Case #3 Answers
Her condition worsened by the change from Metoprolol to Amlodipine due to loss of inadequate rate control.
It would be very unlikely to be successful at cardioversion and then maintenance of the long standing duration of atrial fibrillation.
CHA2DS2-VaSc= 9. Chronic anticoagulation should be recommended.
This patient should be treated with a rate control strategy, pharmacologically at first. If this fails, would recommend AV node ablation and insertion of single chamber vs BiV pacer (or ICD depending on LVEF and clinical status).