A quadricuspid aortic valve (QAV) is a rare congenital heart defect characterized by the presence of four cusps, instead of the usual three found normally in the aortic valve. It is a defect that occurs during embryological development of the aortic trunk during gestation. There is an increased risk of developing post-natal aortic regurgitations and other heart-related diseases; therefore patients with the condition should be carefully monitored. Signs and symptoms
Complications
The most common complications of QAV are aortic regurgitations. This is caused by the inadequate closing of the four cusps at the end of systole. The fourth dysplastic cusp is incapable of fully closing the aortic annulus, which causes a backflow of blood through the aortic valve. Using transthoracic echocardiograms, 3-D TEE and ECG traces, it is also possible to find left ventricular hypertrophy, bundle branch blocks, and abnormal displacement of the ostium in the right coronary artery in association with QAV. Some research has shown increased incidences of atrial fibrillation to be associated but this relationship is not yet clearly established. Diagnosis
Previously, diagnosis was usually done through autopsy. Advances in imaging technologies allow for early detection and thus ample treatment and monitoring of the affected patient. A short-axis ultrasound of the aortic valve allows for the best view of the aortic valve, and gives a clear indication of the adduction pattern of the aortic valves.If an “X” shape is seen, then the patient can be diagnosed with having a quadricuspid aortic valve.
Younger patients start out having unimpaired vision, but it starts to deteriorate at a young age and does so slowly. If vision is able to improve with the use of glasses, they should be worn to help facilitate concept development. Retinal degeneration cannot be ameliorated with glasses.The type of therapy needed for each individual varies, as not every affected individual would benefit from speech, physical, and occupational therapies. The type of therapy for each person is highly individualized. Individuals who have Cohen syndrome may also benefit from psychosocial support.Many people who have Cohen syndrome also have neutropenia which is a condition in which an individual has an abnormally low number of white blood cells called neutrophils. Having this condition may make these individuals susceptible to infections. Granulocyte-colony stimulating factor (G-CSF) is one possible treatment for neutropenia.Monitoring weight gain and growth is crucial, as well as annual ophthalmologic and hematologic evaluations and checkups. While there are treatments available to people with Cohen syndrome, there are no known cures for the disease. Prevalence
Over the past several years, there have been approximately 50 new cases worldwide. There are population groups with this condition in Australia, New Zealand, the UK and the US. It still seems to go undiagnosed, leaving the number of known cases less than 500. Etymology
The syndrome is named after Michael Cohen, William Pepper and Jaroslav Cervenka, who researched the illness. References
External links

GeneReview/NIH/UW entry on Cohen syndrome