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The effect of antithyroid treatment on atrial conduction times in patients with subclinical hyperthyroidism

Alper Buğra Nacar1, Gürkan Acar, Hikmet Yorgun

  • 1Elbistan State Hospital, Kahramanmaraş, Turkey. dralpernacar@hotmail.com

Echocardiography (Mount Kisco, N.Y.)
|May 30, 2012
PubMed

Insights

Subclinical hyperthyroidism (SH) prolongs atrial conduction time, increasing atrial fibrillation risk. Antithyroid treatment normalized conduction times, suggesting a preventive role against atrial fibrillation.

Area of Science:

  • Cardiology
  • Endocrinology
  • Medical Imaging

Background:

  • Prolonged atrial conduction time is linked to increased atrial fibrillation risk.
  • Subclinical hyperthyroidism (SH) may affect atrial electrophysiology.
  • Tissue Doppler imaging (TDI) measures atrial conduction time.

Purpose of the Study:

  • To assess the impact of SH on atrial conduction time.
  • To evaluate the effect of antithyroid treatment on atrial conduction in SH patients.

Main Methods:

  • 30 SH patients and 30 controls underwent TDI measurements of atrial conduction.
  • Intra- and interatrial conduction delays were calculated.
  • Measurements were taken at baseline and after achieving euthyroid state with propylthiouracil.

Main Results:

  • SH patients exhibited significantly prolonged atrial conduction times compared to controls.
  • Interatrial, right, and left intraatrial electromechanical delays were longer in SH patients.
  • Antithyroid treatment normalized these delays, bringing them closer to control values.

Conclusions:

  • Subclinical hyperthyroidism is associated with prolonged atrial conduction.
  • Normalization of conduction times after treatment suggests a potential mechanism for preventing atrial fibrillation in SH patients.
Abstract

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