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.
Smooth muscle and cardiac muscle are both involuntary muscles. Specialized cardiac muscle fibers make up the pacemaker that regulates your heart rate. This pacemaker, in turn, is under the control of the autonomic nervous system, the part of the nervous system that operates below your level of consciousness.