Video coming soon — Dr. Luni explains ventricular tachycardia in plain language
What are ventricular arrhythmias?
Ventricular arrhythmias are abnormal heart rhythms that originate in the ventricles — the heart's main pumping chambers. Unlike arrhythmias that start in the upper chambers (atria), ventricular arrhythmias arise from below, and their significance varies enormously depending on their type, frequency, and the underlying health of the heart.
Part 1: Premature Ventricular Contractions
(PVCs)
PVCs are extra, early heartbeats that originate in the ventricles and interrupt the normal heart rhythm. They are extremely common — most people will have PVCs at some point in their lives, and many are completely unaware of them. On a heart monitor, PVCs appear as wide, unusual-looking beats followed by a brief pause before the normal rhythm resumes.
What do PVCs feel like?
- A skipped beat or a brief pause in the heartbeat
- A heavy thud or "flip-flop" sensation in the chest
- Palpitations — particularly noticeable at rest or when lying down
- Many people feel nothing at all — PVCs are found incidentally on an ECG
When do PVCs need treatment?
The decision to treat PVCs depends on three key factors:
- Symptoms: If PVCs are causing significant, bothersome palpitations that affect quality of life, treatment may be warranted regardless of their frequency.
- PVC burden: PVC burden refers to what percentage of all heartbeats are PVCs. A low burden (under 5-10%) is generally well tolerated. When the burden rises above 10-15% — and particularly above 20-25% — it can begin to weaken the heart muscle over time, even in patients with no symptoms.
- Effect on heart function: If PVCs are causing or contributing to a weakened heart (reduced ejection fraction or PVC-induced cardiomyopathy), treatment is recommended even if the patient feels fine.
For most people, PVCs are benign and require nothing more than reassurance and monitoring. The decision to treat is individualized — based on how you feel, your PVC burden, and whether your heart function is being affected.
Treatment options for PVCs
- Watch and wait: For patients with low PVC burden and no symptoms or effect on heart function, no treatment is needed. Lifestyle factors such as caffeine reduction, stress management, and adequate sleep can reduce PVC frequency.
- Medications: Beta-blockers or calcium channel blockers can reduce PVC frequency and lessen symptoms in many patients.
- Catheter ablation: For patients with high PVC burden, PVC-induced cardiomyopathy, or symptoms that are not controlled with medications, catheter ablation is highly effective. The procedure targets and eliminates the focus in the ventricle responsible for generating the PVCs.
Part 2: Ventricular Tachycardia
(VT)
Ventricular tachycardia is a rapid heart rhythm — typically more than 100 beats per minute — that originates in the ventricles. Unlike PVCs (which are individual extra beats), VT is a sustained or repetitive run of rapid ventricular beats. When the ventricles beat rapidly and independently of the atria, they cannot fill and pump blood efficiently — and this is where VT becomes concerning.
How serious is VT?
The seriousness of VT depends heavily on how long it lasts and what the underlying heart looks like:
- Non-sustained VT (NSVT): Runs of 3 or more rapid ventricular beats that stop on their own within 30 seconds. In patients with a structurally normal heart, NSVT is often benign. In patients with underlying heart disease, it warrants careful evaluation.
- Sustained VT: VT that lasts longer than 30 seconds or causes symptoms such as dizziness, fainting, or hemodynamic instability. Sustained VT is always concerning and requires urgent evaluation and treatment. Longer episodes are more worrying — the heart cannot sustain rapid ventricular rates indefinitely, and sustained VT can degenerate into ventricular fibrillation.
- Idiopathic VT: VT occurring in a structurally normal heart. Generally carries a more favorable prognosis but still requires evaluation and is often very amenable to catheter ablation.
- Scar-related VT: VT arising from scar tissue left by a prior heart attack or cardiomyopathy. This carries higher risk and often requires both an ICD and catheter ablation.
Symptoms of VT
- Rapid, pounding palpitations
- Dizziness or lightheadedness
- Shortness of breath
- Chest pain or pressure
- Fainting (syncope)
- Cardiac arrest in severe cases
- Some short runs of VT cause no symptoms at all
Treatment for VT
- ICD (Implantable Cardioverter Defibrillator): For patients at high risk of life-threatening VT or ventricular fibrillation, an ICD provides automatic protection — detecting dangerous rhythms and delivering a life-saving shock when needed.
- Catheter ablation for VT: VT ablation is one of the most complex procedures in electrophysiology. It involves detailed 3D electroanatomical mapping of the ventricle to identify and eliminate the circuits responsible for VT. It is highly effective at reducing VT burden, improving quality of life, and reducing ICD shocks.
- Antiarrhythmic medications: Drugs such as amiodarone, mexiletine, or sotalol can suppress VT episodes, often used alongside an ICD or following ablation.
Dr. Luni has extensive experience in both PVC ablation and complex VT ablation, including cases requiring mechanical circulatory support. If you have been told you have frequent PVCs or have experienced episodes of ventricular tachycardia, an EP evaluation is the right next step.