What defines an arrhythmia?

An arrhythmia is defined as an abnormal heart rhythm. This means that the heart may beat too fast, too slow, or in an irregular pattern compared to the normal rhythm, which can be assessed through various monitoring methods. Understanding arrhythmias is crucial because they can indicate underlying health issues or can lead to complications such as stroke or heart failure if not properly managed.

The other options do not accurately encompass the definition of arrhythmia. A decrease in heart rate might describe bradycardia, while an unusual heart sound could refer to a murmur or other cardiac anomalies, and an increase in blood pressure pertains to hypertension. None of these terms directly address the concept of rhythm disturbances in the heart.