One change that occurs with aging is that the heart’s electrical system, which keeps the heartbeat regular, can degrade.

A healthy heart beats between 60 and 80 times a minute. (The average rate is 72 beats per minute). Any significant deviation from that range is called an arrhythmia, or heartbeat irregularity.

The likelihood of developing such an arrhythmia increases with age.

Your heart’s electrical system is made up of tiny nerves, each of which is wrapped in a protective layer of fat and very small blood vessels, often the size of a single cell.

With time, these small vessels can become clogged, and the heart’s electrical system can begin to misfire, much like frayed lamp wiring can short-circuit. This can result in arrhythmia.

The most common type of heartbeat irregularity that occurs with aging is atrial fibrillation, which causes the upper chambers of the heart to beat 300 to 600 times per minute. The beats become so chaotic that many do not reach the ventricle, which then fails to pump enough blood.

There are many causes of atrial fibrillation, including:

• High blood pressure

• Congestive heart failure

• Coronary artery disease

• Heart attack damage

• Diabetes

• Heart valve disease

However, the most common cause of atrial fibrillation is aging. Most cases occur in people over 60. The average age for atrial fibrillation is 66.8 years for men and 74.6 years for women.

Treatments for atrial fibrillation include medication; the implantation of a pacemaker (particularly in people who have tachy-brady syndrome, which is a combination of fibrillation and a too-slow heart rate response); or the implantation of a device called a low-energy internal atrial defibrillator (atrial ICDs).

An ICD is similar to a pacemaker, delivering a controlled electric shock to restore the heart’s normal rhythm if fibrillation begins.

There is also a newer procedure called catheter ablation, which uses bursts of radio frequency energy to destroy small areas of the heart muscle that are giving rise to abnormal electrical signals.