Causes of High Heart Rate (Tachycardia)

Introduction

A high heart rate, medically known as tachycardia, occurs when the heart beats faster than 100 beats per minute (bpm) at rest. This condition can be temporary due to lifestyle factors or a sign of an underlying health problem. Understanding the causes can help in managing or preventing complications.

Common Causes of High Heart Rate

1. Physiological (Normal) Causes

Sometimes, an increased heart rate is a natural response to certain conditions, including: - Exercise – Physical exertion causes the heart to pump faster to deliver oxygen to muscles. - Stress and Anxiety – Emotional distress triggers the release of adrenaline, which accelerates heart rate. - Fever – When body temperature rises, the heart beats faster in response. - Dehydration – Reduced blood volume forces the heart to work harder to maintain circulation. - Caffeine and Stimulants – Substances like coffee, nicotine, or energy drinks can elevate heart rate.

2. Medical Conditions Leading to High Heart Rate

Certain health issues can cause sustained tachycardia, including:

A. Cardiovascular Causes:

• Arrhythmias – Irregular heart rhythms, such as atrial fibrillation or supraventricular tachycardia (SVT), can elevate heart rate.
• High Blood Pressure (Hypertension) – The heart compensates by beating faster to circulate blood more effectively.

• Heart Failure – In weakened heart function, the heart may beat faster to meet the body's oxygen needs.

  B. Non-Cardiac Causes:

• Thyroid Disorders – Overactive thyroid (hyperthyroidism) increases heart rate.

• Anemia – Low red blood cell count reduces oxygen supply, requiring the heart to work harder.
• Infections and Sepsis – Severe infections can trigger a systemic response, elevating heart rate.
• Lung Diseases (COPD, Asthma) – Poor oxygen exchange makes the heart pump more frequently.

3. Medications and Substance Use

Some drugs can cause tachycardia as a side effect: - Decongestants and Cold Medicines (contain stimulants like pseudoephedrine). - Asthma medications (beta-agonists like albuterol can temporarily increase heart rate). - Illegal drugs (cocaine, methamphetamine) – Strong stimulants that cause dangerous tachycardia.

When to See a Doctor?

Seek medical attention if tachycardia is accompanied by: - Chest pain - Dizziness or fainting - Shortness of breath - Palpitations or irregular heartbeats

If you experience persistent or unexplained tachycardia, consult a doctor to determine the underlying cause and receive appropriate treatment.

Source recommendations

1. American College of Cardiology/American Heart Association Guidelines on Supraventricular Tachycardia

1. https://www.ahajournals.org/doi/10.1161/CIR.0000000000001193
2. https://www.acc.org/Guidelines
3. https://www.ahajournals.org/doi/10.1161/cir.0000000000000311
4. https://www.acc.org/Latest-in-Cardiology/ten-points-to-remember/2015/09/23/09/13/2015-ACC-AHA-HRS-Guideline-for-the-Management-of-Adult-Patients-With-SVT
5. https://pubmed.ncbi.nlm.nih.gov/26399662/

2. European Society of Cardiology Guidelines on Heart Rhythm Disorders

1. https://www.escardio.org/
2. https://www.hrsonline.org/guidance/clinical-resources
3. https://www.escardio.org/Sub-specialty-communities/European-Heart-Rhythm-Association-(EHRA)
4. https://www.heartrhythmjournal.com/article/S1547-5271(23)02246-4/fulltext
5. https://www.escardio.org/The-ESC/Press-Office/Press-releases/EHRA-2022-cutting-edge-science-in-heart-rhythm-disorders