ABSTRACTMitral valve prolapse syndrome is the most common cardiac disorder today. However, it is relatively new in the medical literature and not well understood by most health care professionals. This article discusses the history, pathophysiology and etiology of the syndrome. An in-depth study of the psychological aspects of the disease is also presented. The syndrome is considered by some authors to be the same as soldier's heart and neurocirculatory asthenia. Mitral valve prolapse syndrome can produce disabling symptoms such as chest pain, chronic anxiety, syncope and many others. The cause of these symptoms is not well understood. Autonomic dysfunction and a congenital brain malfunction are proposed explanations for the symptoms. Nurse practitioners who are aware of and knowledgeable about this disease can provide an invaluable service to those afflicted with it.