If a patient talks about what it feels like to be defibrillated, how do they describe it?

Well, very often when you have fibrillation, you pass out. So you will not feel it very often. But in the case of atrial fibrillation, sometimes you have AF atrial fibrillation, you have to go to the doctors and then they're going to do a defibrillation. They have to do a shock. In the case of a student of mine, he tells me that he got AF and then he went to the hospital and they were in order to carry him, they gave him some sedative. So he was sedated. And then he says he remembers hearing someone screaming. And then later on, they told him, no, it was him screaming from the shock, but he did remember it was him. So the shock is big enough that is painful. That's why they sedate you. And that's why actually it's very important when they do a defibrillation, they have to hook it up to the ECG. Because as I mentioned, when they go into defibrillating the AF, you hook up to the ECG so you know when you do the shock, you don't do it during the T-wave, at the end of the T-wave, because then you can initiate fibrillation in the ventricles. They always, every time they defibrillate you, they hook it to the ECG and then they do the shock

at the safe time. So you've mentioned now, and I don't think we've emphasized this distinction so far, so we should probably should. Atrial versus ventricular fibrillation. I remember some years ago we had a president, I think it was President George Bush, the elder, the father of George W. Bush, who if I remember had atrial fibrillation as a kind of chronic, like he lived with it, if I'm remembering right. Yeah, I think so. Ventricular fibrillation, if untreated, will be deadly because you're not pumping any blood. But atrial fibrillation is something you can live with?

Yes, so this is the separation, as you were saying, between if a relation happens in the ventricles, you have to defibrillate within seconds, minutes, right? The longer you take to defibrillate, the harder it is to defibrillate because it should become less excitable, because there's less oxygen, and then you have less oxygen to the brain, and the chances to recover are very low. So you have to really defibrillate very quickly in the ventricles. In the atria, the atria and the ventricle are physically connected, but electrical is connected. You have fibrillation in the atria. Still the ventricles can contract, not completely regularly, but can contract and send blood to the body. So atrial fibrillation, you can leave, but you always have, you feel tired, you cannot really move because the ventricles are not contracting as good as they could. And there's also, because the atria is not pumping blood continuously, some of the blood can remain there, and it's easier to produce clots of blood, the clots can go into the body, and then it can give you a stroke. So when you have af, it increases your chances to have a stroke. And af, it happens to most people when you get older, well, not most people, but as you get older, there's more higher chances to have af. About 2.2 million people in the US have af, like 70% of people with af are between 65 and 85 years old. And one of the interesting things about af is that it starts slowly, so then it just, the waves start breaking and producing spiral waves, but then they disappear, they go away. So self-terminates. But as they keep appearing every now and more, the longer it appears, the longer they remain. So the more often you get af, the longer the episodes, and the harder it is to terminate. So if you start developing af, you want to try to go to the doctors and get either medications or other methods that are called like ablation, they can go inside it with a catheter and then burn sections of the atria. So then these waves don't have space enough to rotate, and then they self-terminate. So they're methods to try to terminate their readmeas, and they work better the sooner you find out you have af, because as longer is very interesting as it happens, it also remoders the tissue. So the tissue becomes a little bit larger and also the electrophysiologists' remodals as well. So every time that you have more free relation, it's easier to continue the free relation for longer until it becomes sustained. And once you sustain, the only way to do it is basically these kinds of ablations that they have to go there.