Well I guess you could have several problems depending on if the valve either stays closed or open or just leaks.just like if you tied off a hose or opened it wide open. Either not enough blood flowing or no back pressure for pumping the blood. Or loss of control of how the blood flows.in other words your circulation could become poor causing other problems.since I am not a heart specialist I would talk to a heart(cardiac) doctor about the possible problems that could be caused by a faulty valve.they have came a long way since one of my relatives went in for theirs.