Supraventricular Tachycardia (SVT), a common heart condition, is caused by an early atrial beat that sends an electrical impulse along an abnormal path to the ventricles. Essentially, the heart has a normal flow of blood and when an abnormal signal is fired at random the system is interrupted and the heart begins beating at a dangerously fast rate between 140 and 250bpm, as opposed to a normal heartbeat of 60-100bpm.
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The heart always pumps blood from the body through the superior and inferior vena cava’s to fill the right atrium before it is pumped into the right ventricle then to the lungs, etc. The misfire in the electrical circuit of the heart causes the atria to beat without allowing for the right atrium to fill all the way with blood before pumping it on to the right ventricle.
Paroxysmal supraventricular tachycardia (PSVT) is one specific type of atrial tachycardia. This type is commonly caused by anxiety, stimulants, and an overactive thyroid. PSVT is mainly found in women and children; it is common to see PSVT occur with the onset of menstruation in some women. The symptoms of SVT though one may think are fatal, are usually more annoying than deadly. Symptoms frequently include: lightheadedness, chest pain, palpitations, anxiety, sweating, and shortness of breath. Sometimes the heart can develop extra cardiac muscle if SVT occurs often because it is being used more than if a normal blood flow was occurring.
An electrocardiogram (ECG) is used to diagnose SVT. It measures the heart’s rhythm and electrical activity and can record SVT episodes if necessary. Cardiologists like to monitor these conditions for a period of time before diagnosing individuals. After getting an ECG at a hospital or doctor’s office, a cardiologist may recommend the patient carry with them a portable ECG for a day or two. The portable ECG is a small device that straps on to the patient and can be turned on when an episode is occurring. It is important to look at the time when an SVT episode begins and ends. This assists in predicting when others may occur and helps doctors better understand the condition.
An episode can temporarily be stopped by holding one’s breath or plugging the nose and mouth and breathing out or bearing down. If those measures do not work SVT can also be stopped by injecting adenosine into the patient’s system or if the condition is serious electrical shock may be necessary. One way to permanently halt supraventricular tachycardia is catheter ablation. Catheter ablation is a procedure that is performed in a hospital where a doctor places catheters in a vein (by the groin or sometimes in the neck) and guides them to the heart. When the catheters have reached the heart the electrodes on the catheters record the electrical activity in order for the doctor to find the best place to place the ablation. Special catheters are then used to transmit either electrical signals or cold temperature to the specific area. By doing this scar tissue forms which block the electrical signals that cause SVT. Like most procedures, this one is not 100% effective, there is always a chance that the symptoms of SVT come back.
Though SVT is a common condition with minimal life threatening symptoms most people do not know what it is or how to help a person when they are experiencing an episode. It is best for the person affected by SVT to stop what they are doing tell someone that they are experiencing an episode and sit or lay down on the ground in order to protect themselves if they were to lose consciousness. It is not necessary to call an ambulance if the person is in a reasonable condition, but if they were to lose consciousness or ask for medical assistance it is in their best interest to have someone call medical professionals. So who knew a heart disease could be so harmless?