S4 is not seen in-
A fouh hea sound is commonlyheard due to decreased ventricular compliance. It can sometimes heard immideatly before the first sound when atrial pressure is high or the ventricle is stiff in conditions like ventricular hyperophy. Ref Harrison 20th edition pg 1557
Ventricular aneurysm
Mitral regurgitation
Hyperophic cardiomyopathy
Hypeension
C.V.S