title: Insertable cardiac monitors after cryptogenic stroke--a risk factor based approach to enhance the detection rate for paroxysmal atrial fibrillation.
abstract: OBJECTIVE
  Recently, the CRYSTAL AF trial detected paroxysmal atrial fibrillation (AF) in 12.4% of patients after cryptogenic ischaemic stroke (IS) or cryptogenic transient ischaemic attack (TIA) by an insertable cardiac monitor (ICM) within 1 year of monitoring. Our aim was (i) to assess if an AF risk factor based pre-selection of ICM candidates would enhance the rate of AF detection and (ii) to determine AF risk factors with significant predictive value for AF detection.
  
  
  METHODS
  Seventy-five patients with cryptogenic IS/TIA were consecutively enrolled if at least one of the following AF risk factors was present: a CHA2DS2-VASc score ≥4, atrial runs, left atrium (LA) size >45 mm, left atrial appendage (LAA) flow ≤0.2 m/s, or spontaneous echo contrast in the LAA. The electrocardiographic and echocardiographic criteria were chosen as they have been repeatedly reported to predict AF; the same applies for four of the six items of the CHA2DS2-VASc score. The study end-point was the detection of one or more episodes of AF (≥2 min).
  
  
  RESULTS
  Seventy-four patients underwent implantation of an ICM; one patient had AF at the date of implantation. After 6 months, AF was detected in 21/75 patients (28%), after 12 months in 25/75 patients (33.3%). 92% of AF episodes were asymptomatic. LA size >45 mm and the presence of atrial runs were independently associated with AF detection [hazard ratio 3.6 (95% confidence interval 1.6-8.4), P = 0.002, and 2.7 (1.2-6.7), P = 0.023, respectively].
  
  
  CONCLUSIONS
  The detection rate of AF is one-third after 1 year if candidates for an ICM after cryptogenic IS/TIA are selected by AF risk factors. LA dilation and atrial runs independently predict AF.
authors.affiliation: Department of Neurology and Stroke, and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Poli
authors.affiliation: Department of Neurology and Stroke, and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Diedler
authors.affiliation: Department of Neurology and Stroke, and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Härtig
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Götz
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Bauer
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Sachse
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Müller
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Müller
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Stimpfle
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Duckheim
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Steeg
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Eick
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Schreieck
authors.affiliation: Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Gawaz
authors.affiliation: Department of Neurology and Stroke, and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Ziemann
authors.affiliation: Department of Neurology and Stroke, and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.|Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: C S
authors.initials: CS
authors.lastname: Zuern
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000000981:diagnostic imaging; D004562:Electrocardiography / Q000295:instrumentation*; D005260:Female; D006801:Humans; D002546:Ischemic Attack, Transient / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation*; D012307:Risk Factors; D020521:Stroke / Q000175:diagnosis* / Q000000981:diagnostic imaging; D014463:Ultrasonography
keywords: atrial fibrillation; cryptogenic TIA; cryptogenic stroke; insertable cardiac monitor