Cardiac Rhythm — Trending

A normal rhythm, known as , starts in the sinoatrial (SA) node—the heart's natural pacemaker. This signal travels through the heart in a specific sequence, which is visualized on an electrocardiogram (ECG) as the PQRST wave pattern:

Your heart rhythm naturally fluctuates based on activity, stress, or sleep. However, it is considered abnormal (an arrhythmia) when it is inappropriately fast, slow, or irregular. : A fast resting heart rate exceeding 100 bpm. Bradycardia : A slow resting heart rate below 60 bpm. cardiac rhythm

: A common, harmless variation where the heart rate slightly increases during inhalation and decreases during exhalation. A normal rhythm, known as , starts in