Non-Sustained Ventricular Tachycardia (NSVT)

1. Introduction

Non-Sustained Ventricular Tachycardia (NSVT) is an arrhythmia originating in the ventricles of the heart, characterized by rapid heartbeats that last for less than 30 seconds and terminate spontaneously. It is often detected on Holter monitoring or ECG during routine examinations.

2. Causes and Risk Factors

NSVT can occur in healthy individuals but is more commonly associated with underlying heart conditions such as: - Coronary artery disease (CAD) — Reduced blood flow to the heart can trigger arrhythmias. - Heart failure — Structural heart disease increases the risk of ventricular arrhythmias. - Hypertrophic cardiomyopathy (HCM) — A genetic heart disease that predisposes to arrhythmias. - Electrolyte imbalances — Low potassium or magnesium levels can contribute to arrhythmias. - Use of stimulant drugs — Such as caffeine, nicotine, or illicit drugs.

3. Symptoms and Clinical Significance

Many people with NSVT do not experience noticeable symptoms, but some may feel: - Palpitations (a sensation of rapid or irregular heartbeats) - Dizziness or lightheadedness - Shortness of breath - Chest discomfort In some cases, NSVT can increase the risk of sudden cardiac arrest, especially in individuals with underlying heart disease.

4. Diagnosis

Common tests to diagnose NSVT include: - Electrocardiogram (ECG) — A resting ECG may capture NSVT if the event occurs during testing. - Holter monitor or event recorder — These devices record heart rhythms over 24–48 hours and can detect intermittent NSVT episodes. - Echocardiogram — Identifies structural heart disease. - Cardiac MRI or stress testing — Used in cases where further investigation is needed.

5. Treatment Strategies

Treatment for NSVT depends on the underlying cause and presence of symptoms: - No treatment: If NSVT occurs in a healthy heart and without symptoms, no intervention may be needed. - Medications: Beta-blockers or antiarrhythmic drugs may be used to suppress arrhythmia. - Catheter ablation: In patients with frequent symptomatic NSVT, a procedure to destroy the abnormal heart tissue causing the arrhythmia may be considered. - Implantable cardioverter-defibrillator (ICD): If NSVT occurs in patients with significant heart disease and a high risk of sudden cardiac death, an ICD may be recommended.

6. Conclusion

While NSVT is not always dangerous, it can be an indicator of more serious cardiac issues, depending on the patient’s overall heart health. Regular monitoring and appropriate management can help reduce risks and improve quality of life.

Source recommendations

1. American Heart Association Guidelines for Ventricular Arrhythmias

1. https://www.ahajournals.org/doi/10.1161/CIR.0000000000000549
2. https://www.heart.org/en/health-topics/arrhythmia/about-arrhythmia/tachycardia--fast-heart-rate
3. https://www.ahajournals.org/doi/10.1161/CIR.0000000000001193
4. https://cpr.heart.org/en/resuscitation-science/cpr-and-ecc-guidelines/algorithms
5. https://www.heart.org/en/health-topics/arrhythmia/about-arrhythmia/ventricular-fibrillation

2. European Society of Cardiology Guidelines for Ventricular Arrhythmias and Sudden Cardiac Death

1. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines/Ventricular-Arrhythmias-and-the-Prevention-of-Sudden-Cardiac-Death
2. https://academic.oup.com/eurheartj/article/43/40/3997/6675633
3. https://www.ahajournals.org/doi/10.1161/CIR.0000000000000549
4. https://pubmed.ncbi.nlm.nih.gov/36017572/
5. https://www.sciencedirect.com/science/article/pii/S2405500X22010945