Both diastolic heart failure and systolic heart failure are classified as left-sided heart failure. The left ventricle supplies most of the heart's pumping power, so it's larger than the other chambers and essential for normal function. Drug treatments are different for the two types.
Diastolic heart failure is heart failure with preserved ejection fraction (or diastolic dysfunction): In this case, the left ventricle loses its ability to relax normally (because the muscle has become stiff). The heart can't properly fill with blood during the resting period between each beat.
Systolic heart failure is heart failure with reduced ejection fraction. In this case, the left ventricle loses its ability to contract normally so that the heart can't pump with enough force to push enough blood into circulation.
Despite the differences on treatments, there are some tips for both cases:
Medications recommended by the doctor
Devices and surgical procedures
Changes in lifestyle and diet