Cardiac Arrhythmia

Overview

Cardiac arrhythmias, also known as heart arrhythmias, are conditions characterized by abnormal heart rhythms. These can occur when the electrical impulses that coordinate heartbeats do not function properly, causing the heart to beat too fast (tachycardia), too slow (bradycardia), or irregularly. This can disrupt the flow of blood to the body, leading to potentially serious complications such as heart failure, stroke, or sudden cardiac death.

A close-up image of a heart with visible electrical impulses.

Types of Cardiac Arrhythmias

There are several types of cardiac arrhythmias, each with its own set of symptoms, causes, and treatment options. The most common types include:

Atrial Fibrillation (AF): This is the most common type of serious arrhythmia. It occurs when rapid, disorganized electrical signals cause the atria, the heart's upper chambers, to fibrillate, or contract rapidly and irregularly.

Atrial Flutter: This is similar to AF but the rhythm in your atria is more organized and less chaotic than the abnormal patterns caused by atrial fibrillation.

Supraventricular Tachycardia (SVT): This includes a few types of arrhythmias, such as atrial fibrillation, atrial flutter, and paroxysmal supraventricular tachycardia.

Ventricular Tachycardia: This is a rapid, regular heart rate that originates with abnormal electrical signals in the ventricles.

Ventricular Fibrillation: This is an emergency situation in which the heart's lower chambers quiver and the heart cannot pump any blood, causing cardiac arrest.

Causes of Cardiac Arrhythmias

Cardiac arrhythmias can be caused by several factors, including:

Heart Disease: This is the most common cause of cardiac arrhythmias. Other heart-related conditions can also increase the risk, including high blood pressure, congestive heart failure, and atherosclerosis.

Electrolyte Imbalance: Minerals in your blood like sodium, potassium, calcium, and magnesium help trigger and conduct the electrical impulses in your heart. Electrolyte levels that are too high or too low can affect your heart's electrical impulses and contribute to arrhythmia development.

Heart Attack or a healing process after heart surgery.

Certain genetic factors can also contribute to the development of cardiac arrhythmias.

Symptoms of Cardiac Arrhythmias

Symptoms of cardiac arrhythmias can vary greatly depending on the type and severity of the arrhythmia. Some people with cardiac arrhythmias have no symptoms at all. However, when symptoms do occur, they may include:

Palpitations (a feeling of skipped heart beats, fluttering or "flip-flops," or feeling that your heart is "running away").
Pounding in your chest.
Dizziness or feeling light-headed.
Fainting (syncope).
Shortness of breath.
Chest discomfort or pain.
Fatigue (feeling overly tired or weak).
Confusion or difficulty concentrating.

Diagnosis of Cardiac Arrhythmias

Diagnosis of cardiac arrhythmias typically involves a combination of physical examination, medical history, and diagnostic tests. These may include:

Electrocardiogram (ECG): This is the most common test for diagnosing arrhythmias. It records the electrical activity of the heart and can help identify the type and location of the arrhythmia.

Holter Monitor: This is a portable ECG device that can be worn for a day or more to record the heart's activity throughout the day.

Event Monitor: This is a portable ECG device that monitors your heart's activity for a few weeks or months.

Echocardiogram: This test uses sound waves to create detailed images of the heart's structure and function.

Cardiac Catheterization: This test involves threading a thin tube (catheter) through a blood vessel to the heart to diagnose heart conditions and perform certain treatments.

Treatment of Cardiac Arrhythmias

Treatment for cardiac arrhythmias depends on the type and severity of the arrhythmia. Some arrhythmias may require no treatment at all, while others may require medication, lifestyle changes, or even surgery. Treatment options may include:

Antiarrhythmic Medications: These drugs control the heart rate and restore normal heart rhythm. They can be used to treat both fast and slow arrhythmias.

Pacemaker: This is a small device that's placed under the skin of your chest or abdomen to help control abnormal heart rhythms. It uses electrical pulses to prompt the heart to beat at a normal rate.

Implantable Cardioverter-Defibrillator (ICD): This is a small device that's implanted in your chest or abdomen and uses electrical shocks to control life-threatening arrhythmias.

Cardiac Ablation: This procedure uses radiofrequency energy (similar to microwave heat) to destroy a small area of heart tissue that's causing rapid and irregular heartbeats.

Cardioversion: This is a procedure that can restore a fast or irregular heartbeat to a normal rhythm. It's often done by sending electric shocks to your heart through electrodes placed on your chest.

Prevention of Cardiac Arrhythmias

Preventing cardiac arrhythmias involves managing known heart disease and adopting a heart-healthy lifestyle. This can include:

Eating a heart-healthy diet.
Regular exercise.
Quitting smoking.
Limiting caffeine and alcohol.
Reducing stress and practicing relaxation techniques.