Which arrhythmia is characterized by a rapid and irregular heart rhythm?

Atrial fibrillation is characterized by a rapid and irregular heart rhythm due to chaotic electrical activity in the atria. Unlike in normal sinus rhythm, where the heart beats in a coordinated manner, atrial fibrillation leads to ineffective atrial contractions, resulting in irregularly timed ventricular contractions. This irregularity is what makes the heart rhythm rapid and erratic.

In patients with atrial fibrillation, the absence of organized atrial activity can cause the heart rate to vary widely, often exceeding 100 beats per minute. This condition can lead to symptoms such as palpitations, shortness of breath, and an increased risk of stroke due to the formation of blood clots in the atria.

Understanding atrial fibrillation is crucial for paramedics and healthcare providers, as it requires prompt assessment and management to minimize complications and stabilize the patient. The other arrhythmias mentioned do not share the same characteristics of rapid and irregular rhythm; for instance, bradycardia is characterized by a slow heart rate, while ventricular tachycardia has a rapid, but usually more regular, rhythm. Asystole represents a complete absence of ventricular electrical activity, resulting in no heart contractions.