It depdends: There are many causes of toe spasms/cramps and it is important to identify the source. Cramps and spasms can be due to dehydration and low potassium. But they can also be due to a nerve conditions as well. I recommend you see a specialist for further evaluation. ...Read more.
1 The SA node (called the pacemaker of the heart) sends out an electrical impulse. 2  The upper heart chambers (atria) contract. 3  The AV node sends an impulse into the ventricles.  The lower heart chambers (ventricles) contract or pump.
The Conduction System. Electrical impulses from your heart muscle (the myocardium) cause your heart to beat (contract). This electrical signal begins in the sinoatrial (SA) node, located at the top of the right atrium. When an electrical impulse is released from this natural pacemaker, it causes the atria to contract.