The normal heart rate varies from person to person but generally ranges between 60-100 beats per minute at rest. When the heart rate exceeds 100 beats per minute, it is considered tachycardia. (1)

In this article, we will explore the various causes of rapid heartbeat without exertion, how to manage it, and when to seek medical advice.

Causes of Rapid Heartbeat Without Exertion

The causes of tachycardia (fast heartbeat) can be categorized into two main types: (2)(3)

1. Temporary or Non-Serious Causes

Not all cases of tachycardia are dangerous. Many everyday situations unrelated to heart disease can cause a temporary increase in heart rate, such as:

  • Anxiety, stress, and fear – Emotional stress increases stress hormone levels, stimulating the heart to pump faster.
  • Caffeine and nicotine – Found in coffee, tea, soft drinks, tobacco, and smoking products, these stimulate the nervous system, leading to a temporary increase in heart rate.
  • Fever (high body temperature) – Fevers caused by infections and inflammation can lead to an increased heart rate as part of the body’s natural response.
  • Certain medications – Drugs such as asthma medications, cold and flu treatments, and thyroid medications may cause an elevated heart rate as a side effect.
  • Low blood sugar or low blood pressure – Tachycardia is a common symptom in both hypoglycemia (low blood sugar) and hypotension (low blood pressure).
  • Hormonal changes during pregnancy and childbirth – The hormonal fluctuations during pregnancy and delivery can influence heart rate.
  • Prolonged standing – Standing for long periods may cause blood pooling in the legs, reducing the amount of blood returning to the heart, which compensates by beating faster.
  • Obesity – Excess weight puts additional strain on the heart, leading to an increased heart rate.
  • Alcohol and drug use – Alcohol and certain recreational drugs can trigger an increased heart rate.


2. Underlying Medical Conditions

In some cases, tachycardia may indicate a more serious health issue, including: (4)

  • Anemia – A lack of red blood cells results in reduced oxygen levels, causing the heart to pump faster to compensate.
  • Heart diseases, such as:

* Cardiac arrhythmias (irregular heartbeats).

* Coronary artery disease (reduced blood flow to the heart).

* Heart attack (myocardial infarction).

* Cardiomyopathy (weakening of the heart muscle).

* Heart valve diseases.

* Congenital heart defects.

* Heart tumors.

* Myocarditis (heart muscle inflammation).


  • Lung diseases, such as asthma – Shortness of breath forces the heart to work harder to supply oxygen-rich blood to the body.
  • Hyperthyroidism (overactive thyroid gland) – Excess thyroid hormones increase metabolic rate, causing the heart to beat faster.
  • Other causes, including:

* Cushing’s syndrome and adrenal gland tumors.

* Electrolyte imbalances (abnormal levels of sodium, potassium, calcium, and magnesium).

When Should You See a Doctor?

Medical attention is required if tachycardia persists, worsens, or occurs in individuals with a history of heart disease. Additionally, seek immediate medical help if rapid heartbeats are accompanied by: (5)

  • Chest pain.
  • Shortness of breath.
  • Dizziness or fainting.
  • Swelling in the legs or feet.
  • Persistent or severe palpitations.




💙 Experiencing a rapid heartbeat without physical exertion? Don’t ignore it! Book an appointment today at Al-Ahli Hospital’s Heart Care Center for a comprehensive consultation and accurate diagnosis.



Diagnosing the Causes of Rapid Heartbeat

To determine the cause of tachycardia, the doctor will: (5)

✔ Review your medical and family history.

✔ Perform a physical examination.

✔ Order diagnostic tests, which may include:

  • Electrocardiogram (ECG) – Measures the electrical activity of the heart.
  • Stress test – Evaluates heart function during exercise.
  • Echocardiogram (Echo) – Uses ultrasound imaging to assess heart structure and blood flow.
  • Blood tests – Checks electrolyte levels and thyroid function.


References

  • Inappropriate Sinus Tachycardia Symptoms and Treatment, Very Well Health
  • Why Is My Heart Beating So Fast?, University of Utah Health
  • Tachycardia: Fast Heart Rate, American Heart Association
  • Why Is My Heart Beating So Fast? 19 Causes, Normal Heart Rates Chart, eMedicineHealth.com
  • What Is a Dangerous Heart Rate?, Very Well Health