Sinus arrhythmia ... such rhythms. During an ECG, sticky patches connected to a machine by wires are placed on a person's chest, arms, and legs. The ECG machine then records the heart's electrical ...

Tachycardia-bradycardia syndrome (i.e. pauses after converting to sinus rhythm) Severe sinus ... incompetence (failure of heart rate to increase during exercise) Clinical symptoms depend on ...

But it could also be due to an abnormal heart rhythm ... during vigorous exercise. The heart has a specialized electrical conduction system that starts in a group of cells called the sinus node.

Atrial tachycardia and other ectopic atrial rhythms occur when a site outside of the sinus ... during tachycardic states can lead to decreased cardiac output and symptoms of congestive heart ...