Tachycardia Symptoms: Racing Heart, Causes & Diagnosis

Quick Glance: Common Tachycardia Symptoms

Listed below are some of the common early symptoms of tachycardia:

A rapid heartbeat (palpitations)
A noticeably fast pulse
Shortness of breath
Light-headedness or dizziness
Weakness or unusual tiredness
Sweating
Chest discomfort or pressure
Feeling faint or briefly losing consciousness

Tachycardia Symptoms That Should Not Be Ignored

Tachycardia symptoms should not be ignored as they can progress and cause heart-related problems. Some of these symptoms and what they indicate are given in the table below:

Symptom	What It May Indicate
A fast heartbeat that begins and ends suddenly	A rhythm disorder such as supraventricular tachycardia
A persistently fast resting pulse	Infection, dehydration, anaemia, thyroid disease or an ongoing arrhythmia
Chest pain or pressure	Reduced blood flow to the heart or strain on the heart muscle
Shortness of breath, especially at rest	Reduced pumping efficiency or developing heart failure
Severe dizziness or near-fainting	Reduced blood flow to the brain
Fainting or collapse	A potentially serious rhythm disturbance, including ventricular tachycardia
A fast and irregular pulse	An atrial rhythm disorder that requires an ECG for confirmation
Increasing fatigue and reduced exercise tolerance	Persistent tachycardia or an underlying heart or systemic condition

Why Do Tachycardia Symptoms Occur?

Tachycardia occurs when the heart’s electrical system makes it beat faster than normal. A normal resting heart rate is usually 60 - 100 beats per minute (bpm) in adults. In case of tachycardia, the heart rate is more than 100 bpm while at rest.

When the heart beats too quickly, the ventricles (the lower pumping chambers) may not have enough time to fill with blood. This can reduce blood flow and oxygen to the brain and other organs, causing palpitations, dizziness, weakness, breathlessness or fainting.

Tachycardia Symptoms That Require Immediate Medical Attention

People should get immediate medical care at the nearest hospital if a fast heartbeat occurs with:

Chest pain, pressure or tightness
Severe shortness of breath
Fainting, collapse or loss of consciousness
Severe dizziness, confusion or difficulty staying awake
Sudden weakness, facial drooping or unclear speech
Cold, clammy skin with severe weakness
A seizure
A prolonged rapid heartbeat in someone with known heart disease
No detectable pulse or normal breathing

Symptoms of Tachycardia Based on Type

A brief overview of the symptoms based on the type of tachycardia is given below:

Type of Tachycardia	Common Symptoms
Sinus Tachycardia	Gradual increase in heart rate, pounding pulse, sweating, breathlessness and weakness; may occur with fever, exercise, pain, dehydration or anxiety
Supraventricular Tachycardia	Sudden, very rapid and usually regular heartbeat, chest fluttering, pounding sensation in the neck, dizziness, breathlessness, weakness or chest discomfort
Atrial Tachycardia	Rapid heartbeat, palpitations, tiredness, dizziness, reduced ability to exercise and shortness of breath
Ventricular Tachycardia	Rapid heartbeat, chest pain, severe dizziness, breathlessness, near-fainting, fainting or collapse

Symptoms of Tachycardia-Specific Conditions

A comparative overview of symptoms of tachycardia-specific conditions is given in the table below:

Tachycardia-Specific Condition	Common Symptoms
Inappropriate Sinus Tachycardia	Persistently or repeatedly fast resting heartbeat without a clear trigger, palpitations, tiredness, breathlessness, dizziness and reduced exercise tolerance
Postural Orthostatic Tachycardia Syndrome (POTS)	Rapid increase in heart rate after standing, dizziness or light-headedness, palpitations, shaking or sweating, blurred vision, weakness, fatigue or near-fainting
Paroxysmal Supraventricular Tachycardia (PSVT)	Episodes that begin and end suddenly, rapid and usually regular pulse, chest fluttering or pounding, dizziness, breathlessness and weakness
Tachycardia-Induced Cardiomyopathy	Persistent fast heartbeat, progressive tiredness, breathlessness, swelling in the feet or ankles, reduced ability to exercise and signs of reduced heart-pumping ability

Tachycardia Symptoms in Children

Older children may describe a racing or fluttering heartbeat, dizziness, chest discomfort, breathlessness or feeling faint, which may be symptoms of tachycardia. They may also become unusually tired during play or exercise.

Babies and younger children may not be able to describe palpitations. Warning signs of tachycardia can include:

Rapid breathing
Poor feeding
Unusual sweating
Pale or greyish skin
Irritability or restlessness
Extreme tiredness
Vomiting
A very rapid heartbeat felt through the chest

A prolonged rapid heartbeat, breathing difficulty, poor feeding, bluish discolouration or reduced responsiveness requires urgent paediatric assessment. Normal heart rates vary considerably by age, so adult heart-rate limits should not be used for children.

Can You Have Tachycardia Without Symptoms?

Yes. Some episodes are discovered during a routine pulse check, electrocardiogram or health examination. Short episodes may end or subside before the person notices any change.

Sinus tachycardia may also occur without obvious palpitations when it develops gradually due to fever, anaemia, dehydration, or another underlying condition. However, an unexplained fast resting heart rate should still be medically evaluated.

