 [ Symptoms ] how do you tell the difference between a cyst and something else  i found a nickel sized lump on my bikini line that hurts and is solid with a little give at the touch like cysts i have had before do but the skin above it is redish and looks bruised is it possible it is something more like a tumor or just a cyst that caused a bruise when forming [ Disease ] arrhythmias may be caused by many different factors including coronary artery disease electrolyte imbalances in your blood such as sodium or potassium changes in your heart muscle injury from a heart attack healing process after heart surgery irregular heart rhythms can also occur in otherwise normal healthy hearts what is the difference between atrial tachycardia and svt