Medicine All of the following statements about third Hea sound (S3) are true, except – A Occurs due to filling of the ventricles during atrial systole B Seen in mitral regurgitation C Seen in Atrial Septal Defect (ASD) D Seen in Ventricular Septal Defect (VSD) 💡 Explanation All of the following statements about third Hea sound (S3) are true, except - ✓ Correct Answer: A. Occurs due to filling of the ventricles during atrial systole