What is tachycardia?
Tachycardia refers to a high resting heart rate. In adults, the heart usually beats between 60 and 100 times per minute.
Doctors usually consider a heart rate of over 100 beats per minute to be too fast, though this varies among individuals. Factors such as age and fitness levels can affect it.
When tachycardia is present, either the upper or lower chambers of the heartbeat significantly faster.
When the heart beats too rapidly, it pumps less efficiently. Blood flow to the rest of the body, including the heart, reduces.
Also, when the heart beats faster, the heart muscles need more oxygen. In time, oxygen-starved cells can die, leading to a heart attack.
Types of tachycardia
Atrial or Supraventricular Tachycardia (SVT)
Atrial or supraventricular tachycardia (SVT) is a fast heart rate that starts in the upper chambers of the heart. Some forms of this particular tachycardia are paroxysmal atrial tachycardia (PAT) or paroxysmal supraventricular tachycardia (PSVT).
With atrial or supraventricular tachycardia, electrical signals in the heart’s upper chambers fire abnormally. This interferes with electrical impulses coming from the sinoatrial (SA) node, the heart’s natural pacemaker.
The disruption results in a faster than normal heart rate. This rapid heartbeat keeps the heart’s chambers from filling between contractions, which compromises blood flow to the rest of the body
A profile for atrial or SVT
In general, those most likely to have atrial or supraventricular tachycardia are:
- SVT is the most common type of arrhythmia in kids
- Women, to a greater degree than men
- Anxious young people
- Physically fatigued people
- People who drink large amounts of coffee
- Heavy alcohol drinking
What are the causes of tachycardia?
Strenuous exercise, a fever, fear, stress, anxiety, certain medications, and street drugs can lead to sinus tachycardia. It can also be triggered by anaemia, an overactive thyroid, or damage from a heart attack or heart failure.
Supraventricular tachycardia is most likely to affect people who smoke, drink too much alcohol, or have a lot of caffeine. In some cases, it’s linked to heart attacks. It’s more common in women and children.
The ventricular type is associated with abnormal electrical pathways that are present at birth, structural heart problems such as cardiomyopathy or coronary heart disease, medications, or electrolyte imbalance. Sometimes the reason is not clear.
Symptoms of tachycardia
Tachycardia can be part of the body’s normal rejoinder to anxiety, fever, fast blood loss, or strenuous exercise. It can also be caused by medical problems, such as an abnormally high level of thyroid hormones, called hyperthyroidism. In some people, tachycardia is the result of cardiac arrhythmia (an abnormality of the heart rate or rhythm generated by the heart). Tachycardia can also be caused by lung problems, such as pneumonia or a blood clot in one of the arteries of the lung.
In other cases, this can be a side effect of some foods and drinks, such as coffee, tea, alcohol, and chocolate, tobacco.
The treatment options will depend on various factors, including:
- The cause
- The age of the person
- Their overall health
Treatment aims to address the cause, but a doctor may also try to:
- Slow the heart rate
- Prevent further episodes
- Reduce the risk of complications
If there is no clear underlying cause, it may take some time to find a suitable treatment option.
Medicines to treat tachycardia
Medicines used to reduce the heart rate:
- Digitalis or digoxin
Medicines used to maintain a regular heart rhythm:
Medicines used to prevent blood clots and help reduce the risk of stroke:
Anticoagulants such as:
If a person seeks medical advice for a suspected heart rhythm problem, the doctor will:
- Ask about their symptoms
- Carry out a physical exam
- Order some tests
These tests may include:
- Electrocardiogram: Electrodes attached to the skin can measure electrical impulses that the heart produces.
- Echocardiogram: This is a type of ultrasound test that produces a moving image of the heart.
- Wearable devices: The person can carry a Holter monitor or event recorder. These devices can monitor heart rhythms or electrical impulses.
- Blood tests: These helps to determine whether thyroid or other problems are contributing to this disease.
Ageing or having a family history of tachycardia or another heart rhythm disorder increases the chances of developing tachycardia. Any condition that puts pressure on the heart or damages heart tissue can increase the risk of heart disease. Such conditions include:
- Heart disease
- Excessive alcohol consumption
- Excessive use of caffeine
- Overactive or underactive thyroid
- Psychological stress or anxiety
- Sleep apnea
Lifestyle changes or medical treatment for health-related conditions can lower your risk.
Complications of tachycardia
Complications are depends on the type of tachycardia, how fast your heart beats, how long the fast heart rate lasts, and if you have other heart conditions.
Possible complications include:
- Blood clots can reason a stroke or heart attack.
- The inability of the heart to pump sufficient blood (heart failure).
- Frequent fainting or loss of consciousness.
- Sudden death, habitually only related to ventricular tachycardia or ventricular fibrillation.
The most effective way is to maintain a healthy heart and reduce your risk of developing heart disease. If you already have heart disease, monitor it and follow your treatment plan to help prevent tachycardia.
Prevent heart disease
Treat or eliminate risk factors that may lead to heart disease. Take the following steps:
- Exercise and eat a healthy diet. Live a heart-healthy lifestyle by exercising regularly and eating a healthy, low-fat diet that’s rich in fruits, vegetables and whole grains.
- Maintain a healthy weight. Being overweight increases your risk of developing heart disease.
- Keep blood pressure and cholesterol levels under control. Make lifestyle changes and take medications as prescribed to correct high blood pressure (hypertension) or high cholesterol.
- Stop smoking. If you smoke and can’t quit on your own, talk to your doctor about strategies or programs to help you break a smoking habit.
- Don’t use recreational drugs. Don’t use stimulants, such as cocaine. Talk to your doctor about an appropriate program for you if you need help ending recreational drug use.