<s>[INST] I amgetting fluttering in the chest. It feels like my heart is actually missing beats. It happens at odd times, like when I am relaxed, or when driving. I do not feel stressed so wonder what it is. I am 50, female, a little overweight but not too much. It happens two or three times a week and I feel as if Icant breath...I can but thats what it feels like. [/INST] Hello, Most probably these ventricular ectopic. You should get one ECG done, if normal then needs holder monitoring for 24 hrs which will most probably pick the abnormalities in heart rhythm. Later, you'll also need thyroid test, if having menstrual irregularities then hormonal profile as well.  Most of the time these are benign and not worrisome. So we need to confirm the diagnosis and then go ahead accordingly. Hope this helps you and get back if you have any questions. </s>