Which term describes chaotic electrical activity in the atria resulting in ineffective contractions?

• A. Aneurysm
• B. S1S2
• C. A fib
• D. AAA

Answer: (C)

Chaotic electrical activity in the atria with ineffective contractions is atrial fibrillation. In AF, multiple foci generate rapid, disorganized impulses that cause the atria to quiver rather than contract as a coordinated unit. This loss of effective atrial contraction reduces atrial kick, can lead to irregular, often rapid ventricular rates, and increases the risk of blood clots forming in the atria with potential embolic stroke. The other terms don’t describe this rhythm disturbance: an aneurysm is a dilation of a vessel or heart chamber, S1S2 refers to heart sounds, and an abdominal aortic aneurysm is a dilation of the abdominal aorta.