Sinus Arrhythmia – a not so common term. Most people will probably know either of the two words; taken together, the meaning could be lost. To explain it very briefly, it is a medical term that describes the condition of the heartbeat. Or, to be more precise, it describes the condition that the heartbeat is out of rhythm. Arrhythmia occurs when that steady rhythm goes out of place; when the heart skips a beat. But should this be a cause for concern? Let’s find out in the words that follow.
The Body’s Music
The human body is an excellently built, well-oiled machine maintained by a natural organization and system. In this light, a human body is comparable to an orchestra or ensemble – an orderly unit made up of diverse smaller groups that produce different notes from one another; but when put together, harmonize into a single complex piece of music.
If the human body is an orchestra, then the heart is most analogous to the drum; the giver of beats, the keeper of speed or tempo. The heart’s rhythm dictates all the other organs’ pace. The heart’s rhythm sets the mood. But what happens when the measured beats of the body’s drum go awry? In music, it is known as syncopation; in medical terms, it is called arrhythmia – without rhythm.
Sinus Arrhythmia, or Respiratory Sinus Arrhythmia or RSA for short, is a normal phenomenon where the heart rate changes its pace in tune with the breath cycle. More accurately, the heart rate slightly speeds up when breathing in and slightly slows down when breathing out. This variation is very subtle and may not be noticeable even when taking a pulse manually, but it can be seen using medical diagnostic tools like electrocardiograms.
The term “sinus” refers to the heart’s own “pacemaker” tissue, the sinoatrial or SA node, and “arrhythmia” means “without rhythm”. But although the name contains the phrase “without rhythm”, sinus arrhythmia should not be confused with other cardiac arrhythmias which are dangerous and which could be life-threatening, as in the case of atrial or ventricular fibrillation, atrial flutter, heart blocks, and the like.
Who Can Experience This Condition?
Sinus Arrhythmia can occur in both men and women at any age, though it is more common and often found in children. Without ample cardiovascular exercise, however, RSA gradually disappears as the kids reach their teens. It seems that RSA needs a strong healthy heart to be present; RSA can also be found in runners, swimmers, bicyclists, and the like – healthy adult men and women with excellent cardiovascular conditions.
People who are doing breathing exercises and meditation like yoga can also experience this condition, but only temporarily. As with children, RSA in adults also becomes less noticeable with age. The condition also disappears in men and women with diabetes, hypertension, cardiomegaly and other such cardiovascular diseases.
What Are the Causes of This Syncopation?
Normal heart rate and rhythm are controlled by the cardiovascular center found within the brainstem or medulla oblongata. The increase of heart rate is controlled by the sympathetic nervous system – or the “fight and flight” system – via the accelerator nerve. Stimulation of this nerve increases the firing rate of the SA node, which consequently increases the heart rate. The decrease is controlled by the parasympathetic nervous system – or the “rest and relaxation” system – via cranial nerve X, or the vagus nerve. Stimulation of the vagus nerve decreases the SA node’s firing rate effectively decreasing the heart rate.
Although the existence of RSA has been proven and is well-documented, it is a normal occurrence with a yet unknown cause. The most popular explanation of the occurrence of RSA is that the accelerator nerve gets stimulated during inspiration while the vagus nerve remains unstimulated. And during exhalation, the vagus nerve is stimulated, but not the accelerator nerve. However, there have been studies showing that RSA and vagus nerve stimulation might not be associated with one another after all, and that there may be a different control involving respiration and the cardiac rate.
Are There Any Effects for Having This Condition?
As RSA is a normal condition, it does not have any untoward or ill effect in the body. Given that this phenomenon is usually found in children and physically active adults, some scientists even think that RSA is beneficial.
Previous studies seem to support this belief, as past researches show that it may have a role in the improvement of effective pulmonary gas exchange. The slowing of the heart rate during each expiration or exhalation in the respiratory cycle could be a form of energy saving measure. By suppressing beats during ineffective ventilation and tissue perfusion, sinus arrhythmia could be a child and healthy adult’s means of conserving its expenditure of stored energy.
As with any medical condition, proper consult with medical professionals should be the priority of any person experiencing abnormal signs and symptoms. However, not all seemingly unusual conditions cause a threat to the body, as with sinus arrhythmia. Though further studies have to be done to fully understand this biological phenomenon, the knowledge that it can only be found in children and healthy individuals strongly hint the truth towards that belief. If this is the case, people who are experiencing this condition should consider themselves lucky.
On the other hand, people should not think that having sinus arrhythmia alone is already a sign of overall good health. There are many ways an excellent cardiovascular state can manifest itself, and optimum health requires so much more than just having a healthy heart. People should also take into consideration that there are other factors that affect this phenomenon, such as age; quite possibly there could be other factors that haven’t shown up in studies and research just yet. In furtherance of the musical analogy, the quality of sound produced by one section or individual by itself cannot vouch for the overall musical piece’s beauty. Good health is a result of each and every system, organs or cells working together to achieve a beautiful, harmonious symphony of wellbeing – and that is music to the ears.