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What's an AICD, and how could it save your life?


Modern AICD Technology: Shocking, Isn't It?
The main components of an automatic implantable cardioverter defibrillator
The main components of an automatic implantable cardioverter defibrillator
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Now that we know how heart disease can disrupt the rhythm of life, we'll take a closer look at the AICD technology that can restore that rhythm.

Your doctor may decide that an automatic implantable cardioverter defibrillator is right for you if your heart has been damaged by heart attacks or coronary artery disease, or if you have ventricular tachycardia or ventricular fibrillation. Although they can be implanted into almost anyone, people receiving an AICD average in their 60s [source: Mount Sinai]. The device can cost between $20,000 and $35,000, and Medicare may cover up to $30,000 of the cost [source: Pear].

An AICD has two main parts: the generator and the leads. The generator is a small, flat box that stores data and provides battery power. It's about the size of two saltine crackers stacked together. The leads are thin wires that connect the generator to the heart, monitor how the heart is functioning and, of course, deliver shocks to the heart when needed.

Hav­ing an AICD implanted isn't­ like ­having open-heart surgery. You may not even need general anesthesia, only numbing for the location of the incision. The generator sits beneath the skin between your pectoral tissue and your collarbone.

The two leads are directed through veins into the heart. Once in place, these two small wires actually grow into the heart tissue, and when the sealed battery dies in about seven years, those wires will be left in place, and doctors will simply replace the generator and then reattach the wires. Crazy, huh?

Before you go home after the operation (the next day, likely), your new device will be tested. Doctors will cause your heart to lose control to see if the device can restore order. They'll also hand you a long list of magnetic and electrical devices that can mess up your AICD, such as power plants and even cell phones. Regular appointments allow your doctors to check the battery's strength and download data stored in the generator. That is, the saltine-sized computer underneath your collarbone.

If your heart starts acting up, the AICD will, in a split second, review the data for a period of time preceding the onset of the problem. It then decides if it needs to speed you up, slow you down, or reset your heart. It does everything but broadcast the ballgame for you.

Now, if your heart goes into fibrillation -- remember that crazy boat going nowhere? -- the AICD sees what's happening and transmits a perfectly timed big jolt that stops your heart for about half a second, allowing the SA node to restore order and reestablish the dominance of its electrical pulse.

You might be passed out when you receive this shock. Otherwise, it's going to feel like you've been kicked in the chest. If you weren't already on the ground, you very well may be after your heart has been stopped with a blast of electricity. But it beats flopping around and dying in a state of fibrillation.

After the AICD is implanted, you'll need to tone it down for a while. If you follow your doctor's instructions, you should able to return to your pre-implant activities within a few months. Some people find they have even more energy than before. But even if you don't decide to join a competitive rowing team after your AICD is implanted, take heart: You'll still be doing much better than 100 percent of dead people.

See the next page for lots more information that could keep your heart happy and healthy.


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