Thumb-ECG Ambulant Screening for Atrial Fibrillation in Patients Treated for Hyperthyroidism (TAMBOURINE)

NCT01945229 | Terminated

• 1 other identifier: 3/9 B
• Study Type: observational
• Target: 110
• Locations: 1 country
• Sites: 3

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. Hypotheses:

• 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.

Conditions

Hyperthyroidism; Atrial Fibrillation

Outcome Measures

Primary Outcomes (1)

• Prevalence of asymptomatic (silent) atrial fibrillation in hyperthyroid patients

  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.

  Upon inclusion and 2 weeks onwards

Secondary Outcomes (2)

• Prevalence of asymptomatic (silent) atrial fibrillation in patients treated for hyperthyroidism.

  Between 12 and 14 weeks after inclusion

• Prevalence of risk factors for stroke in patients with atrial fibrillation

  Momentary (day 1, upon inclusion)

Study Arms (1)

Hyperthyroid patients

Patients with hyperthyroidism admitted for treatment with radioiodine or antithyroid drugs

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• 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

You may qualify if:

• Patient is deemed suitable for treatment with radioiodine or antithyroid drugs
• 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

You may not qualify if:

• Patient has a previously known diagnosis of atrial fibrillation

Sponsors & Collaborators

• Karolinska Institutet: lead

Study Sites (3)

Medicine Clinic, Sahlgrenska University Hospital

Gothemburg, 41345, Sweden

Location

Endocrinology Clinik, Karolinska University Hospital

Stockholm, 17176, Sweden

Location

Medicine Clinic, Danderyds Hospital

Stockholm, 18288, Sweden

Location

Related Publications (4)

• Frost L, Vestergaard P, Mosekilde L. Hyperthyroidism and risk of atrial fibrillation or flutter: a population-based study. Arch Intern Med. 2004 Aug 9-23;164(15):1675-8. doi: 10.1001/archinte.164.15.1675.

  PMID: 15302638 BACKGROUND

• Osman F, Franklyn JA, Holder RL, Sheppard MC, Gammage MD. Cardiovascular manifestations of hyperthyroidism before and after antithyroid therapy: a matched case-control study. J Am Coll Cardiol. 2007 Jan 2;49(1):71-81. doi: 10.1016/j.jacc.2006.08.042. Epub 2006 Dec 13.

  PMID: 17207725 BACKGROUND

• Metso S, Auvinen A, Salmi J, Huhtala H, Jaatinen P. Increased long-term cardiovascular morbidity among patients treated with radioactive iodine for hyperthyroidism. Clin Endocrinol (Oxf). 2008 Mar;68(3):450-7. doi: 10.1111/j.1365-2265.2007.03064.x. Epub 2007 Oct 17.

  PMID: 17941909 BACKGROUND

• Camm AJ, Lip GY, De Caterina R, Savelieva I, Atar D, Hohnloser SH, Hindricks G, Kirchhof P; ESC Committee for Practice Guidelines (CPG). 2012 focused update of the ESC Guidelines for the management of atrial fibrillation: an update of the 2010 ESC Guidelines for the management of atrial fibrillation. Developed with the special contribution of the European Heart Rhythm Association. Eur Heart J. 2012 Nov;33(21):2719-47. doi: 10.1093/eurheartj/ehs253. Epub 2012 Aug 24. No abstract available.

  PMID: 22922413 BACKGROUND

MeSH Terms

Conditions

Hyperthyroidism; Atrial Fibrillation

Condition Hierarchy (Ancestors)

Thyroid Diseases; Endocrine System Diseases; Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Mårten Rosenqvist, Prof

  Karolinska Institutet

  STUDY CHAIR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: M.D., specialist internal medicine and cardiology

Study Record Dates

• First Submitted: September 13, 2013
• First Posted: September 18, 2013
• Study Start: February 1, 2014
• Primary Completion: August 1, 2020
• Study Completion: August 1, 2020
• Last Updated: September 4, 2020

Record last verified: 2020-09

Locations

SE (3)