Tachycardia

What is Tachycardia?

Tachycardia refers to an abnormally fast heart rate, typically above 100 beats per minute (BPM) in adults. It can occur in both healthy individuals and those with underlying heart conditions. While some cases are harmless, others may increase the risk of stroke, heart failure, or cardiac arrest.

Types of Tachycardia

There are several types of tachycardia, classified based on their origin in the heart:

1. Supraventricular Tachycardia (SVT)

A rapid heartbeat originating above the ventricles. It includes conditions such as:

• Atrial Tachycardia - Irregular rapid heartbeat starting in the atria.
• Atrioventricular Nodal Reentrant Tachycardia (AVNRT) - Electrical misfiring in the AV node causes rapid heartbeats.
• Wolff-Parkinson-White Syndrome (WPW) - An extra electrical pathway leads to a fast and irregular heartbeat.

2. Ventricular Tachycardia (VT)

Originates in the ventricles and can be life-threatening, especially if sustained for long periods. It is often linked to heart disease, previous heart attacks, or electrolyte imbalances.

3. Sinus Tachycardia

Occurs when the heart's natural pacemaker (SA node) signals the heart to beat faster due to fever, stress, anemia, dehydration, or overuse of stimulants.

Causes and Risk Factors

Tachycardia can be triggered by several factors, including:

• High Blood Pressure (Hypertension)
• Heart disease (e.g., coronary artery disease, heart valve disorders)
• Electrolyte imbalances (e.g., low potassium or magnesium)
• Hyperthyroidism (overactive thyroid)
• Severe anemia
• Stress and anxiety
• Use of stimulants (caffeine, nicotine, alcohol, illicit drugs)
• Fever and infections

Symptoms of Tachycardia

Symptoms vary depending on the severity and duration of the condition but may include:

• Rapid or irregular heartbeat (palpitations)
• Shortness of breath
• Dizziness or lightheadedness
• Chest pain or tightness
• Fainting or near-fainting episodes (syncope)
• Extreme fatigue or weakness

When to Seek Medical Attention

Seek immediate medical help if you experience:

• Sudden onset of rapid heart rate (above 150 BPM).
• Severe chest pain or difficulty breathing.
• Loss of consciousness or fainting.
• Irregular heartbeats lasting more than a few minutes.

These symptoms may indicate a medical emergency, such as ventricular tachycardia or atrial fibrillation, which require urgent intervention.

Diagnosis of Tachycardia

Doctors may use various tests to diagnose the underlying cause of tachycardia:

• Electrocardiogram (ECG/EKG): Measures the heart's electrical activity.
• Holter Monitor: A portable ECG worn for 24-48 hours to track heart rhythms.
• Electrophysiology Study (EPS): Tests electrical pathways in the heart.
• Blood Tests: Checks for thyroid function, anemia, or electrolyte imbalances.

Treatment and Management

Treatment for tachycardia depends on its severity and underlying cause. Options include:

• Vagal Maneuvers: Techniques such as deep breathing or bearing down to slow the heart rate.
• Medications: Beta-blockers or antiarrhythmic drugs to regulate heart rhythm.
• Cardioversion: Electrical shock therapy to reset heart rhythm.
• Catheter Ablation: A procedure to destroy abnormal heart tissue causing irregular rhythms.
• Pacemaker or Implantable Cardioverter Defibrillator (ICD): Used in life-threatening cases.