I realize a large number of you have pace makers, and may not be well versed in defibrillators, but perhaps somebody knows the answer to this...

A pace maker sends minor electrical signals to the heart muscle causing it to beat at a set rate when it detects that the natural function is not working properly, keeping the set speed necessary to sustain our lives.

A Defibrillator sends a shock to the heart when the beats either exceed a maximum rate or stops, hopefully returning the heart back to a normal rhythm.

So for those of us who use both the pace maker and defibrillator functions, if the pace maker function of our device fails, will the defibrillator shock it back to life?

 

 

My pm/defib or bi-vent is one device with 3 leads. If one of the leads to the pacemaker is damaged, the defib lead is intact and will continue to function. The device is much more simple technologically than you give it credit for..They operate separately and the defib won't shock the pacemaker back to life. Defib would only shock ME back to life. We go in for interrogations that can tell if all the functions are working.

 

Patch,

One thing you should note. Fibrillation is actually not the lack of a heartbeat, but rather a rapid and irregular contraction of the muscle fibers of the heart. The idea behind defibrillation is that the 'shock' is supposed to depolarize the heart and allow a regular rhythm, if the sinus node is still providing one, to take back over with a normal heart beat. Since the pacemaker for those who are pacer dependent steps in for the sinus node the shocked and stilled heart should be able to pick up and beat.

The one thing a defib will not do is start a heart that has stopped if there is nothing coming from the sinus node. That is one of the big things my docs were concerned about with me. Since my problem was I was bradying down to zero if my sinus node decided to shut off my heart apparently was not going into its backup mode where it would continue to beat, even slowly. They were concerned that on one of these shut offs it would just stop, and that would be that.

Now I was told that for most people who have heart block issues if their pacer shuts down there are things in your heart that will take you to a slow but still life sustaining beat until you can get help. Shocking your heart at that point won't help if there isn't a signal coming from the sinus node (unless for some reason it woke the sinus node up).

Anyway, that is the way I understand it based upon what I was told. If anyone else has better info please post it. After all, I did just land on my head after getting hit by an SUV 8 weeks ago so things might still be a bit scrambled.

 

Hey Patch,

To come up with this question, I see you are bored s---less again.

But to answer your question - so far as I know- if the pacemaker portion of an ICD quit the heart would continue to work as it did before they got the pacemaker. Those that are 100% PM dependant could be in a world of hurt. However, that is not to say they are automatically as good as dead because the heart has an internal backup pacemaker that is located in the region of the left ventricle. Unless this has been rendered inoperable by nature or man, the heart will continue to beat at a very slow rate for a short period of time. In other words the heart will not give up without a fight.

As for the defibrillator it doesn't look for a heart beat, it looks for an abnormal heart rate. So it will not work if a person is in flat line and by I mean the person’s heart has stopped altogether. Since a defibrillator stops the heart momentarily to let it come back to life beating normally. It wouldn't make sense to stop a heart that is already stopped.

Most EMTs say that a flat line can be a very weak heart beat or fibrillation so they like to try the defibrillators as they feel it a "nothing to lose situation." Some doctors believe that CPR is just as important when a person has flat lined. CPR is known to improve the oxygenation of the heart, which it needs to begin beating again.

Now any of you that think I don't know what I'm talking about, you don't have to tell me because I probably don't. However, this is one of those subject I have read something on somewhere in all the stuff I have read about pacemakers/defibrillators over the years.

Smitty

 

So far, that's one (1) No; One (1) I don't know, and one (1) lecture

 

But it was good two see both had basically the same thing on how the heart's sinus pacemaker and internal pacemaker works... I was just lucky enough to have problems with both at the same time... Made for an interesting hospital stay and a lot of visitors very quickly when both shut down at the same time.

 

As you know I've got the 2wire with dual chamber pacer and defib......and in 3 years I've been paced out of dozens of abnormal rythmns. That last time, I got the double whammy, the pacemaker couldn't reset the rythmn on its own, and the defib. shocked my heart to stop the episode and then another one to restart the heart......that's the explaination the EP gave after the interrogation, so there by I would assume without the pacemaker (even though my dual pacemaker was trying to do its job , but failed in restoring a normal rythmn) and then I got the second Zap to start me up again.......that if your pacemaker fails, no problem, it will only be a problem if the defib. sences an abnormal rythmn for an extended period of time...or so I've been told......