Atrial fibrillation primarily affects what part of the heart's function?

Atrial fibrillation primarily disrupts the atrial contraction rhythm. In a normal heart, the atria contract in a coordinated manner to push blood into the ventricles. However, in atrial fibrillation, the electrical signals in the atria become disorganized, leading to rapid and irregular contractions that can significantly alter how effectively the atria empty blood into the ventricles. This irregularity contributes to a decrease in overall cardiac efficiency and increases the risk of clot formation due to stagnant blood in the atria.

While the condition may also impact the heart’s overall rate and potentially affect ventricular contractions over time, the most significant and direct effect is on the rhythm of atrial contractions. Therefore, understanding atrial fibrillation involves recognizing its primary impact on the atrial function.