The purpose of this study is to determine if women with chest pain and "clean" heart blood vessels have impaired blood flow to the heart due to problems with the small blood vessels that provide blood and oxygen to the heart. Impairment in the small blood vessels will be tested using ultrasound pictures of the heart, called myocardial contrast echocardiography. Since these small blood vessels are not seen in a coronary angiogram, which is an x-ray of the heart vessels using a dye containing iodine injected in the heart vessels, the problem may remain undiagnosed in women until the heart muscle becomes severely damaged.
A second purpose is to identify if there is a common trait in the population of women with this tiny blood vessel dysfunction, which will be investigated by checking blood levels of certain chemical and hormones related to heart disease. Finally, we would like to investigate the relationship between depression and stress, and heart disease. We will do this by measuring cortisol (a hormone that serves as a measure of stress) and administering questionnaires that help to identify depression and stress.