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[Atrial fibrillation and thyroid gland]

Massimo Bindi1, Massimiliano Pinelli, Javier Rosada

  • 1IV Divisione Medica, Azienda Ospedaliera Pisana, Pisa. bindi@ao-pisa.toscana.it

Recenti Progressi in Medicina
|February 28, 2006
PubMed

Insights

Thyroid dysfunction is linked to atrial fibrillation, even with normal thyroid function tests. This study suggests thyroid hormone level checks and ultrasounds for atrial fibrillation patients to detect underlying thyroid issues.

Area of Science:

  • Cardiology
  • Endocrinology
  • Thyroidology

Background:

  • Thyroid dysfunction is a known cause of atrial fibrillation.
  • The prevalence of atrial fibrillation is similar in subclinical and overt hyperthyroidism.
  • Hypothyroidism and Low-T3 syndrome are also associated with atrial fibrillation and cardiac risk.

Purpose of the Study:

  • To investigate the prevalence of thyroid dysfunction and thyroid abnormalities in patients with atrial fibrillation.
  • To assess the relationship between thyroid function and atrial fibrillation.
  • To determine the utility of thyroid hormone testing and ultrasound in atrial fibrillation management.

Main Methods:

  • Studied thyroid function and performed thyroid ultrasound in 100 patients with atrial fibrillation.
  • Assessed thyroid hormone levels (including T3).
  • Evaluated thyroid gland structure via ultrasound, noting nodules and size.

Main Results:

  • Only 10 out of 100 patients (10%) had abnormal thyroid function.
  • 30 patients (30%) presented with Low-T3 syndrome.
  • 66 patients (66%) had thyroid nodules, with 38 measuring 10 mm or larger.

Conclusions:

  • Thyroid dysfunction is present in a significant portion of atrial fibrillation patients, including those with Low-T3 syndrome.
  • Thyroid nodules are common in atrial fibrillation patients.
  • Recommend thyroid hormone level assessment and thyroid ultrasound in atrial fibrillation patients, even with normal initial thyroid function tests.

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