Reply #34: I'm glad the docs are looking...

[hue]

electrolyte imbalances can cause arrhythmias as electrical conduction of the heart needs potassium & other electrolytes to be in proper balance. They always render a person more prone to arrhythmias. They may, in the end, upgrade His pacer to one that has a defibrillator built in. (Those ICDs (implantable cardiac defibrillator) always attempt to pace the Patient out of the arrhythmia before shocking so they are safer than they sound.
That fact that He has a pacer already & "passed out" makes it almost certain an arrhythmia overrode or overpowered the pacemaker. If He has a bladder infection or any infection they will not do a cardiac catheterization until the infection is cleared up. He may be in a tad of acute kidney failure at this time also.