The reason why sinoatrial node can be the normal starting point of heart

The main reasons why sinoatrial node can become the normal cardiac pacing point are as follows: sinoatrial node has autonomy, conductivity, excitability and blood supply, which work together to effectively control cardiac rhythm and maintain normal cardiac function. Sinus node cells can automatically excite at a certain frequency, which is the most important reason why sinus node becomes the normal starting point of heart. 2. Conductivity of sinus node: Excitation of sinus node can be transmitted to the whole heart through atrial muscle, which makes excitation of sinus node effectively control the rhythm of heart. 3. Excitability of sinus node: Sinus node excitability is high, even in other parts of the heart excited, sinus node can also give priority to excitation and control the rhythm of the heart.4. sinus node blood supply: sinus node has an abundant blood supply, which ensures the normal function and metabolism of sinus node cells, so that it can continue to emit excitation. To sum up, the reason why sinoatrial node can become the normal starting point of heart is that it has the advantages of autonomy, conductivity, excitability and blood supply. These factors work together to make sinoatrial node effectively control the rhythm of heart and maintain normal function of heart.