Your heart has its own electrical system that, ideally, keeps it beating steadily throughout your life.

But aging, heart disease, and other cardiac problems can result in heartbeat irregularities. When that happens, a pacemaker can help by generating electrical impulses to regulate your heartbeat. A traditional pacemaker has two parts: leads and a pulse generator, which houses the battery. Leads are wires threaded through the veins to the heart that send the impulses from the pulse generator. A resting heart usually beats about 50 to 70 times a minute.

But if you’re exercising or under stress, it can increase to double or even triple that speed. On the other hand, if your heart beats too slowly — or irregularly — you may experience symptoms such as fainting, confusion, dizziness, fatigue, or shortness of breath.

As people age, they often find themselves growing tired. Many ignore the change, believing that it’s just a normal sign of aging. But the culprit may be a too-slow heartbeat — a condition called bradycardia. A pacemaker can correct such a condition.

Pacemakers are also used to correct tachycardias, arrhythmias in which the heart beats faster than normal (more than 100 beats per minute) while a person is at rest. Common types of tachycardia include atrial and ventricular fibrillation, and atrial flutter.

Other things a pacemaker can do include:

• Correct heart block, which occurs when the heart stops beating for a few to several seconds

• Coordinate electrical signaling between the upper and lower chambers of the heart

Pacemakers that coordinate signals between ventricles are called cardiac resynchronization therapy (CRT) devices. They are used to treat congestive heart failure