Which arrhythmia is commonly associated with sudden death?

Ventricular fibrillation is a critical arrhythmia often associated with sudden death. This condition occurs when the electrical activity in the ventricles becomes chaotic, leading to ineffective contractions and the inability of the heart to pump blood effectively. As a result, it can cause an immediate loss of consciousness and, if not treated promptly, can lead to death within minutes.

The lethality of ventricular fibrillation is primarily due to its rapid onset and the fact that it disrupts normal heart rhythm to such an extent that the heart is unable to maintain adequate blood flow to vital organs. Immediate intervention, typically with defibrillation, is required to restore a normal rhythm and prevent irreversible damage or death.

The other arrhythmias listed, while they can carry risks of complications or may lead to sudden death in certain circumstances, are not as universally recognized as being critically life-threatening in the acute setting as ventricular fibrillation. For instance, atrial fibrillation can lead to stroke and other complications but is less likely to result in sudden death on its own compared to ventricular fibrillation. Ventricular tachycardia can be life-threatening, especially if it degenerates into ventricular fibrillation, but it may occasionally be stable and not immediately life-threatening. Supraventricular