The Celermajer index is a score used to evaluate the severity of Ebstein anomaly (\(EA\)). It is calculated using echocardiography.  Explanation The Celermajer index is a ratio of the area of the right atrium and atrialized right ventricle to the area of the functional right ventricle, left atrium, and left ventricle.  The Celermajer index is used to grade the severity of \(EA\).  The Celermajer index is also used to predict mortality.  Grades of the Celermajer index  Grade 1: \(Cel-ind\) < 0.5 Grade 2: \(Cel-ind\) 0.5 to 0.99 Grade 3: \(Cel-ind\) 1.0 to 1.49 Grade 4: \(Cel-ind\) > 1.5