Cardiac pacemaker Cardiac pacemaker The contraction of cardiac muscle (heart muscle) in all animals is initiated by electrical impulses known as action potentials. The rate at which these impulses fire controls the rate of cardiac contraction, that is, the heart rate. The cells that create these rhythmic impulses, setting the pace for blood pumping, are called pacemaker cells, and they directly control the heart rate. They make up the cardiac pacemaker, that is, the natural pacemaker of the heart. In most humans, the concentration of pacemaker cells in the sinoatrial (SA) node is the natural pacemaker, and the resultant rhythm is a
Cardiac contractility modulation which delivers an electrical signal with the intention to result in cardiac contraction, the Cardiac contractility modulation treatment applies the NES, adjusted to and synchronized with the electrical action in the cardiac cycle. In Cardiac contractility modulation therapy, electrical stimulation is applied to the cardiac muscle during the absolute refractory period. In this phase of the cardiac cycle, electrical signals cannot trigger new cardiac muscle contractions, hence this type of stimulation is known as a non-excitatory stimulation. However, the electrical signals increase the influx of calcium ions into the cardiac muscle cells (cardiomyocytes). In contrast to other electrical stimulation treatments