Inclusion criteria:  Patients with symptomatic paroxysmal or persistent Atrial Fibrillation on the waiting list for AF ablation at Queen Elizabeth Hospital Birmingham who  are more than 18 and less than 80 of age, have paroxysmal or persistent AF, symptomatic: palpitations, shortness of breath, feeling of an irregular pulse or pause in heart activity, light-headedness, or dizziness) despite pharmacological anti-arrhythmic agents (or inability to take medications) therefore making them eligible for ablation therapy, are above BMI- 30 kg/m2  Exclusion criteria:  Any one of the followings;  unable to undergo CMR, Patients who are currently treated with a weight losing drug - including Orlistat, GLP-1 analogues or have had/or awaiting bariatric surgery, Type 1 diabetes, Type 2 diabetes on DPP-IV inhibitor or insulin: as blood sugar will need close monitoring on GLP-1 and insulin, Patients with decompensated liver disease, end-stage renal disease or eGFR <30, NYHA class III/IV heart failure or active malignancy, Any malignancy within the last 2 years except skin malignancies, Pregnancy, Patients with a history of thyroid cancer or pancreatitis, Patients with a needle phobia.