Septal bounce

Paradoxical septal motion (or septal bounce) is frequently seen in the period immediately following cardiopulmonary bypass if ventricular epicardial pacing is employed. This can be distinguished from septal dyskinesis by (1) thickening of the myocardium despite the motion of the endocardium and (2) normal septal movement if ventricular pacing is paused. This assumes an underlying rhythm with AV conduction.