The Barlow's syndrome is a disease characterized by the presence of mitral valve prolapse and a wide range of signs and symptoms. We know that its manifestations has a great variety existing cases with little clinical expression as those seen frequently in daily practice or the other side opposite completely in which, the syndrome is so complex getting to the patient to present many symptoms secondary to hemodynamics alterations that reduce by much its quality of life and even modify its prognosis.The case that we present is a female patient of 25 years old with Barlow's syndrome and functional class II-III of NewYork Heart Association as a result of the alterations in the contractility function of the heart that finally caused her death.