A 34-year-old female patient attends an emergency department complaining of sudden palpitations for the last 24 hours, with no other symptoms associated. She gives history of two other similar episodes which required in-hospital treatment, the last one occurred 4 months ago. Her vital signs are as follows: BP: 150/90 mmHg, PR = 140/min and RR = 25/min. She has a regular cardiac rhythm and no heart murmurs or carotid bruits are heard during physical examination. The patient has Crohn's disease, Hashimoto's thyroiditis, systemic arterial hypertension and type II diabetes and is currently taking mesalamine, prednisone, enalapril, levothyroxine, metformin and fluoxetine.