Which arrhythmia is most associated with Graves' disease?

Atrial fibrillation is the arrhythmia most commonly associated with Graves' disease due to the hyperthyroid state induced by the condition. Graves' disease leads to increased thyroid hormone production, which can result in various cardiac manifestations, primarily through increasing the heart rate and affecting the electrical conduction system of the heart.

In patients with hyperthyroidism, there is an increased heart rate and increased cardiac output, which elevate the risk of developing atrial fibrillation. The rapid and irregular heartbeat seen in atrial fibrillation can lead to symptoms such as palpitations, fatigue, and increased risk of stroke. The presence of elevated levels of thyroid hormones can also contribute to structural changes in the heart, promoting the development of this specific arrhythmia.

Other arrhythmias listed, such as ventricular fibrillation and premature ventricular contractions, are less commonly linked to Graves' disease specifically. Atrial flutter may occur but is not as strongly associated with the condition as atrial fibrillation. This makes atrial fibrillation the most recognized and significant arrhythmia associated with Graves’ disease in clinical practice.