My grandfather came home from the hospital recently and showed me the sutures on his chest. ��What happened?�� I asked him. He said that he had a pacemaker implanted. I had heard about a pacemaker before but did not really know how it worked, so I began to research about the device.

Essentially a pacemaker is a small electronic device is implanted under the skin in the chest area with wired electrodes attached to specific locations on the heart to regulate the heart��s rhythm. However I realized modern pacemakers have become much more sophisticated. Modern pacemakers are actually miniature computers that monitor the patient��s heartbeat to detect irregular rhythms. Once an irregular rhythm is detected, the pacemaker goes into action to bring the heart��s rhythm back into normal sinus rhythm.

The pacemaker also captures and stores a log of the heart��s rhythm, pattern, speed, and other useful data. Doctors can easily retrieve this data from the device using a wireless reader and therefore do not need to surgically remove or attach wires to the device. My grandfathers pacemaker can even connect to a Wi-Fi router to allow doctors to download data, see his heart condition in real-time, and even make setting adjustments remotely from their office via the Internet.

One additional function of his pacemaker is it doubles as a defibrillator. In other words, if his heart goes into cardiac arrest as in when he is having a heart attack. The device senses the condition and will initiate a life saving shock to restart the heart in an effort to reestablish a normal sinus rhythm. This is similar to what you��ve seen in hospital emergency rooms or paramedics using charged electric pads on a heart attack patient��s chest.

A new feature of my grandfather��s pacemaker is that it is MRI compliant. Normally no metal is allowed in a Magnetic Resonance Imaging scanner since it uses magnetism to generate the images. MRI compliant means that it will not be impacted by the high magnetic field generated by the MRI machine and therefore allow the images for patients with such a pacemaker.

<Trenton Gin, San Marino HS, 10th Grade>