Patient Education
Arrhythmia

What is an Arrhythmia?

Heart failure impairs both the heart muscle and the heart's electrical system. Disturbances of the heart's normal rhythm, which can manifest as arrhythmias - result from problems with the electrical system. Because of heart muscle damage, patients with heart failure commonly have arrhythmias, especially from the lower chambers of the heart (the ventricles) consisting of slow, fast, or irregular heart beats.

Management of arrhythmias in heart failure patients is a specialized field and requires the collaboration between arrhythmia and heart failure specialists. Some of the drugs made to suppress these rhythm disturbances can also decrease the heart's pumping ability, which could worsen heart failure and in turn cause more arrhythmias. The goal of therapy is to treat the arrhythmia and the heart failure together.

Extra or rapid heart beats, called palpitations, are sometimes felt as "fluttering sensations" in the chest. Some people faint or feel dizzy or short of breath. Still others may feel chest pain or nothing at all when they have an arrhythmia. Generally, but not always, the longer the arrhythmia lasts, the more severe the symptoms.

Arrhythmias are divided into two main types, bradycardia (slow heart rates) and tachycardia (fast heart rates).

Bradycardia

A type of arrhythmia (abnormal heart rhythm) where the resting heart rate is slower than normal, or below 60 beats per minute. This is caused by the disruption of electrical signals that normally keep the heart beating at a steady pace.

A normal heart rate is between 60-100 beats per minute. The resting heart rate during sleep, and that of some athletes, sometimes falls below 60 beats per minute, but is not often considered abnormal.

During bradycardia, the heart rate is so slow that not enough blood is pumped throughout the body. This can result in fainting, dizziness, shortness of breath, or fatigue.

Tachycardia

A type of arrhythmia (abnormal heart rhythm) where the resting heart rate is faster than normal, or above 100 beats per minute.

During exercise or stress, the heart rate can rise above 100 beats per minute, but this is normal. Tachycardia that occurs when a person is at rest, and depending on the health status of the patient, may be harmful or life threatening.

Tachycardia may cause the heart to pump an insufficient amount of blood throughout the body, causing fainting, dizziness, shortness of breath, or fatigue.

Both bradycardia and tachycardia can be especially dangerous to someone with heart failure and a weakened heart muscle (cardiomyopathy). When the heart beats too slowly, too little blood is pumped out to the rest of the body. When the heart beats too quickly, it cannot fill completely so the body does not receive the blood volume it needs to function properly.

Arrhythmias are often diagnosed by cardiac exam, electrocardiogram (ECG), Holter monitor, event recorder, or an invasive examination of the heart called an electrophysiology study. After thoroughly examining you and determining that you do have an arrhythmia or are at high risk to develop one, the doctor may order one or more tests to determine the type of arrhythmia present, what may have caused it, and how to treat it.