Ventricular arrhythmias begin in the heart's lower chambers, called the ventricles. Normally, a resting heart should beat between 60 and 100 times per minute. When a ventricular arrhythmia occurs, the ventricles beat abnormally fast -- up 300 beats per minute. Unlike an atrial arrhythmia, ventricular arrhythmias can be the most severe and life-threatening arrhythmias.
- Ventricular tachycardia occurs when the ventricles beat abnormally fast, between 100 and 250 beats per minute, occasionally reaching 300 beats per minute. When contractions of the ventricles are rapid, the heart can't completely fill with blood between beats and less blood is pumped through the body. If left untreated, ventricular tachycardia can lead to ventricular fibrillation, where almost no blood is being pumped out of the heart. A ventricular arrhythmia can be a very serious disorder, and if your doctor suspects that you are developing it, you should seek treatment immediately.
Ventricular Tachycardia FAQs
1. What are the symptoms of ventricular tachycardia?
Symptoms can include palpitations, shortness of breath, lightheadedness, angina, and/or syncope (fainting).
2. What causes ventricular tachycardia?
Ventricular tachycardia is typically caused by conditions that lead to scar tissue formation in the heart. Such conditions include:
- Coronary heart disease (CHD) with prior heart attack
- Cardiomyopathy -an enlarged or abnormally thickened heart
- Congenital (inherited) heart disease
- Valve disease
Rarely ventricular tachycardia occurs in otherwise normal hearts. This is called idiopathic ventricular tachycardia.
3. How is ventricular tachycardia diagnosed?
Those suspected to have ventricular tachycardia will be referred to an electrophysiologist. At Boston Medical Center, skilled electrophysiologists use several different tests to help diagnose this, including:
- Electrocardiogram. This device tracks and graphs heart rhythm using electrical signals from the heart.
- Holter monitor. This device monitors and records the heart rhythm continuously for 24-48 hours.
- Event recorder. An event recorder is activated during episodes of fibrillation and records the heart rhythm at that time.
- Electrophysiology (EP) study. In EP testing, a catheter (a thin, flexible tube) equipped with electrodes is used to record the heart's electrical activity to help map that arrhythmia's location.
4. How is ventricular tachycardia treated?
When ventricular tachycardia causes frequent and sustained symptoms, a cardiologist may recommend treatment, such as:
Medical treatments (medications)
Medical therapy. Physicians may use medications to treat ventricular tachycardia. Common medications for suppressing ventricular tachycardia include beta-blockers and a category of drugs referred to as anti-arrhythmic agents.
Interventional treatments (procedures)
Radiofrequency catheter ablation. During ablation, a catheter with an electrode tip is positioned on a small area of heart tissue. The catheter delivers a burst of radiofrequency energy to destroy this tissue, which blocks the extra abnormal pathway.
Implantable cardiac defibrillator (ICD): These small devices are implanted in the upper chest and connected to the heart with wires called leads. The ICD constantly monitors the heart rate, and when the device detects ventricular tachycardia, it electrically stimulates or shocks the heart to normalize its rhythm.