Pacemaker vs ICD

Hello, I was just wondering if someome could 'dumb down' the difference between a pacemaker and an ICD. Who would need an ICD? 


Pacemaker vs ICD

by Gotrhythm - 2019-05-07 21:05:27

No matter how many bells and whistles it has, a pacemaker basically does one thing. When the heart is beating too slowly, it adds beats. A pacemaker increases your heartrate.

An ICD is an Implantable Cadiac Defibrillator. It's doing the same thing as the paddles on the chest in the ER when the doctor yells "Clear!" But it's tiny, automatic, and the charge goes directly into the heart so it takes a lot less power than the ER machine. It stops the heart temporarily to allow it to return to a normal rhythm.

Frequently an ICD is combined with a pacemaker, so that one device can both increase heart rate and deliver a shock if the heart goes into a-fib.

Does this help?


by RedRocksGirl - 2019-05-08 00:17:38

I was diagnosed with heart failure a couple years ago, when my ejection fraction kept getting lower and my heart contractions were so labored and all out of sync, my cardiologist said I should get a pacemaker to help improve the ejection fraction and make my heart chambers beat back in synch. BUT, because the hearbeat was so irregular, she said that I was at risk for sudden death and so having an ICD would be recommended. Her reasoning was if my heart stopped, the ICD would shock it, hopefully back to a regular rhythm, which could buy me time for an ambulance to get to me if needed. She described it as more of an "insurance policy", that I may never have to have it shocked but she must have felt strong enough that it was a possibility of happening to me that she strongly encouraged it. When I went to see the EP who was to do the procedure he didn't even give me an option, said that I needed an ICD instead of just a pacemaker.

I"m new to all of this as of January, but my understanding is that an ICD IS a pacemaker that has a difibrullator as part of it as well. The ICD is a little larger than a pacemaker since it houses the difibrillator parts as well as the pacemaker parts.

Thank you

by karbear6556 - 2019-05-08 11:17:49

Thank you for your replies! I’m just trying to find which is right for me. It looks like I’m going to be getting a pacemaker for sure, but I’m trying to see if I need the ICD as well. I go Brady a lot. My heart also stops sometimes so I don’t know if ICD is right for me. 


by AgentX86 - 2019-05-08 11:50:18

Note that current ICDs are also pacemakers (but not all pacemakers are ICDs). From your description,  it doesn't seem that an ICD is necessary, or desirable, but that's a decision for your EP. You may have other issues.

An ICD is useful to stop the heart in case of a dangerous runaway arrhythmia, allowing the heart to restart itself in a normal rhythm. If you don't have a high risk of these arrhythmias (primarily V-Tach or V-Fib) you don't need an ICD.



by ROBO Pop - 2019-05-08 23:14:02

Ok, so a normal resting heart rate is between 60 and 100 beats per minute, so if your heart drops below 60 then you have Bradycardia (slow heart rate). When your heart is below normal it doesn't pump enough oxygen and nutrient enriched blood tovyour organs and they slowly beging dying. A pacemaker monitors yoyr resting heart rate and when it drops below the setpoint the pacer kicks in and stimulates the heart to beat faster.

A defibrillator is designed to handle "tachycardia" or fast heart rates. It can be programmed to intervene when your heart rate is too fast and provide ATP therspy. ATP is antit- achycardia pacing which basically you can yhink of as turbo mode or overdrive. It paces your heart faster than the rste it's beating then stops and in theory your heart goes back to a normal rate. Many/most often the patient is unaware of ATP pacing. The reason they treat tachycardia is that it can lead to a deadly condition known as either fibrilaation or sudden cardiac arrest.

Then there's the big one. I call it a Jesus Jolt. When the heart goes into a rhythm so fast it no longèr beats but just quivers known as fibrillation, your device provides an instantaneous shock that stuns the heart then it starts beating normally again on it's own called sinus rhythm.

Most not all defibrillagors contain a fully functional pacemaker as well. They do not install a defibrillator unless you meet certain criteria such as a low ejection fraction(EF) of less than 30%

So do you need a defibrillator. From your description you sound like you have heart failure (AKA congestive heart failure (CHF)) WHICH MAY WELL REQUIRE A DEFIBRILLATOR BUT YOUR Cardiologist or Electrophysiologist can best answer that question as you really didn't provide the specifics necessary to determine that answer.

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