When Can Tachycardia Symptoms Become Life-Threatening?

Since tachycardia is a heart-related condition, its symptoms should not be ignored to ensure patient safety and health. However, some symptoms require medical attention at the earliest for prompt treatment.

The table below lists such tachycardia symptoms and also briefly elaborates why they should be treated as an emergency:

Emergency Condition	Why It Is Serious
Unstable Ventricular Tachycardia	The lower heart chambers may beat too quickly to pump enough blood, causing fainting, shock or cardiac arrest.
Cardiac Arrest	The heart stops pumping blood effectively, leading to unconsciousness, absent normal breathing and no detectable pulse.
Circulatory Shock	Severely reduced blood flow can cause confusion, cold clammy skin, weakness and very low blood pressure.
Acute Heart Failure	A prolonged rapid rhythm may cause severe breathlessness, low oxygen levels or fluid accumulation in the lungs.
Severe Underlying Illness	Sepsis, major blood loss, severe dehydration or an extreme thyroid disturbance may produce dangerous tachycardia and organ dysfunction.
Tachycardia-Induced Cardiomyopathy	A persistently fast rhythm can gradually weaken the heart muscle and reduce its pumping capacity.

How are Tachycardia Symptoms Diagnosed?

A cardiologist can examine medical history and conduct multiple tests to get conclusive evidence for a confirmed diagnosis of tachycardia. An overview of the diagnostic tests and their purpose is given below:

Diagnostic Test	Purpose
Pulse and Blood Pressure Measurement	Checks the heart rate, rhythm and effect on blood circulation.
12-Lead ECG	Records the heart’s electrical activity and identifies the rhythm producing tachycardia.
Holter Monitoring	Records the heartbeat continuously, usually for 24 hours or longer, to detect intermittent episodes.
Event Monitor or Loop Recorder	Records less frequent episodes over a longer period.
Complete Blood Count	Checks for anaemia or signs of infection.
Thyroid Function Tests	Look for an overactive thyroid as a possible cause of a fast heartbeat.
Electrolyte and Blood Glucose Tests	Check for chemical or metabolic disturbances affecting the heart rhythm.
Echocardiogram	Examines the heart’s structure, valves and pumping function.
Exercise Stress Test	Assesses symptoms or rhythm changes during physical activity.
Tilt-Table Test	Evaluates tachycardia and dizziness linked to standing or changes in blood pressure.
Electrophysiology Study	Maps the heart’s electrical pathways when the exact rhythm remains uncertain or a procedure is being considered.

FAQs

Q1. What is usually the first symptom of tachycardia?

Ans: The first noticeable symptom of tachycardia is often a racing, pounding or fluttering heartbeat. Some people first experience dizziness, weakness, breathlessness or reduced exercise tolerance instead.
Q2. Does a heart rate above 100 always mean a heart problem?

Ans: No. In adults, a resting heart rate above 100 beats per minute is medically termed as tachycardia. However, exercise, stress, fever, pain or dehydration can cause a temporary normal increase. A persistent or unexplained fast resting pulse needs evaluation.
Q3. Can tachycardia develop without palpitations?

Ans: Yes, tachycardia can develop without palpitations. Some people do not feel their heartbeat and may only notice tiredness, dizziness, breathlessness or reduced exercise capacity. An episode may also be found incidentally during an ECG.
Q4. When should I see a doctor for a fast heartbeat?

Ans: Consult a cardiologist when tachycardia episodes recur, occur during resting, last longer than usual or cause dizziness, weakness, breathlessness or difficulty performing normal activities. A first unexplained episode should also be assessed.
Q5. Can anxiety cause tachycardia?

Ans: Yes. Anxiety and panic can activate the body’s stress response and increase the heart rate, causing tachycardia. However, recurrent palpitations should not automatically be attributed to anxiety without checking for cardiac and medical causes.
Q6. Are tachycardia symptoms different in men and women?

Ans: The main symptoms of tachycardia in men and women are similar. Individual differences are usually related to the type of rhythm, age, pregnancy, anaemia, thyroid health and existing heart conditions rather than gender alone.
Q7. Can children develop tachycardia?

Ans: Yes. Children may have palpitations, dizziness, rapid breathing, poor feeding, sweating, or unusual tiredness, all of which are symptoms of tachycardia. A paediatrician should assess suspected episodes.
Q8. Which tachycardia symptoms indicate an emergency?

Ans: Chest pain, severe breathlessness, fainting, confusion, seizures, collapse or a fast heartbeat with abnormal breathing are some of the indicators of tachycardia. It is recommended to get immediate emergency care if you experience these symptoms.

References
- https://www.heart.org/en/health-topics/arrhythmia/about-arrhythmia/tachycardia--fast-heart-rate
- https://www.nhs.uk/conditions/supraventricular-tachycardia-svt/
- https://www.maxhealthcare.in/our-specialities/cardiology/conditions-treatments/supraventricular-tachycardia
- https://www.mayoclinic.org/diseases-conditions/tachycardia/symptoms-causes/syc-20355127
- https://my.clevelandclinic.org/health/diseases/22108-tachycardia