why SA node called pacemaker of heart

Question

anonymous · Answer

The Sinoatrial node is tissue in the heart that generates electrical impulses that cause the heart tissue to contract or the "heart beat" we are all familiar with. This node controls the rhythm of the heart just like an artificial pacemaker does.

anonymous · Answer

sa node has the highest rate of depolarisation than any other areas....so that when it depolarises it spreads the electrical impulse to all parts of heart causing depolarisation of all the areas ......which in turn causes contraction of heart muscle and pulse....other tissues are also having the property of spontaneous depolarisation but sa node has the highest rate or less time interval....so it acts as a pacemaker.....like in a race all racers follow pacemaker