Different types of tachycardia have different causes. Ventricular fibrillation, for example, is often associated with heart attacks. On the other hand, most other types, such as supraventricular and ventricular tachycardia are caused by misfired electrical signals in a certain area of the heart people are often born with these conditions.
There are some activities that increase the risk of triggering an episode of tachycardia. However, even anxiety and stress can cause tachycardia. Also, strenuous exercises, especially when you aren't used to exercise, could push your heart into tachycardia. Treatments depend on the severity and type of tachycardia.
In many cases, vagal maneuvers work well to stop an episode of tachycardia. These maneuvers affect the vagal nerve, which helps regulate heartbeat. Vagal maneuvers include coughing, bearing down, placing your face in ice water, and massaging the vagal nerve. If the vagal maneuvers don't work, you may have to go to the hospital for antiarrhythmic medications, which are designed to help restore a regular heartbeat. In the event of ventricular fibrillation, however, only an electric shock can knock the heart out of tachycardia.
You may also be able to prevent future tachycardia attacks with certain medications or surgery. Tachycardia is often harmless and goes away on its own. A person with PSVT can have a heart rate as high as beats per minute bpm. A normal rate is between 60 and bpm. There are medications and procedures that may be necessary in some cases, especially where PSVT interferes with heart function.
PSVT affects about 1 in every 2, children. It is the most frequent abnormal heart rhythm in newborns and infants. PSVT is more common in adults under age Adults over age 65 are more likely to have atrial fibrillation AFib. In a normal heart, the sinus node directs electrical signals through a specific pathway. This regulates the frequency of your heartbeats.
An extra pathway, often present in supraventricular tachycardia, can lead to the abnormally fast heartbeat of PSVT. There are certain medications that make PSVT more likely. For example, when taken in large doses, the heart medication digitalis digoxin can lead to episodes of PSVT. The following actions can also increase your risk of having an episode of PSVT:. Read more: Digitalis toxicity: The deadly potential of digitalis ». In more serious cases, PSVT can cause dizziness and even fainting due to poor blood flow to the brain.
Sometimes, a person experiencing symptoms of PSVT may confuse the condition with a heart attack. If your chest pain is severe you should always go to the emergency room for testing. If you have an episode of fast heartbeats during an examination, your doctor will be able to measure your heart rate. This is an electrical tracing of the heart. It can help determine which type of rhythm problem is causing your fast heart rate.
PSVT is only one of many causes of abnormally fast heartbeats. Both her pediatrician and a specialist have told us that her tachycardia is not dangerous.
However, when I hear reports of young people dying of heart arrhythmias, I become frightened all over again. How can I reassure myself that this is not dangerous? Answer from Blair Halperin , M. Tachycardia means nothing more than fast heart rate tachy means fast, and cardia has to do with the heart. There are several types of tachycardia.
There are also abnormal types, where the heart seems to speed up for no reason. These tachycardias are a type of arrhythmia — a heart rhythm disorder, usually caused by a glitch in the electrical system that controls the heartbeat.
This produces a short circuit, which causes the fast heartbeat. SVT is usually triggered by extra heartbeats ectopic beats , which occur in all of us but may also be triggered by:. The heart has two upper chambers the left and right atria and two lower chambers the left and right ventricles. The atria and ventricles have walls of muscle. A heartbeat happens when this muscle suddenly contracts tightens so that the chambers become smaller and the blood inside is squeezed out.
The control of the heartbeat starts with a small clump of cells in the right atrium, called the sinoatrial node the heart's natural pacemaker. This sends out electrical impulses through the atrial muscle to another clump of cells called the atrioventricular AV node, found between the atria and ventricles. The impulse then continues through the AV node down fibres that conduct the impulse into the muscle of the ventricles. The AV node determines the rate of contraction of the ventricles.
The pulse felt at the wrist is due to the contraction of the ventricles. If your GP suspects that you have supraventricular tachycardia SVT , they may ask you to have an electrocardiogram and refer you to a heart specialist. An electrocardiogram ECG is a test that records the rhythm and electrical activity of your heart.
Small stickers electrodes are stuck to your arms, legs and chest, and connected via wires to an ECG machine. Every time your heart beats, it produces tiny electrical signals. An ECG machine traces these signals onto paper. Your heart rate during SVT may be as high as beats per minute, but is usually between and ECGs are usually done in hospital or in your GP's surgery.
It takes about five minutes and is painless. The diagnosis of SVT can then be confirmed and other conditions ruled out. However, it may be difficult to capture an attack.
So your doctor may ask you to wear a small, portable electrocardiogram monitor that will record your heart rate either continuously over 24 hours, or when you switch it on at the start of an attack. Further tests may be done once episodes of SVT are confirmed. These aim to determine the exact location within the heart that is triggering the episodes of SVT. For example, you may be asked to take part in a electrophysiology study done under sedation, in which doctors pass electrodes soft flexible wires up through a vein in your leg to your heart.
These electrodes measure the electrical signals in your heart and enable doctors to determine where the abnormal signals are coming from. In many cases, the symptoms of supraventricular tachycardia SVT stop quickly and no treatment is needed. If treatment is needed, you will have to go to hospital.
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