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Sinus Arrhythmia - Everything you Need to Know?

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Many different heart related Health conditions are there, which can affect people. sinus arrhythmia is the most common arrhythmias out of them. sinus arrhythmia happens while breathing and it can be explained as the cyclic change in the heart rate. This disorder is very common around young adults and especially children.

The patients who have been diagnosed with sinus arrhythmia do not show any symptoms of any cardio vascular disorder so there won’t be any effect on the patient’s heart. However, diagnosis of sinus arrhythmia is of utmost importance since it may lead to other complications in the body and is a serious life threating condition.

This article will be discussing the key topics of the what is sinus arrhythmia, what are the symptoms of sinus arrhythmia and how it can be diagnosed, what are the common causes for heart arrhythmias, the risk factor of sinus arrhythmia, how to treat the sinus arrhythmia and the potential complication that are known to occur if sinus arrhythmia is not treated properly.

sinus arrhythmia is the normal increase in heart rate which increase when inspiration. The main reason for sinus arrhythmia to be present in children rather than adults is because there is more accentuated in children.

When the two words in sinus arrhythmia is broken down we see that there are two word which will be useful in understanding about the word more clearly. Sinus refers to the hearts natural pacemaker which is the SA node. It is located in the right atrium. Arrhythmia refers to an irregular rhythm or an abnormal heart rate that will occur due to an irregular electrical impulse or an external stimulant.

The following will cover the key topics that is necessary to better understand what sinus arrhythmia is.

What is Sinus Arrhythmia?

There is a natural wave pattern in the heart beat. In medical notation the heart beat variation is called the PQRST wave form. This wave patter shows how the heart beats. When explaining the notation at the P point the atrial contraction happens. The notation QRS is where the contraction of the ventricles happens.

At the T the relation of the ventricles occurs. So how is this related to sinus arrhythmia? This is related to sinus arrhythmia since you can a wave patter variation of beat to beat in between two P waves in a patient who has been diagnosed by sinus arrhythmia.

When going deep in to the characteristics of sinus arrhythmia we can see that the variation that can be observed in the P to P interval is more than 120ms in a normal healthy person the P to P interval should be less than 120ms. It is also observable that the P to P interval lengthens gradually and there can be sometimes shortening of the P to P interval in a cyclic pattern. This pattern corresponds to the phases of the cycle of respiration when the person is diagnosed with sinus arrhythmia.

However, the morphology of the P wave will be maintained in the shape of a normal sinus P wave without any evidence of any premature contractions of the atrial. The P-R interval will be constant in the person who is diagnosed with sinus arrhythmia so there will be no complication like Mobitz I which is an AV node Block.

In order to cure a disease or human complication the best way is to understand about the mechanism of the complication or disease so that you as a medical practitioner will be treat it correctly. The mechanism of sinus arrhythmia can be broken down into several steps. The complication can be mostly observed in children and young adults who are very healthy and is a very common, normally occurring physiological phenomenon.

However, this phenomenon can occur at any age in both males and females. Many people are afraid of this disease since they think that arrhythmia is a term which is quite often used to show irregular heart conditions like disorganized rhythms of the heart. The main reason for the variation in the heart rhythm is due to the reflex changes during the different steps in the respiratory cycle called vagal tone variations.

The vagal tone is decrease due to the increase in the inspiratory rate. The vagal tone is resorted when the expiration is onset which will lead to a heart rate to be decreased subsequently. The main reason for sinus arrhythmia to be present in children and young adults is that it will decrease with age. This is mainly because as we age there is an age related decrease in the reflex sensitivity of the baroreceptors and in the carotid dispensability.

There is also a special case of sinus arrhythmia which is called “Non-respiratory” sinus arrhythmia, but this condition is less common. The condition is common among elderly patients and is diagnosed mainly because of pathological reasons. The general reason is due to digoxin toxicity or heart diseases. This condition is no linked with the respiratory cycle.

What are the Symptoms of Sinus Arrhythmia and How it Can be Diagnosed?

For a normal healthy person, the heart cycle varies according to the following pattern. It varies while you breathe. The variation of the heart cycle is according to the following pattern where the heart rate increase when you breathe in and goes down when you breathe out. For a person who has sinus arrhythmia the heart cycle can be slightly different when you breathe in and breathe out.

The best way to check it is to check your pulse, where you will feel a slight irregularity while breathing. Rather than that slight change in irregular breathing there are no know symptoms that a person diagnosed with sinus arrhythmia sill show. Some people are even unaware that they have been affected by the medical condition unless they have a serious medical checkup and the healthcare professional point the condition out to them.

