A pacemaker consists of a battery, a computerized generator, and wires with sensors at their tips. (The sensors are called electrodes.) The battery powers the generator, and both are surrounded by a thin metal box. The wires connect the generator to the heart.
A pacemaker helps monitor and control your heartbeat. The electrodes detect your heart's electrical activity and send data through the wires to the computer in the generator.
If your heart rhythm is abnormal, the computer will direct the generator to send electrical pulses to your heart. The pulses travel through the wires to reach your heart.
Newer pacemakers can monitor your blood temperature, breathing, and other factors. They also can adjust your heart rate to changes in your activity.
The pacemaker's computer also records your heart's electrical activity and heart rhythm. Your doctor will use these recordings to adjust your pacemaker so it works better for you.
Your doctor can program the pacemaker's computer with an external device. He or she doesn't have to use needles or have direct contact with the pacemaker.
Pacemakers have one to three wires that are each placed in different chambers of the heart.
The two main types of programming for pacemakers are demand pacing and rate-responsive pacing.
A demand pacemaker monitors your heart rhythm. It only sends electrical pulses to your heart if your heart is beating too slow or if it misses a beat.
A rate-responsive pacemaker will speed up or slow down your heart rate depending on how active you are. To do this, the device monitors your sinus node rate, breathing, blood temperature, and other factors to determine your activity level.
Your doctor will work with you to decide which type of pacemaker is best for you.
Clinical trials are research studies that explore whether a medical strategy, treatment, or device is safe and effective for humans.
August 19, 2014
Gary H. Gibbons
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