Rapid conduction of sinus node excitation to the atrioventricular junction relies on the conduction of the common atrial muscle and the interjunctional bundle. The sinus node is the normal pacing point of the heart and sends out pulses at a certain frequency every minute. The signals travel down the conduction system in the heart to the atrioventricular (AV) junction area, and the main conduction tissues are the common atrial muscle and the interjunctional bundles. The main conduction tissues are the common atrial muscle and the interjunctional bundles. There is a fixed conduction system in the heart, under which the atria and ventricles contract in a sequential manner to fulfill the normal ejection function of the heart. The function of the conduction system of the heart is affected by many factors, such as the level of ions, blood supply to the heart, etc. Electrolyte changes and myocardial ischemia can lead to abnormal conduction signals and affect the normal beating of the heart. If you notice abnormal heartbeat rhythm or frequent symptoms of palpitations, please seek medical attention to avoid delay.