Sinus arrhythmia refers to a changing sinus node rate with the respiratory cycle, on inspiration and expiration. This is quite common in young, healthy individuals and has no clinical significance.

Sinus arrhythmia is a variation in the heart's sinus rhythm, usually caused by changes in a person's breathing cycle. It's a common finding, especially in children and young adults, and its ...

The first ECG strip below shows a P wave with sinus morphology, thus normal sinus rhythm. If the P wave has a morphology different from the typical sinus morphology, it is termed ectopic ...