What heart rate is typically associated with atrial fibrillation?

What heart rate is typically associated with atrial fibrillation?

• A. 60-100 bpm
• B. 250-350 bpm
• C. 350-450 bpm
• D. 450-600 bpm

Answer: (C)

Atrial fibrillation is characterized by a rapid and irregular heartbeat that generally does not follow a predictable pattern. The heart rate during atrial fibrillation can vary widely, but it is commonly noted that the ventricular response can be quite fast, often exceeding 100 beats per minute. While a lot of patients may experience a heart rate of 100-175 bpm during atrial fibrillation, various factors, such as the condition's duration and the patient's overall health, can influence this rate.

With respect to the numbers provided, the highest ranges (350-450 bpm and upwards) represent possible atrial rates but are typically not sustainable as effective heart rhythms for the ventricles. In practical terms, most individuals with atrial fibrillation will not sustain ventricular rates as high as those in upper options because they would likely experience significant hemodynamic compromise and fatigue.

The average range that reflects typical atrial activity is much more aligned with lower values, as the rapid, chaotic activity in the atria leads to this increased rate, ultimately causing the ventricles to respond erratically. A common misconception is that very high rates characterize atrial fibrillation exclusively, but while it might reach such elevations in extreme cases, it's more accurately seen within the moderate rates typically observed.