Tachycardia-bradycardia syndrome (i.e. pauses after converting to sinus rhythm) Severe sinus bradycardia Sinus pauses/sinus arrest Sinoatrial nodal exit block Chronotropic incompetence (failure of ...

The rhythm is either sinus rhythm or not sinus rhythm. Sinus rhythm refers to the origination of the electrical activity coming from the sinus node — also known as the sinoatrial node ...

With a sustained block of the SNS, the researchers observed loss of the day-night rhythm in sinus node pacemaking and in pacemaking ion channels. Surprisingly, the heart’s local circadian clock ...