To diagnose ventricular tachycardia, your doctor may review your symptoms and your family and medical history and conduct a physical examination.
Your doctor may order several tests to diagnose your condition, determine the cause and severity of your condition, and determine the most appropriate treatment.
In some cases, ventricular tachycardia may be a medical emergency and require an urgent diagnosis and prompt treatment.
Several heart tests also may be necessary to diagnose ventricular tachycardia.
An electrocardiogram, also called an ECG or EKG, is the most common tool used to diagnose ventricular tachycardia. It's a painless test that detects and records your heart's electrical activity using small sensors (electrodes) attached to your chest and arms.
An ECG records the timing and strength of electrical signals as they travel through your heart. Your doctor can look for patterns among these signals to determine what kind of tachycardia you have and how abnormalities in the heart may be contributing to a fast heart rate.
Your doctor may also ask you to use portable ECG devices at home to provide more information about your heart rate. These devices include:
Holter monitor. This portable ECG device is carried in your pocket or worn on a belt or shoulder strap. It records your heart's activity for an entire 24-72 hour period, which provides your doctor with a prolonged look at your heart rhythms.
Your doctor will likely ask you to keep a diary during the same 24 hours. You'll describe any symptoms you experience and record the time they occur.
Event monitor. This portable ECG device is intended to monitor your heart activity over a few weeks to a few months. You wear it all day, but it records only at certain times for a few minutes at a time.
With many event monitors, you activate them by pushing a button when you experience symptoms of a fast heart rate. Other monitors automatically sense abnormal heart rhythms and then start recording. These monitors allow your doctor to look at your heart rhythm at the time of your symptoms.
- Transtelephonic monitor. This device provides continuous heart rhythm monitoring but must be worn continuously. It may or may not include wires.
- Implantable loop recorder. This is an implantable device that has no wires and can sit underneath your skin for up to three years to continuously monitor your heart rhythm.
Imaging of the heart may be performed to determine if structural abnormalities are affecting blood flow and contributing to ventricular tachycardia.
Types of cardiac imaging used to evaluate V-tach include:
- Echocardiogram (echo). An echocardiogram creates a moving picture of your heart using sound waves via a transducer placed on the chest that emits and detects these waves. An echo can identify abnormalities in the heart valves and heart muscle that contribute to poor blood flow.
- Magnetic resonance imaging (MRI). A cardiac MRI provides still or moving pictures of how the blood is flowing through the heart and detects irregularities. It is often used to evaluate potential causes of ventricular tachycardia.
- Computerized tomography (CT). CT scans combine several X-ray images to provide a more detailed cross-sectional view of the heart.
- Coronary angiogram. This may be used to study the flow of blood through your heart and blood vessels. Your doctor may use a coronary angiogram to reveal potential blockages or abnormalities. It uses a dye and special X-rays to show the inside of your coronary arteries.
- Chest X-ray. This painless test is used to take still pictures of your heart and lungs and can detect if your heart is enlarged.
Your doctor may recommend a stress test to see how your heart functions while it is working hard during exercise or when medication is given to make the heart beat faster.
In an exercise stress test, electrodes are placed on your chest to monitor heart function while you exercise, usually by walking on a treadmill. Other heart tests may be performed in conjunction with a stress test.
Your doctor may recommend an electrophysiological test to confirm the diagnosis or to pinpoint the location of problems in your heart's circuitry.
During this test, a doctor inserts thin, flexible tubes (catheters) tipped with electrodes into an access point, usually your groin or neck, and guides them through your blood vessels to various spots in your heart.
Your doctor may order additional tests as needed to diagnose an underlying condition that is contributing to ventricular tachycardia and judge the condition of your heart.
The goals of ventricular tachycardia treatment are to restore your normal heart rhythm, regulate your heart rate and prevent future episodes.
Treatment of V-tach depends largely on what is causing the arrhythmia and the type or severity of your ventricular tachycardia.
The two main types of ventricular tachycardia are those that resolve on their own within 30 seconds (nonsustained V-tach ) and those that last more than 30 seconds, interfere with normal blood flow or require medical intervention to resolve (sustained V-tach).
Urgent V-tach treatment
Sustained ventricular tachycardia may sometimes lead to sudden death and often requires urgent medical intervention.
