Normally, splitting of heart sound (S2) occurs upon inspiration when aortic valve closes earlier than pulmonary valve. It is normal. Wide splitting is an abnormal occurrence which occurs in conditions associated with delay in the emptying of right ventricle. It is the auscultation of splitting of S2 during expiration. Wide splitting of S2 occurs in - Atrial Septal Defect (ASD) - Pulmonary stenosis - Complete Right Bundle Branch Block (RBBB) - Pulmonary Arterial Hypertension -