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

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational

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

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 hyperthyr

    Detailed Summary:
    Sponsor: Karolinska Institutet

    Current Primary Outcome: 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.


    Original Primary Outcome: Same as current

    Current Secondary Outcome:

    • 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.
    • 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.


    Original Secondary Outcome: Same as current

    Information By: Karolinska Institutet

    Dates:
    Date Received: September 13, 2013
    Date Started: February 2014
    Date Completion: December 2018
    Last Updated: August 29, 2016
    Last Verified: August 2016