Orthodontic costs vary greatly around the country. An average case fee is about $5000-$6000. Most offices will offer a variety of payment plans. An in house finance with no inâ¦terest typically will only finance the length of treatment with a 20-25% down payment. Average length of treatment is 18-24 months. Making your monthly payment $200-$300.
Under normal conditions, electrical activity is spontaneously generated by the SA node, the physiological pacemaker. This electrical impulse is propagated throughout the right atrium, and through Bachmann's bundle to the left atrium, stimulating the myocardium of the atria to contract. The conduction of the electrical impulse throughout the atria is seen on the ECG as the P wave. As the electrical activity is spreading throughout the atria, it travels via specialized pathways, known as internodal tracts, from the SA node to the AV node.
When the SA node sends out an electrical impulse, the first place it goes is to the AV node. While the SA node sets the rhythm of your pulse, the AV node sets the rhythm of your heart contractions. It delays the signal on its way to the ventricle, giving the atrium time to contract first.It holds it up for about a tenth of a second [source: Signalife ].f the heart can't get enough blood pumping through the body, the body -- and especially the brain -- suffers from lack of oxygen. An artificial pacemaker sends out electrical impulses to mimic the heart's natural pacemaker, the sinoatrial node (SA node), located in the right atrium.