Would ans dysfunction cause sinus tachycardia or another type of arrythmia? would it cause elevated epinephrine?

Dysrhythmia: The elevated epinephrine levels from whatever, causes the arrhythmia and not vice versa as a rule. I would look for other causes like anxiety, stress, fever, anemia,caffeine,alcohol,nicotine,hyperthyroidism,etc before attributing the condition to ANS. Your cardiologist and personal physician are best qualified to evaluate the dysrhythmia and its causes however.