Question

What happens if valves are not present in our hearts

Answer 1

If we do not have valves in our heart then our blood will flow downwards to the bidy instead of upwards to the heart. This may kill us too.

Answer 2

In most cases, there is also a hole between the left and right ventricles of the heart (ventricular septal defect). This defect will also lead to low-oxygen blood being pumped out to the body.  Other heart defects that can occur with absent pulmonary valve include: Abnormal tricuspid valve.