A pacemaker is a small, battery-powered device that helps the heart beat at a normal rate and rhythm. It is implanted under the skin near the collarbone or in the stomach area through a small incision on the chest. The device has two parts: a pulse generator and leads, which are wires that connect the heart to the generator and carry the electrical messages to the heart. There are different types of pacemakers, including:

• Single chamber pacemaker: This type usually sends electrical signals to the lower right chamber of the heart.
• Dual chamber pacemaker: This type sends electrical signals to the upper and lower right heart chambers.
• Biventricular pacemaker: This type also is called a cardiac resynchronization pacemaker. Its for people who have heart failure and a slow heartbeat. The device stimulates both lower heart chambers. It helps make the heart muscle stronger.

A pacemaker is used to control or increase the heartbeat. It stimulates the heart as needed to keep it beating regularly. A pacemaker only works when it senses trouble with the heartbeat. For example, if the heart beats too slowly, the pacemaker sends electrical signals to correct the beat. Some pacemakers can increase the heartbeat as needed, such as during exercise. A pacemaker may be recommended for people who have heart problems that cause their heart to beat too slowly, such as sinus node disease and heart block.

In summary, a pacemaker is a device that helps control an irregular heart rhythm by sending electrical pulses to the heart to keep it beating at a normal rate and rhythm. It is implanted under the skin and has two parts: a pulse generator and leads. There are different types of pacemakers, and they are used to control or increase the heartbeat as needed.