What does it mean when heart fluttering is stong and painful, accompanied with difficulty breathing? Every now and then I get this feeling in my chest like my heart is fluttering. It is deep and strong, it almost feels like my heart is trying to pull up and out of my mouth. It hurts and pulls my mouth open. I can t move or breathe when it happens. It lasts about three seconds or so. It really freaks me out... Also lately, a lot of different muscle groups throughout my body have been twitching: upper arm, calves, and even random small muscles in my abdomen, back, and face. I don t get the deep fluttering sensation too often, maybe about once a week, but lately I ve been getting it several times a day so it s starting to worry me. The muscle twitching and difficulty relaxing muscles once they are tensed is also getting worse. Any idea what s going on? I m starting to get concerned. Yeah... not so much a big meat, egg, or cheese eater. I don t get very much cholesterol (sp?) in my diet, or much protein either for that matter.