If the valves of the heart do not close, the blood will flow backwards. Blood will escape back into the chambers rather than flowing forward through the heart or into an artery.
You may suffer from Rhd, Or worst have a heart attack.
Rhd is a rare disease that means the valves isn't working properly, it either your family history or a disease you just discover yourself. The hearth pumps blood but if the valve don't work you may have blood clothing,the blood will thickens and will not flow that leads to heart attack.
The backflow of blood may not be prevented which could lead to death.
The blood will mix. And the wouldn't function well.