Re: what happened to the passengers of flight 93? Â« Reply #17 on: May 06, 2011, 05:33:51 pm Â». There are a lot of different theories on here about what happened. I must say that flight 93 might be the the part of 9/11 that I'm the most undecided on.here are a lot of different theories on here about what happened. I must say that flight 93 might be the the part of 9/11 that I'm the most undecided on.
Atrial fibrillation and atrial flutter are very fast electrical discharge patterns that make the atria contract very rapidly, with some of the electrical impulses reaching the ventricles and causing them to contract irregularly, faster, and less efficiently than normal.
The letter can be A (atrial only), V (ventricular only) or D (dual or both chambers). It is not difficult to identify what chamber is being paced when present on the ECG but, because most pacemakers pace on demand, a device may have the ability to pace a chamber and not be represented on the ECG.