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The best way to detect sinus arrhythmia is having an Electrocardiogram or ECG test done. The ECG is known to pick up the electrical activity of the heart. The machine will plot the PARST wave pattern by reading the electrical impulses produced by the heart. Since sinus arrhythmia is associated with the P to P interval it will be quite evident if the patient is suffering from the condition or not.

How the Cardiac Cycle is Produced by Electrical Impulses in the Heart?

Since the condition is a very serious and life threatening situation you will have to watch out for yourself. You can notice the common arrhythmia symptoms can be a good indication that you need to go and consult a doctor. So the medical practitioner will be able to decide whether it is sinus arrhythmia of any other aliment. The most common symptoms for watch out for in general conditions of arrhythmia related problems are:

  • Pain in the Chest
  • Sweating more than usual
  • Fainting or near fainting situations
  • Slowdown of heartbeat. This condition is medically known as bradycardia
  • Increase of heartbeat which is medically known as tachycardia.
  • Shortness in breath
  • A fluttering feeling in your chest
  • Dizziness or lightheadedness at once and not going away.
  • Difficulty in breathing
  • Unresponsiveness, unusual drowsiness and change in alertness
  • Change in mind such as mood swings, disorientations and confusion

The most important fact is when to see a medical professional since the condition will worsen if not treated properly. It is a best practice for you to consult a medical professional if you have any of the above medical conditions. Even if it is not sinus arrhythmia there might be other complications that have caused the symptoms which will lead sever complications than sinus arrhythmia. The medical practitioner will be able to determine the seriousness of the condition and treat you accordingly.

What are the Common Causes for Heart Arrhythmias?

In order to truly understand the reasons behind the sinus arrhythmia we should first know about the how the heart works. Then we should learn about the arrhythmia that will occur in the heart and a few other heart conditions that we mistake for sinus arrhythmia.

The heart is like a pump which supplies blood throughout the body. There are 2 stages for the heart to pump blood. First the atrium is the first part that collect the blood and from all over the body and the blood that is sent to be oxygenated. Then the blood is pushed away from the heart toward the lungs to be oxygenated and to the body for the other purposes by the ventricles in the second step.

The signaling system that provide signals to the heart have small electrical impulses and these are called nodes. They act as automatic pacemakers and keeps the pump working. There are several such nodes that will activate the different chambers in the heart.

The sinoatrial node or the SA node is the first to activate and will produce an electrical impulse that will allow the heart to beat in a proper manner. The SA node above all other nodes s considered as the natural pacemaker which initiates and coordinates the rhythm of the heart. the electrical impulse which is created by the SA node will flow through the walls of the heart and will reach the junction which is the atrioventricular node which also known as the AV node.

The Pacemaker Potential of the SA Node and the AV Node

The electrical impulse on reaching the AV node will cause the heart muscles to contract and therefore both the atria will contract at once. Then it waits for some time and will then contact the ventricles.

This is how the blood is pumped throughout the body. The SA node will produce the electrical impulse about 60 to 80 times a minute. These is a slight gap between two consecutive beats. Now that we have an idea about how the heart functions the idea about heart rhythm disorder should be known in order to understand sinus arrhythmia and what the cause of sinus arrhythmia.

The main cause for many arrhythmias like sinus arrhythmia is the failing or malfunctioning of the hearts electrical system. This is mainly because the normal rhythm of the heart is changed and there is an abnormal rhythm. Many malfunctioning is caused mainly due to the interference of the wiring of the heart the main cause for the wiring to malfunction is the problems that are present in the heart itself.

The other factors like the external environment, what we consume and internal environment can also be causes. The heart muscle also can be irritated when there is a lack of oxygen supply to the heart. The oxygen supply to the heart is inhibited when the lungs are unable to absorb any oxygen form the air we breathe. The other reason for not being able to supply the adequate amount of blood is anemia.

Anemia is most commonly known as the low red blood cell count. In this instance there is less amount of red blood cells that are the main transporters of nutrients and oxygen to the different muscles of the body. When the body has a deficiency of red blood cells the ability to carry oxygen is reduced. Since the heart muscles will not be receiving the adequate mount of oxygen they will be irritated.

The wiring of the heart is also a main cause for rapid heart rates. If there is a short circuit instance in the heart this will lead to increase of the heart rate by even 150 beats per minute instead of the normal 60 to 80 beats. The increase in the heart rate can be cause d by other factors as well.

The abnormal electrolyte levels in the body will be a major contributing factor for the increase in heart rate. Influence from caffeine, over the counter cold medicine, alcohol or stimulants like amphetamines will increase the heart rate which will cause for irregular arrhythmias like sinus arrhythmia.

