- Acquired long QT syndrome associated w/many meds, including anti-arrhythmic agents
- Severe hypokalemia, hypomagnesemia, and hypocalcemia can all contribute
- Stimulant drugs/toxins (e.g. cocaine, meth)
- May have predisposing condition (e.g. depressed LV fxn, congenital long qt), where superimposed second process (as above) leads to VT
- Medical conditions that lead to electrolyte abnormalities (e.g. renal failure) or impaired ability to clear toxins (e.g. liver, kidney disease)
- Presyncope, syncope, sudden death