Hello nanarj. Fatigue can have a lot of causes including heart issues. I am glad that you went to your heart doctor and that you were checked out. I am assuming the your regular doctor checked a CBC to check for anemia
and hopefully a thyroid panel to check for hypothyroidism
. Both of these can cause severe fatigue
. I need to ask another question of you, have you seen any recent changes in weight?
How long have you been on the lexapro? It takes lexapro about four to six weeks to see effects. Lexapro has several doses and if you have been on it at least six weeks, talk to your regular doctor about increasing the dose if you have not seen any results.
Be well, Dr. Kimberly