Sinus bradycardia is the medical term used when a person has a cardiac rate that is lower than 60 bpm or beats per minute. “Sinus” refers to the sinus node or the sinoatrial node, while “bradycardia” means “slow heart”. As it is the heart’s responsibility to pump out blood to supply all the organs and muscle groups, people with a heart rate slower than normal may be experiencing an inadequate blood and oxygen supply to their organs. This is an unwanted event and if left untreated may lead to more serious complications and even death.
It is no question that the heart is one of the most important organs in the body, which is why there are so many idiomatic expressions associated with the heart. People who are dear or held in regard or fondness are also associated with the heart, as well as the main ideas or core principles. Since the heart’s deterioration will involve all the other organs in the body, any and all extra and meticulous care to keep it beating is certainly well justified.
A Happy Heart
The human heart, with its 4 chambers of right and left atria and ventricles along with its valves and network of arteries and veins is a very hardworking muscle, systematically and rhythmically pumping blood all throughout the rest of the organ systems in the entire body. The sinoatrial node – the heart’s natural pacemaker – fires out electrical impulses that trigger the heart to contract and relax, effectively filling and ejecting blood in and out of its chambers with the normal sinus rhythm of 60-100 beats per minute.
There are numerous factors that can affect the heart rate to slow down or speed up to deviate from the normal range. Things such as temperature, activity or rest and of course medical conditions such as diseases and illnesses all have an effect on the heart rate.
What Causes A Happy Heart to Slow Down?
There are plenty of conditions that can alter the heart rate to result in sinus bradycardia. This is often seen in people who have hypothyroidism or those who have an increased intracranial pressure like those with meningitis and head trauma. Seizures can also slow down the heart rate, as well as hypothermia and Rhodotoxin poisoning. Infections such as diphtheria, acute rheumatic fever, or viral myocarditis may cause sinus bradycardia as a secondary effect. Certain drugs can slow the heart rate as well, such as Beta-blockers, quinidine and digitalis. An increase in vagus nerve stimulation – or vagal tone – could also account for the slowing of the heart rate. A diseased sinus node is also a cause for this condition.
There are normal circumstances when people can also experience this condition, such as when lying down or when sleeping. Lying down relieves the pressure from the heart, as the body is parallel and the pull of gravity isn’t as strong as when upright. As for sleeping, many of the body’s functions stop or slow during sleep, as it is the body’s time to recuperate and heal. But as the heart cannot stop its tireless job, the only thing it can manage is to slow down a bit.
Who Can Experience This?
Men, women and children who have the aforementioned diseases and conditions will certainly experience sinus bradycardia; although, interestingly, the condition also manifests itself in certain healthy adults.
Professional athletes, fitness enthusiasts, swimmers and divers – healthy men and women have all been found with a cardiac rate of 50 and below. And it wasn’t due to the fact that these people were sick or ill. They seem to have this condition because of being healthy.
Why Do Healthy People Experience it?
The heart’s main responsibility is to pump oxygen-rich blood to the body. The human body is relative in size from person to person. Depending on the age, sex, race, genetics and other such factors, the heart may have a large expanse of body mass to pump blood to, and remember that it is only as big as the size of a closed fist.
That being said, the heart is a muscle, and all muscles, with sufficient training and exercise, hardens, thickens, and becomes stronger. A slight young man given the task of transporting 5 buckets of water from the top of the mountain to the house by its foot will do the job at a much slower pace than if a physically fit young man who will be able to carry a bucket in each hand while sprinting down the mountain. The heart of a trained individual, hardened and thickened, can pump blood more forcefully and efficiently, therefore eliminating the need for the heart to push in extra pumps.
What Are Its Effects?
Sinus bradycardia manifesting in average, non-athletic people can experience episodes of vertigo, low blood pressure, syncope or faint, dizziness and the feeling of being lightheaded – symptoms of having not enough oxygen in the body, also known as hypoxia.
In healthy adults, however, a slow heart rate doesn’t have any untoward effects. In fact, it may even aid swimmers and divers, as a slow cardiac rate enables the body to endure lower depths and longer periods of having no oxygen.
Can This Be Treated?
The treatment varies from case to case, but slow heart rates are often manageable. In most cases wherein the slow heart rate is the result of an underlying condition, the cardiac rate will return to normal if that condition is treated. Medications can also be given to increase the rate of the heart, being epinephrine in emergency situations. Some people may need an artificial pacemaker installed, as with the case of a diseased sinus node. Other people do not need to seek out treatment.
Should Sinus Bradycardia Be a Concern?
Yes and no. Not everyone who is experiencing sinus bradycardia is afflicted by a disease or medical condition, as healthy people tend to have it as well. However, this does not also warrant that healthy adults should not get concerned if they have this condition. It is better to be sure by consulting a physician and having physical checkups done regularly.