The ECG criteria to diagnose sinus arrhythmia is a variation of the P-P interval, from one beat to the next, of at least 0.12 seconds, or 120 milliseconds. Sinus arrhythmia ― if not in a young ...

Sinus arrhythmia is a variation in the heart's sinus rhythm, usually caused by changes in a person's breathing cycle. It's a ...

1 The majority of disorders associated with increased risk of sudden cardiac death (SCD), such as cardiomyopathies and primary electrical diseases, are suggested by abnormal findings present on an ECG ...

This results in an upright P wave in lead II on the ECG. If there is a P wave before every QRS complex, and it has a sinus morphology, then normal sinus rhythm, or NSR, is said to be present.

In fact, up to 60% of athletes demonstrate ECG changes (in isolation or in combination) such as sinus bradycardia, sinus arrhythmia, first-degree atrioventricular (AV) block, early repolarisation, ...