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Trial record 1 of 1 for:    NCT01945229
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Thumb-ECG Ambulant Screening for Atrial Fibrillation in Patients Treated for Hyperthyroidism (TAMBOURINE) (TAMBOURINE)

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. Identifier: NCT01945229
Recruitment Status : Terminated (Preliminary analyses of data indicated study should be terminated for futility)
First Posted : September 18, 2013
Last Update Posted : September 4, 2020
Information provided by (Responsible Party):
Peter Giesecke, M.D, Karolinska Institutet

Brief Summary:

Background: Atrial fibrillation is a common heart rhythm disturbance affecting some 1-2% of the western population. It may cause symptoms such as irregular heartbeats, shortness of breath, and fatigue. It may also be asymptomatic (ie "silent atrial fibrillation). In some cases, atrial fibrillation is permanent whereas in others it is sporadic. Regardless of symptoms, there is an increased risk of stroke in some patients with this condition. Novel technologies are being developed to increase detection of silent atrial fibrillation, in order to find patients who might benefit from treatment with oral anticoagulants (blood-thinning medications) in order to reduce the risk of stroke. One of these technologies is thumb-ECG, a simple way for a patient to have his or her heart rhythm reliably analyzed at home.

Hyperthyroidism (sometimes referred to as "toxic goiter") is defined as an excessive production of thyroid hormone. It is known that hyperthyroidism may cause atrial fibrillation in about 8% of cases.

Objective: To provide thumb-ECG-monitors to hyperthyroid patients before and after treating their hormonal disturbance, in order to find episodes of silent atrial fibrillation.

Design: Prospective observational study.


  • Primary hypothesis: Silent atrial fibrillation is at least as common as overt atrial fibrillation in hyperthyroid patients.
  • Secondary hypothesis nr 1: Atrial fibrillation continues to be more prevalent compared to the normal population even after hyperthyroidism is treated.
  • Secondary hypothesis nr 2: The majority of patients with hyperthyroidism and atrial fibrillation are at increased risk of stroke and should be considered for treatment with oral anticoagulants.

Condition or disease
Hyperthyroidism Atrial Fibrillation

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Study Type : Observational
Actual Enrollment : 110 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Thumb-ECG Ambulant Screening for Atrial Fibrillation in Patients Treated for Hyperthyroidism (TAMBOURINE)
Study Start Date : February 2014
Actual Primary Completion Date : August 2020
Actual Study Completion Date : August 2020

Resource links provided by the National Library of Medicine

Hyperthyroid patients
Patients with hyperthyroidism admitted for treatment with radioiodine or antithyroid drugs

Primary Outcome Measures :
  1. Prevalence of asymptomatic (silent) atrial fibrillation in hyperthyroid patients [ Time Frame: Upon inclusion and 2 weeks onwards ]
    Upon inclusion, each patient will receive a thumb-ECG-monitor to take home. He/she will register his/her heart rhythm twice daily, and can also register at will upon symptoms. This will continue for 2 weeks, after which the monitor is returned.

Secondary Outcome Measures :
  1. Prevalence of asymptomatic (silent) atrial fibrillation in patients treated for hyperthyroidism. [ Time Frame: Between 12 and 14 weeks after inclusion ]
    When a patient comes back to the policlinic after hyperthyroidism treatment (typically 3 months later), the same procedure is performed as upon inclusion. Thumb-ECG-monitoring is performed during a 2-week period.

  2. Prevalence of risk factors for stroke in patients with atrial fibrillation [ Time Frame: Momentary (day 1, upon inclusion) ]
    Risk factors for stroke in atrial fibrillation according to the CHADS-VASc-scoring system.

Information from the National Library of Medicine

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Ages Eligible for Study:   Child, Adult, Older Adult
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
We will screen all patients residing in the extended region around Stockholm, Sweden who have been referred and admitted to the Radiumhemmet clinic for investigation (and usually treatment) with radioiodine. As of February 2016, we will also include patients referred for treatment with antithyroid drugs at the endocrinology clinics of 1) Sahlgrenska University Hospital, Gothemburg Sweden, 2) Karolinska University Hospital, Stockholm, Sweden, 3) Danderyds Hospital, Stockholm, Sweden

Inclusion Criteria:

  • Patient is deemed suitable for treatment with radioiodine or antithyroid drugs
  • Patient has a thyreotropin (TSH) value below 0,1 mIU/L, measured less than 2 weeks before inclusion
  • Patient has a CHADS-VASc-score of 1 point or higher (excluding if 1 point is for female sex only)
  • Patient gives written consent to participate in study

Exclusion Criteria:

  • Patient has a previously known diagnosis of atrial fibrillation

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 identifier (NCT number): NCT01945229

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Medicine Clinic, Sahlgrenska University Hospital
Gothemburg, Sweden, 41345
Endocrinology Clinik, Karolinska University Hospital
Stockholm, Sweden, 17176
Medicine Clinic, Danderyds Hospital
Stockholm, Sweden, 18288
Sponsors and Collaborators
Karolinska Institutet
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Study Chair: Mårten Rosenqvist, Prof Karolinska Institutet
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Responsible Party: Peter Giesecke, M.D, M.D., specialist internal medicine and cardiology, Karolinska Institutet Identifier: NCT01945229    
Other Study ID Numbers: 3/9 B
First Posted: September 18, 2013    Key Record Dates
Last Update Posted: September 4, 2020
Last Verified: September 2020
Additional relevant MeSH terms:
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Atrial Fibrillation
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes
Thyroid Diseases
Endocrine System Diseases