Ever had that patient that you just weren’t sure what pathway they fit in?

You have a 75 yo F who called 911 due to palpitations and increasing shortness of breath. She looks fairly comfortable with belies the rate of 180 seen on the monitor. She does endorse some chest discomfort. No previous drug use, no recent surgery/ Rhythm might be irregular but it’s too hard to tell at that rate. Should I cardiovert? Should I give them diltiazem? Could this tachycardia be reactive to something, and I should look for other potential issues?

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