Tachycardia: Faster Heart Beat, But Less Blood Flow
Tachycardia is a condition where a person’s heart is beating abnormally fast. When we become more active our heart rate increases to meet the increased demand of oxygen from muscles. As such, tachycardia is usually not a problem as the heart rate will return to the resting rate once the activity stops. Occasionally, because of a malfunction with the heart’s electrical system, the heart rate stays high or climbs even higher.
Tachycardia can also occur at rest. For example, instead of the person’s resting heart rate remaining between 60-80 beats per minute, which is the norm, it increases without a physiological need. In other words, there is no increase in blood flow demand, yet the heart rate increases as if there was. Officially, tachycardia is when a resting heart rate is above 100 beats per minute. However, everyone is a little different and if you think you have an abnormally high heart rate you should speak to your physician about it. Keep in mind that children will have a faster normal heart rate than adults.
From a physiological perspective, if the heart beats too fast there isn’t enough time in between heart contractions for blood to refill the heart chambers. As a result, and counter-intuitively, the heart will be pumping less blood than normal even though it is beating very fast.
Uncontrolled tachycardia can result in arrhythmia or fibrillation, an irregular heart rhythm, which can result in cardiac arrest. So, it does require treatment. Aside from some potential self-help treatments discussed below, tachycardia isn’t a condition that is treatable with standard first aid techniques.
In cases where the person has collapsed and may be suffering from fibrillation, a defibrillator will be needed to restore regular heart rhythm.
Some people with chronic tachycardia may require daily medication or a pace maker.
There are some non-invasive tests to determine if you have it, e.g. an ECG (Electrocardiogram) where electrodes are attached to specific points on the chest to monitor the heart’s electrical impulses and heart rate. Usually an ECG can be done at a clinic, however, your physician may ask you to wear a device that will monitor your heart rate for several hours or for several days. This way they can observe the measurements over a longer time frame and obtain a more accurate diagnosis. It is also possible that a certain trigger, such as a specific stressor, encountered during your daily activities, may cause tachycardia.
According to the Mayo Clinic, there are additional tests that can be done as well. For example, there is the electrophysiological test where very thin tubes are inserted into a blood vessel from the groin area. They are guided to various spots in the heart in order to map the spread of electrical impulses so abnormalities can be identified.
The causes of tachycardia can include things such as:
- A mild heart attack that perhaps went undiagnosed. This can result in damaged heart tissue.
- Exercise, although this is not a problem on its own as long as the heart rate returns to normal once the activity has ceased.
- Alcohol or drugs, or sometimes even prescribed medication can have side effects.
- Some kind of congenital heart disease.
- In case of physical injury where there is shock or blood loss the heart rate will increase in an attempt to compensate for the lower blood circulation.
Tachycardia is usually treated with medication designed to restore the heart’s regular rhythm. This medication is referred to as anti-arrhythmic medication. It can come in the form of a pill or an injection by a physician. If a specific trigger is found then obviously avoiding that trigger will also help.
Because the heart rate is controlled by the nervous system, there is a treatment that may help some people with tachycardia. It is referred to as the Vagal maneuver. This involves coughing, squeezing as if you are having a bowel movement, and / or putting an ice pack on your face. This is an attempt to stimulate the Vagas nerve, which is primarily responsible for keeping your heart from racing. Discuss these methods with your physician before trying them on your own.
Note: A pacemaker is not used to treat tachycardia because such a device can only increase heart rate. Therefore, it is used for bradycardia; a lower than normal heart rate.