Ventricular tachycardia (VT) is a disorder where the heart beats faster than normal. It is caused when the electrical signals from the ventricles are irregular. For a person at rest, a normal heart rhythm usually ranges between 60 to 100 beats per minute (bpm); someone experiencing ventricular tachycardia might experience a heartbeat of 100 or greater beats per minute. The typical heart rate for those afflicted with VT is 170 bpm or more.
The ventricles (lower chambers of the heart) are where ventricular tachycardia starts. It is a serious condition because it can lead to ventricular fibrillation, whereby the heart no longer pumps blood, leading to sudden death.
What are the causes of ventricular tachycardia?
The causes of ventricular tachycardia are both unknown and known, depending on the type of case. When ventricular tachycardia affects younger people, the causes are generally unclear. However, the majority of cases are attributed to heart disease.
The types of heart disease that can increase one’s risk for ventricular tachycardia include heart attacks, congenital heart defects, hypertrophic or dilated cardiomyopathy, valvular heart disease, and myocarditis. If scar tissue has formed in the ventricle muscles, regardless of the time following a heart attack, a person will be at a greater risk of ventricular tachycardia.
Other causes of ventricular tachycardia include anti-arrhythmic drugs, blood chemistry changes, acid-base (pH) changes, and oxygen deprivation. Medications and recreational drugs (cocaine, etc.) can also be contributing factors to VT.
Types of ventricular tachycardia
There are several different types of ventricular tachycardia, which depend on how long the heart beats irregularly, the kind of heartbeat pattern that is demonstrated, and the way the heart is able to pump blood.
Nonsustained VT stops suddenly and does not cause blood flow problems. A sustained VT is defined as lasting longer than 30 seconds; it also will cause a decrease in the flow of blood. Monomorphic VT is defined by the heartbeat pattern whereby each heartbeat resembles the next heartbeat. Finally, in a polymorphic case of VT, the heartbeats vary in amplitude, axis, and duration.
Symptoms, risk factors, and complications of ventricular tachycardia
Symptoms of ventricular tachycardia arise when there is insufficient blood flow to the entire body. These may include dizziness, lightheadedness, palpitations, shortness of breath, or chest pain. However, be warned that VT may not produce any symptoms in afflicted individuals.
If a condition strains or damages the heart, it increases your risk of developing VT. Therefore, heart disease, a family history of heart disease, medication side effects, recreational drug abuse, and severe electrolyte abnormalities all place you at a higher risk of VT.
The complications associated with VT can be very serious: An elevated heart rate or VT that is prolonged for a period greater than seconds can cause fainting, a person to lose consciousness, cardiac arrest, and even death.
How to diagnose ventricular tachycardia
Diagnosis of ventricular tachycardia is done by a medical doctor. Typically, an MD would take an inventory of all of your symptoms, review both your family and medical history, and then perform a physical exam. Additional tests may be administered, such as:
Electrocardiogram (ECG or EKG)
An ECG is a widely-used tool that can diagnose VT. All it involves is attaching an electrode to your chest and arms and recording your heart’s activity. There are also portable ECG units that can continually monitor your heart rate for more extended periods of time such as holter monitors, event monitors, transtelphonic monitors, and implantable loop recorders.
To determine whether or not abnormalities in the structure of the heart are causing VT, cardiac imaging may be used. Several types of cardiac imaging can be used, including echocardiogram, magnetic resonance imaging (MRI), computerized tomography, coronary angiogram, and chest x-ray.
A stress test is where electrodes are attached to your chest while you are asked to perform simple exercises (ie: walking on a treadmill, riding a stationary bicycle). Exercise allows a better picture of the heart because it makes your heart pump harder and faster. In this way, a doctor can monitor the blood flow to your heart when you are performing more strenuous activity.
When a doctor wants to find out the exact area of your heart where a problem may be originating from, they may ask for an electrophysiological test. Catheters with electrodes on their tips are inserted into the body (usually in either the groin or neck), with their progress viewable through a video screen. Electric pulses are then sent through the catheters to get your heart to beat at different speeds; the catheters then record your heart’s electrical signals to determine where any irregularities are occurring.
Treatment options for ventricular tachycardia
Treatment options for ventricular tachycardia that all depend on the cause and status of the condition. Sustained or nonsustained VT can be treated by radiofrequency catheter ablation, whereby a catheter is inserted into the body to stop an extra electrical pathway from sending signals; anti-arrhythmic medications; implanting a cardioverter-defibrillator (ICD) into the chest, or surgery may be needed to deal with an issue that is contributing to VT.
In an emergency situation, the heart rate can be returned to normal by using CPR, an electric defibrillator, and medications administered intravenously.
How to prevent ventricular tachycardia
The absolute best way to mitigate the risk of developing ventricular tachycardia is by reducing your risk of getting cardiovascular diseases. This means that care should be taken to live a healthy lifestyle that proactively preserves the condition of your body. Prevention starts with undertaking actions towards the goal of overall health.
Healthy lifestyle changes
Start with looking at your nutrition, with special attention to including fruits, vegetables, and whole grains in your diet. Attempt to curb consumption of sweets, sugary drinks, and other items that are not an ideal source of nutrition. This will allow you to maintain a better weight, which in turn reduces your risk for heart disease.
Drugs such as tobacco, alcohol, or other recreational drugs should only be taken in safe amounts or eliminated entirely. If you smoke, consider looking at methods or programs designed to help you quit, such as nicotine patches, support groups, behavioral therapy, medication or other combinations of these approaches. Consume alcohol without being excessive, and if alcoholism is a problem, consider a treatment program that will be effective.
Avoid OTC medications that will affect your heartbeat, especially cough medicine that contains pseudoephedrine. Also, try to limit caffeine intake, perhaps only having one or two coffees per day. Finally, by limiting stress in your life, your body will respond positively on a physiological level.
Monitor your heart
You may already have developed heart disease or associated conditions. Keep in mind, you are not powerless – you have many tools available at your disposal that will allow you to keep your condition(s) in check.
If you have been prescribed a plan of treatment, make sure that you study it and are able to readily execute it. If your symptoms change, worsen, or you experience new symptoms, then you should consult your doctor immediately.
Dizziness, shortness of breath, lightheadedness, palpitations, chest pain, angina, and seizures are not signs that should be ignored. If you are experiencing any of the aforementioned symptoms, have existing heart disease, or a family history of heart issues, then ventricular tachycardia may be on your radar. Remember that more serious symptoms like loss of consciousness, cardiac arrest, and even death are potential outcomes if you have VT. Seek out a medical doctor to get a proper diagnosis and to learn what may be afflicting you.
It is important to make healthy lifestyle changes in order to have a stronger, healthier cardiovascular system. This will rule out a wide range of diseases and conditions beyond VT. Always remember, even if you are suffering from ventricular tachycardia or other heart ailments, there is help and resources to get you on track and healthy.
Related: Why your heart skips a beat