Question category: Cardiology
A 30 year old woman presents with palpitations. She is found to have a regular tachycardia of 200 bpm. She is normally fit and healthy and has no past medical history however drinks 5 mugs of coffee per day and uses alcohol excessively. She is not compromised with a blood pressure of 130/80mmHg with no chest pain and no signs of heart failure. Her bloods are all within normal parameters however the ECG confirms a narrow complex tachycardia of 200 bpm. If after giving IV adenosine 3mg and then 6mg this fails what should be the next management step?