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.
All the while being in sync with the pacemaker cells; this is the property that allows the pacemaker cells to control contraction in all other cardiomyocytes. Cells in the SA node spontaneously depolarize, ultimately resulting in contraction, approximately 100 times per minute.hese cells form the atrioventricular node (or AV node), which is an area between the left atrium and the right ventricle within the atrial septum, will take over the pacemaker responsibility. The cells of the AV node normally discharge at about 40-60 beats per minute, and are called the secondary pacemaker.