Atrial Fibrillation

Introduction

Atrial fibrillation is the most widespread disorder of the heart rhythm as observed by doctors. It is a great issue in the public health with respect to not only the number of people who are affected by this disease, but also because the cost of treatment for this disorder is very high. According to statistics, over 22 million people in the United States have atrial fibrillation and more than 15 to 20 percent of the strokes occur as a result of this disorder (www.nhlbi.nih.gov).

Anatomy of Heart

An electrical signal stretches out the bottom of the heart from its top, with every heart beat. As these electrical signal moves, it makes the heart pump blood by contractions. Every electrical signal starts in the sinoatrial (SA) or sinus node, which is a group of cells in the heart. This node is situated in the right atrium. When a healthy adult heart is at rest, the SA node launches an electrical signal to initiate a new heart beat ranging from 60 to 100 times in a time period of one minute, this rate of heart may not be the same in athletes who are completely fit. This electrical signal moves across the left and right atria from the SA node, which in turn contracts the atria, pumping out blood into the ventricles

After this, the electrical signal travels downwards to atrioventricular (AV) node which is also a group of cells situated in between the ventricles and the atria. At this position, the signal becomes slightly dawdling, in order to allow time for the ventricles to fill with blood completely. Consequently, the electrical signal then moves towards the ventricles, which in turn allows pumping of blood to the lungs and to the entire body through the ventricles. Then the ventricles get to rest, meanwhile the process of a new heartbeat starts all again in the SA. In this rhythmic disorder of heart, electrical signals do not starts in the SA node; rather, they instigate either near the pulmonary veins or another part of atria (www.cardiosmart.org).

Thus, these signals remain unsuccessful in travelling throughout the heart normally. As a result, the signals may spread all over the atria in a disorganized and quick manner, as a consequence of which the atria may fibrillate. The abnormal signals fill the AV node with electrical signals which makes the ventricles to beat very fast. Nevertheless, the AV node ...