I suffered them for about 4 years. They had me on meds, it did not help, just seemed to make it worse. After numerous tests, they found that I had hypoglycemia, was into menopause, and also tested positive for an auto immune disease. I did not give up, I knew I was not depressed, I knew it had a physical cause, which was confirmed by my doctors, and my counselor. You have to listen to your heart, and what it is telling you, not what the experts say. They don't walk in your shoes, you do. The possible physical causes are hypoglycemia, hormones, carbon monoxide, thyroid disorder, among many others, as well as skipping meals, asthma, asthma medications, a heart condition(murmur), many medications, magnesium deficiency, trytophan deficiency, and food allergies. A physical may be in order, to rule out a physical cause. A heart murmur is hard to detect, and is most prevalent when you are sick say with bronchitis, because of a lack of oxygen. Until the underlying cause was found, they did not subside. Read my article on meno, for supplements, and advice. I hope this helps.