Which term describes a heart condition where blood is not pumped effectively due to quivering muscle?

The term that accurately describes a heart condition where blood is not pumped effectively due to quivering muscle is fibrillation. In this condition, the heart's muscles, particularly in the atria or ventricles, exhibit rapid and chaotic electrical activity, leading to ineffective contraction. This quivering results in the heart's inability to pump sufficient blood, potentially causing symptoms such as palpitations, dizziness, or even loss of consciousness.

Fibrillation can occur in two main forms: atrial fibrillation and ventricular fibrillation. Atrial fibrillation involves the upper chambers of the heart (atria) and is characterized by an irregular and often rapid heart rate. Ventricular fibrillation affects the lower chambers (ventricles) and is a medical emergency requiring immediate attention to restore effective heart function.

Understanding the mechanics of fibrillation highlights why it leads to ineffective blood pumping. The disorganized electrical signals cause the heart muscle to contract ineffectively, preventing coordinated blood flow.

The other terms refer to different heart-related conditions. Heart block involves interruptions in the electrical signals controlling the heartbeat, which can lead to slower heart rates but doesn't necessarily involve muscle quivering. An aneurysm pertains to an abnormal bulging of a blood vessel wall, which isn't a condition characterized by