I have read that many people are experiencing the fluttering under the left breast.  It could also be described as a vibration if my cell phone was in my lewft pocket.  It is not painful, but is concerning because it happens a lot....almost continually.  I have AFib and am on xarelto and also am on diovan and metroprolol for HBP.  Could anyone comment or tell me if this could me serious.  I am about to get on a flight, and am now wondering if I should.