Advantages of Tissue Valves 

Need for anticoagulation therapy is only for a short duration in xenograft and only there is rare need for anticoagulation therapy in autograft and allograft tissues. Thrombogenicity is low in biologic tissue valves. The cost of the valve is low.

Disadvantages

Tendency for early calcification and tissue degeneration is high and durability is limited. Biological valves may be preferred in patients who cannot take anticoagulant therapy e.g. women of child-bearing age. Age below 18 years and very old person (after 70 years).