Immediate treatment usually involves restoring a normal heart rate by delivering a jolt of electricity to the heart via defibrillation or cardioversion but can also involve providing medications orally or intravenously.
Defibrillation may be performed using an automated external defibrillator (AED) by a bystander who recognizes the signs of cardiac arrest, or by medical professionals using paddles in a hospital setting. Cardioversion is performed in a hospital setting using a cardioversion machine that monitors your heart rhythm before and after shocks are delivered.
An injection of an anti-arrhythmic medication, such as lidocaine, may also be used to treat sustained ventricular tachycardia and restore a normal heart rhythm.
Preventing episodes of a fast heart rate
People with nonsustained or sustained ventricular tachycardia may be treated in a variety of ways to prevent future episodes and related complications. Treatments for V-tach include:
Catheter ablation. This procedure is often used when a discrete electrical pathway is responsible for an increased heart rate.
In this procedure, a doctor inserts catheters into your groin or neck and guides them through the blood vessels to your heart. Electrodes at the catheter tips can use heat, extreme cold or radiofrequency energy to damage (ablate) the extra electrical pathway and prevent it from sending electrical signals.
- Medications. Anti-arrhythmic medications may prevent a fast heart rate when taken regularly.
Implantable cardioverter-defibrillator. If you're at risk of having a life-threatening ventricular tachycardia episode, your doctor may recommend an implantable cardioverter-defibrillator (ICD).
The device, about the size of a pager, is surgically implanted in your chest. The ICD continuously monitors your heartbeat, detects an increase in heart rate and delivers precisely calibrated electrical shocks, if needed, to restore a normal heart rhythm.
A new type of ICD called a subcutaneous implantable cardioverter-defibrillator (S-ICD) is less invasive but larger in size than an ICD. Your doctor implants the S-ICD under the skin at the side of the chest below the armpit. It's attached to an electrode that runs along your breastbone. You may be a candidate for an S-ICD if you have structural defects in your heart that prevent advancing wires to the heart through your blood vessels, or if you have other reasons for wanting to avoid traditional ICDs.
- Surgery. Open-heart surgery may be needed in some cases to treat a process contributing to ventricular tachycardia (for example, if there are blockages in blood vessels). Surgery is usually used only when other treatment options don't work or when surgery is needed to treat another heart disorder.
Treating an underlying disease
If another medical condition is contributing to ventricular tachycardia, such as some form of heart disease, treating the underlying problem may prevent or minimize ventricular tachycardia episodes.
Coping and support
If you have a plan in place to deal with an episode of a fast heartbeat, you may feel calmer and more in control when one occurs. Talk to your doctor about:
- How to take your pulse and what a normal pulse rate is for you
- When and how to use a variety of maneuvers or take additional medications if they are appropriate for you
- When to call your doctor
- When to seek emergency care
Preparing for your appointment
Make a list ahead of time that you can share with your doctor. Your list should include:
- Symptoms you've experienced, including any that may seem unrelated to your heart
- Key personal information, including any major stresses or recent life changes
- Medications, including vitamins or supplements
- Questions to ask your doctor
List your questions from most important to least important in case time runs out. Basic questions to ask your doctor include:
- What is likely causing my fast heart rate?
- What kinds of tests do I need?
- What's the most appropriate treatment?
- What kind of risks does my heart condition create?
- How will we monitor my heart?
- How often will I need follow-up appointments?
- How will other conditions I have or medications I take affect my heart problem?
- Do I need to restrict my activities?
- Are there any brochures or other printed material that I can take home with me? What websites do you recommend visiting?
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask additional questions.
What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on. Your doctor may ask:
- When did you first begin experiencing symptoms?
- How often have you had episodes of a fast heartbeat?
- How long have the episodes lasted?
- Does anything, such as exercise, stress or caffeine, seem to trigger or worsen episodes?
- Does anyone in your family have heart disease or a history of arrhythmias?
- Has anyone in your family experienced cardiac arrest or died suddenly?
- Do you smoke?
- How much alcohol or caffeine do you use?
- Do you use recreational drugs?
- Are you being treated for high blood pressure, high cholesterol or other conditions that may affect your circulatory system?
- What medications do you take for these conditions, and do you take them as prescribed?