Bicuspid aortic valve (BAV) is the most common congenital heart anomaly in the general population (1-2% of all individuals). In affected people, the aortic valve (the structure ensuring one way blood flow between the heart's left pumping chamber, the left ventricle and the main body artery, the aorta) consists of 2 rather than 3 leaflets. This arrangement can cause the affected valve to have restricted opening or cause it to leak. Both situations put strain on the heart and patients with BAV across the age range may require surgery to replace the affected valve. BAV is therefore a condition associated with significant ill health and early mortality. BAV is known to cluster in families and is likely to have a genetic cause. We don't fully understand the inheritance of BAV or the specific genes involved in its development. Learning more about this is the basis of the BRAVE study. We will ask patients with BAV and their relatives (who may or may not have BAV) to take part in the study. Blood samples obtained from the participants will be used for analyses of their genetic composition. This information, linked with the clinical data concerning who does and does not have BAV, will potentially enable the identification of the gene changes responsible for the disease. This, we hope, will give us a much better understanding of the mechanisms leading to this serious and common condition.