EKG Chapter 5 Rhythm Part I

Arrhythmia is is used to denote any abnormal rhythm. So dysrhythmia (bad rhythm) has the same meaning.

The SA Node, also known as the sinoatrial node, is responsible for generating pacing impulses in the heart. These impulses are produced at a constant, unvarying rate, resulting in cycles of equal length. As a result, the rhythm of the heart is described as regular.

The correct answer is the right atrium - the anterior, the middle, and the posterior. The atrial conduction system refers to the network of specialized cells that initiate and coordinate the electrical signals in the atria of the heart. These signals are responsible for the contraction of the atria and the proper functioning of the heart. The three specialized internodal tracts mentioned are located in the right atrium and are responsible for conducting the electrical signals from the sinoatrial (SA) node to the atrioventricular (AV) node.

Depolarization of the atrial myocardium refers to the electrical activation of the atria, which causes them to contract. This depolarization is represented on an electrocardiogram (ECG) as the P wave. Therefore, the correct answer is P wave.

During inspiration, sympathetic stimulation of the SA node occurs, leading to an increase in heart rate. This is because the sympathetic nervous system activates the release of norepinephrine, which increases the firing rate of the SA node and enhances the conduction of electrical impulses in the heart. On the other hand, during expiration, parasympathetic inhibition of the SA node takes place. The parasympathetic nervous system releases acetylcholine, which slows down the firing rate of the SA node and reduces the conduction of electrical impulses in the heart. Therefore, the slight increase in heart rate is due to sympathetic stimulation, while the slight decrease in pacing rate is due to parasympathetic inhibition.

Sinus arrhythmia is a normal, but extremely minimal, increase in heart rate during inspiration and an extremely minimal decrease in heart rate during expiration. This is due to the natural variation in the autonomic nervous system's control over the heart rate. During inspiration, there is increased activity in the sympathetic nervous system, leading to a slight increase in heart rate. During expiration, there is increased activity in the parasympathetic nervous system, leading to a slight decrease in heart rate. Sinus arrhythmia is a benign condition and does not cause any symptoms or require treatment.

Bachman's bundle is a specialized pathway that originates in the SA Node, which is known as the natural pacemaker of the heart. It is responsible for initiating the electrical impulses that regulate the heart's rhythm. The bundle then distributes these depolarization signals to the atrium, the upper chambers of the heart. This allows for coordinated contraction and efficient pumping of blood into the ventricles, the lower chambers of the heart. Therefore, the correct answer is Atrium.

The SA Node is responsible for generating regular pacing impulses that depolarize the atria. These impulses occur at a rate of 60 to 100 per minute.

The SA Node generates a regular electrical signal called the Sinus Rhythm that paces the heart. Each pacemaker impulse from the SA Node spreads through both atria as an advancing wave of depolarization.