were taking digoxin and six verapamil; two were not taking medication.
  
  
  METHODS
  All patients underwent bicycle ergometry. Flutter cycle length was measured at rest and at peak exercise.
  
  
  RESULTS
  Mean flutter cycle length increased from 245 ms to 256 ms (P = 0.002). Six patients developed 1:1 atrioventricular conduction. Significant increases in flutter cycle length were observed irrespective of development of 1:1 atrioventricular conduction and use of digoxin and verapamil.
  
  
  CONCLUSIONS
  Exercise prolongs flutter cycle length. This effect would promote development of 1:1 atrioventricular conduction during exercise, causing inordinately high ventricular rates.
authors.affiliation: Department of Cardiology, University Hospital Groningen, The Netherlands.
authors.forename: M P
authors.initials: MP
authors.lastname: van den Berg
authors.forename: H J
authors.initials: HJ
authors.lastname: Crijns
authors.forename: B M
authors.initials: BM
authors.lastname: Szabó
authors.forename: J
authors.initials: J
authors.lastname: Brouwer
authors.forename: K I
authors.initials: KI
authors.lastname: Lie
mesh_terms: D000328:Adult; D001282:Atrial Flutter / Q000188:drug therapy / Q000503:physiopathology*; D004077:Digoxin / Q000627:therapeutic use; D004562:Electrocardiography; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D014700:Verapamil / Q000627:therapeutic use
chemical_list: D004077:Digoxin; D014700:Verapamil