Page 176 - The Miracle of Electricity in the Body

174 THE MIRACLE OF ELECTRICITY IN THE BODY

The Atrioventricular Node: The Heart’S Spare

Generator
It is exceedingly important that the heartbeat be rhythmical. Defects
of the electrical current in the cells alter the starting time and speed of
the signal. A signal that begins too early will cause the heart to beat pre-
maturely or else cause an insufficient contraction. In the same way, elec-
trical signals that are slowed down or accelerated will result in a delayed
heartbeat, or one that does not take place at all, leading to various heart
disorders.
From that point of view, both the functioning of the heart and its
design must be flawless. Reserve systems in the heart permit this impor-
tant rhythm to be discharged without interruption.
As well as slowing down the electric current and regulating the
heartbeat and pumping blood to the body, the AV node has the vital
function of acting like a reserve generator to replace the main one if any-
thing goes wrong with it. If the SA node is damaged, the AV node takes
over the task of regulating the heartbeat’s rhythm. But this spare gener-

Hypothalamus

SA node

Vagus nerve
Cardiovascular
center
Medulla
AV node
Cardiac nerves

The energy (the action potential) that causes the heart to work is initiated by the
cell group known as the SA node. It spreads as a wave through the atrial muscle,
and reaches the AV node, and from there to the right and left bundle branches. A
special electrical system ensures these processes. By the will of God, this electri-
cal wave fulfills a vital function in our bodies.