A novel method to measure mitral valve area in patients with rheumatic mitral stenosis using three-dimensional transesophageal echocardiography: Feasibility and validation. - Mahmoud Elsayed HM; Hassan M; Nagy M; Amin A; Elguindy A; Wagdy K; Yacoub M (Echocardiography (Mount Kisco, N.Y.), 2018)