Normal heart beats are regular. They depend on electrical signals in the heart muscle. These signals cause the heart chambers to contract and pump blood throughout the body. The heart has two upper chambers (atria) and two lower chambers (ventricles). Arrhythmias can happen in either set of chambers.

A normal heart rate for older adults at rest is between 60 and 80 beats per minute. People in good physical shape or who take certain medications may have slower heart rates.

Feeling an irregular heartbeat (arrhythmia) occasionally is harmless. But only if the feeling is not accompanied by other concerning symptoms as chest discomfort or dizziness.

Types of Arrhythmias

There are different types of arrhythmias, including:

• Bradycardia is an abnormally slow heart rate.
• Tachycardia is an abnormally fast heart rate.
• Atrial arrhythmias come from the upper heart chambers (atria).
• Ventricular arrhythmias come from the lower heart chambers (ventricles).

Take irregular heartbeats seriously if you’ve had a heart attack or suffer from coronary artery disease or heart failure. A person needs to see a healthcare professional quickly if they have:

• History of irregular heart beats.
• Significant heart disease.
• Unusual heartbeats that keep coming back, do not go away, or last longer than a few minutes.
• Other symptoms (chest discomfort or pain, trouble breathing, lightheadedness, or dizziness) when the irregular heartbeats happen.

Atrial Fibrillation

Atrial fibrillation is the most common type of arrhythmia, especially in older adults. About 10 percent of people in their 80s have it.

Among older adults with valvular heart disease (related to valves that control blood flow in the heart) or heart failure, 30 percent have atrial fibrillation.

Strokes are related to atrial fibrillation and the risk rises with age. Atrial fibrillation is responsible for about 24 percent of strokes among people in their 80s.

Atrial fibrillation happens when the upper (atrial) chambers of the heart contract rapidly and irregularly (“fibrillates”). Atrial fibrillation may be continuous (all the time) or intermittent (meaning it comes and goes).

Atrial fibrillation can cause:

• A dangerous and rapid ventricular (lower chamber) heartbeat is called Atrial Fibrillation with Rapid Ventricular Rate (Afib with RVR). In this state, the heart cannot pump blood effectively causing symptoms such as shortness of breath, chest discomfort, dizziness, or lightheadedness.
• Blood flow to slow down and pool inside the heart. This can cause blood clots, which can travel to the brain, causing a stroke.  

Bradycardia

Bradycardia (slow heart rhythm) can result from:

• A normally slow heart rate during sleep.
• Medications, such as beta-blockers, calcium-channel blockers, and medications used to treat dementia.
• Problems with the heart’s electrical signals.

Most older adults with bradycardia do not have symptoms. However, some have symptoms such as fatigue, weakness, lightheadedness, dizziness, shortness of breath, fainting spells, or falls.  These symptoms should get emergency evaluation.

Ventricular Tachycardia/Ventricular Fibrillation

Ventricular arrhythmias, which come from the lower chambers of the heart, are less common but more serious. People with heart disease are more likely to have these types of arrhythmias.

Occasional premature, or “early” beats from the ventricles are common even in healthy people. If these early ventricular beats become frequent or continuous, they can become life-threatening. Early warning signs include:

• Chest pain
• Rapid heartbeat (palpitations)
• Dizziness
• Nausea

Because these arrhythmias do not allow the heart to pump effectively, blood stops circulating, and the person becomes unconscious. This is called “cardiac arrest.” 

Last Updated February 2023