Less commonly, sinus arrhythmia may indicate an underlying medical problem, like heart disease or heart block. The heart's normal sinus rhythm is created by electrical signals that spread ...

Sinus rhythm (a.k.a. normal sinus rhythm) refers to the normal heart beat originating from the sinoatrial node. This is manifested as an upright P wave in lead II of the ECG. Sinus bradycardia ...

6,11 Heart rates ≥30 beats/min are considered normal in highly trained athletes. Sinus arrhythmia is also common, particularly in younger athletes. IRBBB (commonly characterised as an rSR′ pattern in ...