Tachycardia

What is Tachycardia?
Tachycardia (tak-ih-KAHR-dee-uh) is the medical term for a resting heart rate that is unusually fast—specifically, over 100 beats per minute (BPM) in adults.

Normal vs. Abnormal: It is entirely normal for your heart rate to increase significantly during physical exercise or acute stress as your body demands more oxygen. It is considered abnormal and potentially dangerous if your heart races while you are resting, sitting still, or sleeping.

Symptoms

When the heart beats too fast, it cannot fill up with enough blood between beats, meaning it cannot pump blood effectively to the rest of the body or the brain. You may experience:

• Palpitations: An uncomfortable racing, fluttering, pounding, or "flopping" sensation in the chest.
• Dizziness & Lightheadedness: Caused by a sudden drop in blood pressure and low oxygen reaching the brain.
• Shortness of Breath: Feeling easily winded or unable to catch your breath.
• Chest Pain: Uncomfortable pressure or tightness in the chest area.
• Syncope: Fainting or a temporary loss of consciousness.

Types of Tachycardia

[Image of the electrical conduction system of the human heart]

Type	Description	Severity
Atrial Fibrillation (AFib)	Chaotic, irregular electrical signals originating in the heart's upper chambers (atria).	Moderate (Significantly increases stroke risk).
SVT (Supraventricular)	An electrical "short circuit" above the lower chambers causes sudden, temporary bursts of a rapid heart rate.	Usually not life-threatening, but highly uncomfortable.
Ventricular Tachycardia (V-Tach)	Rapid, abnormal signals in the lower chambers (ventricles). The heart beats so fast it can't fill with blood.	High Emergency. Can be life-threatening.
Ventricular Fibrillation (V-Fib)	The lower chambers quiver uselessly instead of pumping blood.	Fatal within minutes without immediate CPR and Defibrillation.

⚠️ WHEN TO CALL 911
A racing heart can sometimes be a sign of a severe, life-threatening cardiovascular event. Seek emergency medical help immediately if your rapid heartbeat is accompanied by:

• Severe chest pain or pressure lasting more than a few minutes.
• Significant difficulty breathing or shortness of breath.
• Sudden weakness, paralysis, or fainting.

Causes & Triggers

Tachycardia is caused by something disrupting the normal electrical impulses that control the rate of your heart's pumping action. Common triggers include:

• Lifestyle Factors: High consumption of caffeine, alcohol abuse, or chronic smoking (nicotine acts as a powerful stimulant).
• Emotional Stress: Sudden fright, severe anxiety, or a panic attack.
• Medical Conditions: High blood pressure, an overactive thyroid gland (Hyperthyroidism), anemia, or a severe electrolyte imbalance (low potassium/magnesium).
• Substance Abuse: Recreational stimulants like cocaine or methamphetamines.

Diagnosis

To accurately diagnose the specific type of tachycardia, doctors use non-invasive tools to "catch" and record your heart's rhythm:

• ECG (Electrocardiogram): A quick test that records the electrical signals of your heart for a few seconds while you rest in a clinic.
• Holter Monitor: A small, portable ECG device worn continuously for 24 to 48 hours to record your heart activity during daily routines.
• Event Monitor: Similar to a Holter monitor but worn for up to a month; you press a button to record the rhythm only when you actively feel symptoms.

Treatment

Treatment aims to slow the heart rate down, prevent future episodes, and minimize the risk of complications like blood clots or strokes.

1. Vagal Maneuvers (Self-Care)

You can sometimes stop a sudden SVT episode on your own by physically stimulating the Vagus Nerve, which helps regulate your heartbeat:

• Coughing: Coughing forcefully and repeatedly.
• Bearing Down: Straining your abdominal muscles as if you are having a bowel movement (the Valsalva maneuver).
• Cold Water: Placing a frozen ice pack or splashing ice-cold water on your face for a few seconds.

2. Medical Procedures

• Cardioversion: A medical procedure where a controlled electric shock is delivered to the chest to instantly "reset" the heart's rhythm.
• Catheter Ablation: A minimally invasive procedure where energy (heat or cold) is used to destroy the tiny, specific cluster of heart tissue causing the electrical short circuit.
• Pacemaker / ICD: A small device surgically implanted under the skin that constantly monitors the heart and delivers precise electrical shocks to correct dangerous rhythms.

3. Medications

• Anti-arrhythmics & Beta Blockers: Daily prescription pills used to slow the heart rate and prevent rapid firing.
• Blood Thinners: (Like Warfarin or Eliquis) Frequently prescribed for patients with AFib to prevent blood from pooling and forming dangerous clots that could cause a stroke.

Frequently Asked Questions (FAQs)

Is a resting heart rate of 95 BPM considered tachycardia?

No. For a healthy adult, a normal resting heart rate sits anywhere between 60 and 100 beats per minute. Tachycardia is clinically defined as a resting heart rate consistently above 100 BPM. However, if you normally rest at 60 BPM and suddenly jump to 95 BPM with accompanying dizziness, you should consult a doctor.

Can a panic attack cause tachycardia?

Yes. A panic attack or severe anxiety causes an intense surge of adrenaline in the body. This "fight or flight" response naturally causes the heart to beat much faster and harder. While a panic-induced rapid heart rate can feel terrifying and mimic a heart condition, the rhythm itself is typically a normal sinus rhythm, just accelerated.

References

• American Heart Association (AHA) - Tachycardia
• Mayo Clinic - Tachycardia Overview
• National Heart, Lung, and Blood Institute (NHLBI) - Arrhythmia