I ve noticed that my lower left hand rib cage/upper abdomen is protruding greatly over the past few weeks. It stays swollen. It feels very uncomfortable, more noticeable after eating, as if there is something pressing against it -it s worse when I m sitting than standing. I have no idea if that is related to something else that has also been happening off and on over the past few weeks. I have sudden intense heart beats that go away after a minute, or a few. It seems to primarily happen when I m wearing a bra, I feel almost immediate relief if I lift the bra away from my left rib/center. Also, the rib is uncomfortable when wearing a bra. Not sure if they re related, or if it s just odd timing. I m curious what this might be.