Is it the stiffness in heart muscles which can cause diastolic dysfunction?

Dear Student, 

In diastolic dysfunction the diastolic action tends to be abnormal. The ventricles do not properly relax and becomes stiff due to which blood does not fills up properly in ventricles leading to block passage to other organs. So in diastolic dysfunction we look for stiffness of ventricles particularly not whole heart and thickness of ventricles.

Regards