Atrial Fibrillation (AF) importance in stroke

Atrial fibrillation,AF is an under treated heart condition which causes the Atria of heart (two chambers of heart,upper) to quiver ( tremble,shake with slight rapid motion) instead of beating effectively.
          This leads to incomplete out pumping of blood , pooling of blood , in turn clotting.These clots can travel to brain and trigger a major fatal stroke Those with Atrial Fibrillation  are at 5 times more risk of stroke than others.