I am gasping for breath with any exertion: showering, walking, especially up stairs, and sometimes I get out of breath just from talking for more than a couple minutes. I am 49 and have been gradually getting worse for last 3 years. My throat sometimes feels constricted and gets sore when I talk at length. Never smoked. Haven't been out of the country. I've had numerous tests, all normal: heart cath, lung scans, allergy tests, neurological, MRI, thyroid, endoscopy, chest x-rays, diaphragm radiology, and countless blood tests. I've had 2nd and 3rd opinions on many of these. Still no answers. I can't work full-time, and some days not at all.