Which heart valve works harder, the bicuspid or tricuspid?

Both.: I suspect most would say the bicuspid as the pressures are greater, but i kind of like them both. The tricuspid has one more leaf doesn't that count for something?

Do you care?: Who cares? All valves have to work or you're dead.

Four heart valves: All 4 of your heart valves have three cusps. If you have a heart valve with 2 cusps that is a common congenital anomaly. A bicusp heart valve does not perform as well as a regular three cusp valve over a lifetime. Occasionally the bicusp valve will need repair or replace. The four valves are named; pulmonary, aortic, tricuspid and mitral. Be well.