Supraventricular Tachycardia and Ventricular Tachycardia: Understanding the Conditions

Introduction

Heart rhythm disturbances, known as arrhythmias, can arise from different areas of the heart. Two major classifications of fast heart rhythms are supraventricular tachycardia (SVT) and ventricular tachycardia (VT). Understanding these conditions is crucial for early diagnosis and management.

Supraventricular Tachycardia (SVT)

What is SVT?

SVT is a rapid heartbeat originating above the ventricles, usually in the atria or the AV node.

Causes of SVT:

• Reentrant electrical circuits in the atria
• Excessive activation of pacemaker cells
• Certain congenital heart conditions

Symptoms of SVT:

• Rapid heartbeat (palpitations)
• Dizziness or fainting
• Shortness of breath
• Chest discomfort

Diagnosis of SVT:

• Electrocardiogram (ECG) to detect abnormal heart rhythms
• Holter monitoring for continuous heart rhythm tracking
• Electrophysiological study (EPS) to examine electrical conduction in the heart

Treatment of SVT:

• Vagal maneuvers (such as the Valsalva maneuver) to slow heart rate
• Medications (beta-blockers, calcium channel blockers, or antiarrhythmics)
• Catheter ablation to destroy abnormal electrical pathways

Ventricular Tachycardia (VT)

What is VT?

VT is a fast heart rhythm originating in the ventricles, which can be life-threatening if sustained.

Causes of VT:

• Coronary artery disease and prior heart attacks (myocardial infarction)
• Heart failure
• Electrolyte imbalances (such as low potassium or magnesium)

Symptoms of VT:

• Palpitations
• Loss of consciousness
• Severe chest pain
• Cardiac arrest in extreme cases

Diagnosis of VT:

• ECG to differentiate from other tachycardias
• Echocardiography to evaluate structural heart disease
• Cardiac MRI for further assessment of heart tissue

Treatment of VT:

• Immediate stabilization with defibrillation in emergency cases
• Antiarrhythmic medications (amiodarone, lidocaine)
• Implantable cardioverter-defibrillator (ICD) for patients at high risk
• Catheter ablation to remove arrhythmic sites

Key Differences Between SVT and VT

• Origin: SVT starts in the atria or AV node, while VT originates in the ventricles.
• Severity: VT is more dangerous and can lead to sudden cardiac arrest.
• Treatment Approach: Both may require medications or ablation, but VT often necessitates an ICD.

Conclusion

Recognizing the symptoms and differences between SVT and VT is essential for proper management. If you experience recurrent palpitations, dizziness, or fainting spells, seek medical evaluation promptly.

Source recommendations

1. American Heart Association Guidelines on Supraventricular Tachycardia

1. https://www.ahajournals.org/doi/10.1161/cir.0000000000000311
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://professional.heart.org/en/science-news/guideline-for-the-management-of-adult-patients-with-supraventricular-tachycardia
5. https://pubmed.ncbi.nlm.nih.gov/26399662/

2. European Society of Cardiology Guidelines on Ventricular Arrhythmias

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