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Graz Study on the Risk of Atrial Fibrillation (GRAF)

This study is ongoing, but not recruiting participants.
ClinicalTrials.gov Identifier:
First Posted: October 28, 2011
Last Update Posted: December 22, 2015
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by (Responsible Party):
Frank R Heinzel, MD, PhD, Medical University of Graz
October 23, 2011
October 28, 2011
December 22, 2015
November 2011
May 2015   (Final data collection date for primary outcome measure)
Time to first diagnosis of atrial fibrillation [ Time Frame: 12 months ]
Same as current
Complete list of historical versions of study NCT01461434 on ClinicalTrials.gov Archive Site
  • Time to change in therapy based on the diagnosis of atrial fibrillation [ Time Frame: Baseline (0 months), 1,2,3,4,5,6,9 and 12 months ]
  • Hospitalizations [ Time Frame: 12 months ]
  • Change in NTproBNP serum level associated with occurrence of atrial fibrillation [ Time Frame: Baseline (0 months), 1,2,3,4,5,6,9 and 12 months ]
  • Death [ Time Frame: 12 months ]
  • Stroke [ Time Frame: 12 months ]
Same as current
Not Provided
Not Provided
Graz Study on the Risk of Atrial Fibrillation
Randomized Controlled Trial to Evaluate Implanted Event Recorders for the First Diagnosis of Atrial Fibrillation in High-risk Patients

Atrial fibrillation (AF) is the most common clinical arrhythmia. AF is associated with increased risk for stroke due to blood clots formed in the fibrillating atria. Some patient characteristics increase the likelyhood of AF and at the same time the risk of stroke when AF has developed. To reduce the risk of stroke, anticoagulation therapy is recommended in patients with AF and risk factors (such as high blood pressure, diabetes, vessel disease). However, occasional (paroxysmal) AF may occur without symptoms and remain undetected, leaving patients at risk.

Aim of the prospective randomized study is to compare two management strategies for patients at increased risk for AF but without a known history of AF. Patients are seen regularly (monthly, then quarterly) for follow-up (incl. ECG recording and blood sample). One group of patients additionally receives a subcutaneous implantation of a loop recorder for continuous rhythm monitoring, while the control group remains on standard follow-up. Observation period is one year (optional extension for 3 years). The time to first diagnosis of AF is compared between groups, blood samples are analyzed for potential biomarkers of AF.

Not Provided
Phase 4
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
  • Atrial Fibrillation
  • Hypertension
  • Diabetes
  • Chronic Heart Failure
  • Vascular Disease
Device: Medtronic Reveal XT implantable loop recorder
subcutaneous implantation
  • Experimental: loop recorder
    patients will be implanted with a subcutaneous loop recorder and have regular follow-ups
    Intervention: Device: Medtronic Reveal XT implantable loop recorder
  • No Intervention: regular follow-up
    patients will receive regular follow-ups with standard ECG
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
Active, not recruiting
January 2016
May 2015   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • CHA2DS2-VASc risk score >= 4*
  • 18 years or older

Exclusion Criteria:

  • known history of atrial fibrillation
  • implanted rhythm device
  • pre-existing indication for oral anticoagulation

(*)CHA2DS2-VASc: C - chronic heart failure (1 point); H - hypertension (1 point); A - age >= 75 years (2 points); D - diabetes (1 point); S - stroke (2 points); V - vascular disease (1 point); A - age >=65 and < 75 years (1 point); Sc - sex category (female) (1 point) ;

Sexes Eligible for Study: All
18 Years and older   (Adult, Senior)
Contact information is only displayed when the study is recruiting subjects
Not Provided
Not Provided
Frank R Heinzel, MD, PhD, Medical University of Graz
Medical University of Graz
Not Provided
Medical University of Graz
December 2015

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP