Patients having acute cardiac failure do not show oedema, because :

D i.e. There is fall in systemic capillary hydrostatic pressureEdema normally occurs due to increased hydrostatic pressure that pushes fluid out or due to reduced oncotic pressure that fails to pull the fluid.Acute hea failure is usually predominantly systolic and sudden reduction in cardiac output often result in systemic hypotension without peripheral edema.Acute hea failure is associated with a fall in hydrostatic pressure and therefore explains lack of peripheral edema.