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Graz Study on the Risk of Atrial Fibrillation (GRAF)

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ClinicalTrials.gov Identifier: NCT01461434
Recruitment Status : Unknown
Verified December 2015 by Frank R Heinzel, MD, PhD, Medical University of Graz.
Recruitment status was:  Active, not recruiting
First Posted : October 28, 2011
Last Update Posted : December 22, 2015
Information provided by (Responsible Party):

Study Description
Brief Summary:

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.

Condition or disease Intervention/treatment Phase
Atrial Fibrillation Hypertension Diabetes Chronic Heart Failure Vascular Disease Device: Medtronic Reveal XT implantable loop recorder Phase 4

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 82 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Official Title: Randomized Controlled Trial to Evaluate Implanted Event Recorders for the First Diagnosis of Atrial Fibrillation in High-risk Patients
Study Start Date : November 2011
Primary Completion Date : May 2015
Estimated Study Completion Date : January 2016

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Experimental: loop recorder
patients will be implanted with a subcutaneous loop recorder and have regular follow-ups
Device: Medtronic Reveal XT implantable loop recorder
subcutaneous implantation
No Intervention: regular follow-up
patients will receive regular follow-ups with standard ECG

Outcome Measures

Primary Outcome Measures :
  1. Time to first diagnosis of atrial fibrillation [ Time Frame: 12 months ]

Secondary Outcome Measures :
  1. 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 ]
  2. Hospitalizations [ Time Frame: 12 months ]
  3. 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 ]
  4. Death [ Time Frame: 12 months ]
  5. Stroke [ Time Frame: 12 months ]

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

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) ;

Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01461434

LKH/Uniklinikum - Klinische Abteilung für Kardiologie
Graz, Austria, 8036
Sponsors and Collaborators
Medical University of Graz
More Information

Responsible Party: Frank R Heinzel, MD, PhD, Associate Professor Frank R. Heinzel, MD, PhD, Medical University of Graz
ClinicalTrials.gov Identifier: NCT01461434     History of Changes
Other Study ID Numbers: GRAF-01-SCCT
First Posted: October 28, 2011    Key Record Dates
Last Update Posted: December 22, 2015
Last Verified: December 2015

Keywords provided by Frank R Heinzel, MD, PhD, Medical University of Graz:
atrial fibrillation
stroke prevention
implantable loop recorder

Additional relevant MeSH terms:
Heart Failure
Atrial Fibrillation
Vascular Diseases
Heart Diseases
Cardiovascular Diseases
Arrhythmias, Cardiac
Pathologic Processes