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 ...

Furthermore, the proportion of time in sinus rhythm whilst on assigned antiarrhythmia therapy did not effect these outcomes in the 1,316 patients for whom electrocardiograms were available.