The slowing down of the heart will also cause irregular heart rhythms which will lead to arrhythmias. If the heart is beating too slowly the body will not be able to maintain the blood flow necessary to do all the activities of the body. This will produce a low blood pressure which will hinder the body abilities which is caused due to the lack of oxygenated and rich blood.

The common cause of respiratory sinus arrhythmia is due to the variation in the vagal tone. The vagal tone is a biological process within our body which is referred to the activity of the vagus nerve. The vagus nerve is originated from the medulla oblongata which is part of the brainstem. Therefore, the vagus nerve becomes a part of the autonomic nervous system which is responsible for the involuntary actions of the body.

The connection that the vagal tone or vagus nerve with respiratory sinus arrhythmia is that there is a natural variation of the heart rate with the respiration and for those who have sinus arrhythmia. The vagus nerve helps regulate the heart rate.

This nerve runs from the chest to the abdomen. The main reason for sinus arrhythmia to be common among children is that there are more variations of the vagal tone in children than in adults. As the children who suffer from sinus arrhythmia grow older the irregularities lessen but it will not be totally cured.

When checking out the main causes for sinus arrhythmia it is evident that the increase and decrease of the heart rate has a major part to play. The most severe case of sinus arrhythmia is called sick sinus syndrome. The reason for sick sinus syndrome is said to be the frequent slow and rapid heart rates which will result in the heart being fatigue. The main cause for the sick sinus syndrome are the causes for atrial flutter and atrial fibrillation.

The Risk Factor of Sinus Arrhythmia


Since many fear the word arrhythmia the condition sinus arrhythmia is feared by man when they get to hear it from the medical practitioner. The main risk factor is that the sinus arrhythmia is occurring in many children and very few adults.

So the parents have to keep a very watchful eye so that they can determine whether their children have sinus arrhythmia or not. The medical condition can also be present in adult as well but there is not much of a probability of it than in children.

Detecting sinus arrhythmia is a very difficult task. This is said because it is one of the most minor arrhythmia to ever show any symptoms. sinus arrhythmia is said to have not symptoms so that the person who has been affected by it will be enjoying life while the sinus arrhythmia worsens. That will be a huge risk considering that there is no way of detecting the condition.

The worst case scenario of sinus arrhythmia is the sick sinus syndrome which is caused by the damaging or the scarring of the hearts electrical system. The risk that is associated with sick sinus syndrome is that it increases with age.

There can be new born who have sick sinus syndrome which is called congenital sick sinus syndrome. Even though the heart can be fixed there will always be a scar for this which will be left and this will provide a path for the appearance of sinus arrhythmia.

sinus arrhythmia is nothing to be afraid of since it is normally present in many individuals but it is best if you can find out more about it by consulting a medical practitioner.

How Can we Treat Sinus Arrhythmia?


There is no special treatment procedure for sinus arrhythmia since it occurs in most individuals. It is considered as a normal variation of the heart rate so it will get back to normal. It is best if you can consult a medical practitioner when they notice that there is a sinus arrhythmia like irregular heart beat in you.

The normal treatment procedures that will be used for normal arrhythmias can be exercise by the medical practitioner on you since sinus arrhythmia is no different.

The Potential Complication that are Known to Occur if Sinus Arrhythmia not Treated Properly


If you do not concern about your sinus arrhythmia this will worsen up and will lead to a disease called sick sinus syndrome. This is somewhat like the worst case scenario of the sinus arrhythmia. Like the sinus arrhythmia this is also cause by the malfunction of the sinus node which acts as the natural pacemaker of the heart.

Sick sinus syndrome is most commonly known as SSS. Since the natural pacemaker is not working properly the SSS can occur since the heart cannot beat properly. There are several types of SSS that you will have to be careful about. The symptoms that are associated with SSS are fatigue, dizziness, chest pain, mental confusion, fainting, disruptive sleep patterns and very slow pulse.

So as a recap of what we did I will sum up about sinus arrhythmia it is evident that it is nothing to be afraid of and it is only noticeable by a medical practitioner during and ECG examination. sinus arrhythmia is the elongation of the interval between the P to P of the wave pattern which is normally less than 120ms.

People will become afraid of sinus arrhythmia since it is associated with the cardiovascular system. Since there are no symptoms of sinus arrhythmia it is very much neglected by many people and it will tend to worsen and cause a medical condition called sick sinus syndrome. The main cause of the sinus arrhythmia like any other arrhythmia is the irregularities in the heart considering the electrical impulse.

There will be internal and external factor that will affect the heart rate such as fatigue, alcohol, caffeine and stimulants. The variation of the vagal tone is the main cause for the sinus arrhythmia and when the variation is returned to normal the sinus arrhythmia will get back to normal. Finally it is seen that the medical condition is most common among children and young adult and can be rarely seen in adults.

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