Tachycardia refers to an abnormally faster resting heart rate, which can produce symptoms, like palpitations, chest pain, and dizziness. Find out more about this condition, and the symptoms produced by it, in this HealthHearty article.
Tachycardia refers to an abnormally faster heart rate at rest, i.e., a heart rate that exceeds the normal range for a resting heart rate. The resting heart rate is the heart rate when a person is sleeping or not doing any activity. Tachycardia refers to a faster than normal resting heart rate. In adults, the normal resting heart rate is 60 to 100 beats per minute. When the heart rate exceeds this normal range, the condition is known as tachycardia.
This condition is mainly caused by the transmission of rapid electrical signals across the heart tissues. The electrical signals or impulses are generated at the sinus node, located in the right atrium, from where the signals travel across the atria and the ventricles. These signals cause the heart muscles to contract, and thereby enable the heart to pump blood from the atria to the ventricles, and from the ventricles to the lungs and the entire body. But when the heart beats quite rapidly, it fails to pump blood effectively. This can reduce the flow of blood to the entire body, including the heart.
Basically, this condition can be of three types, depending on the point from where it originates. Ventricular tachycardia originates from any of the ventricles, while in the case of supraventricular tachycardia, the faster heart rhythm starts above the ventricular tissue.
Supraventricular tachycardia can begin from the atria or the AV node. On the other hand, sinus tachycardia originates from the sinus or sinoatrial node. It is mainly caused by conditions, like stress, anxiety, physical exertion, fever, hyperthyroidism, hypoxia, anemia, electric shock, sepsis, and heart failure.
It can also be observed in people who drink a lot of caffeinated beverages, and take nicotine, cocaine, and certain other medications. Basically, an abnormally faster heart rate can be caused by any factor that can disrupt the electrical signals that regulate the heart rhythm.
Supraventricular tachycardia has been observed to be associated with conditions, like heart failure, thyroid disease, pericarditis, smoking, high blood pressure, atherosclerosis, pulmonary emboli, alcohol and drug abuse, excessive intake of caffeine and certain drugs. Ventricular tachycardia can be caused by heart failure, myocarditis, valvular heart disease, changes in blood pH, heart surgery, and certain anti-arrhythmic medications.
This condition may not exhibit any symptom at times. If symptoms are present, they usually appear all of a sudden, and then last for a few minutes to a day or two. Sometimes, the symptoms can last for days until the condition is treated. The most common symptoms of supraventricular and atrial tachycardia are:
- Palpitations, which can be felt as a rapid heartbeat in the throat or the chest.
- Rapid pulse rate
- Chest pain or pressure
- lightheadedness or dizziness
- Shortness of breath
- Fainting or syncope (in severe cases)
If tachycardia originates in the ventricles, then one can experience the following symptoms:
- Angina or chest pain
- Fainting or syncope
Sinus tachycardia is generally asymptomatic, or it can produce some minor symptoms like:
- Palpitations, which can give a feeling of heart pounding in the chest
- Chest pain (quite sharp at times) and tightness in the chest
- Increased fatigue
- Exercise intolerance
So, basically the symptoms of the different types of tachycardia, including the paroxysmal tachycardia, are more or less similar. Paroxysmal tachycardia can be supraventricular or ventricular. This condition is characterized by sudden occurrence and disappearance. In other words, the condition begins and subsides in an acute or paroxysmal manner.
This condition is usually diagnosed by evaluating the symptoms, along with carrying out a physical examination, electrocardiogram, and some additional tests. The treatment of this condition mainly depends on its type and severity. Sometimes, a simple maneuver, such as washing the face with cold water or putting an icepack on the face, as well as holding the breath for a while, and even coughing can help resolve an episode of tachycardia, especially the paroxysmal tachycardia.
However, medications such as anti-arrhythmic drugs may be required to slow down the heartbeat, if the condition is quite severe. Occasionally, an electric shock may be needed to regulate the heartbeat, especially in the case of ventricular tachycardia. Apart from these, some other treatment options for this condition are, implantation of cardioverter-defibrillator, radiofrequency catheter ablation, and open heart surgery.
This condition can sometimes lead to certain major complications, like formation of blood clots and heart failure. People having heart and cardiovascular diseases should remain vigilant against this condition, and inform their physicians as soon as possible, if they experience any of the aforementioned symptoms.
Disclaimer: This article is for informative purposes only, and should not be treated as a substitute for professional medical advice.