Red Bull and tachycardia

Has anyone ever tried to listen to themselves after drinking Red Bull, or to listen to the heart of someone who had drunk it? Years ago I had to take a long car trip at night and I drank two Red Bulls. I had tachycardia for the whole next day.

I am a caffeine afficionado, so I don't get much of a change in heart rate from it. Used to drink a lot of energy drinks (have cut back a lot and stick mostly to coffee now) and that would at times get a 5-10 beats/minute increase and my heart would feel a little "thumpier" (particularly if I drank it quickly). The bigger thing for me is caffeine is kind of an aphrodisiac for me. Not in a "I will go compulsively have sex" kind of way, but if I drink a bunch of caffeine rather quickly and don't have other things going on, I often end up getting pretty horny and masturbating.

I used to drink 4-5 large cups of coffee every morning at work, and I'd actually have frequent PVC's at times. got me to slow down on the coffee intake.