Does an infant with borderline left ventricle and aortic stenosis and other associated problems can live a normal healthy life or will compromise ?

Depends on severity: Any baby with a congenital heart defect is worrisome. Depending on the type of defect (can be very minor to sometimes fatal), each baby will have a different outcome. The pediatric cardiologist caring for the baby knows the most because he has many other children as patients, who have similar heart defects. He can estimate the outcome but won't be able to make exact predictions.

It also depends on: Whether the infant has an associated genetic abnormality, as ~30% of infants with chd do. Pediatric cardiologists usually refer to a geneticist, even if chromosomes on amnio were normal. It's hard not to be hypervigilant about every little thing, so ask his cardiologist & cardiovascular surgeon exactly what symptoms may spell trouble. He may qualify for early intervention to help development.

Likely Compromise: Unfortunately, a "borderline" left ventricle and as will likely have some long term effect. That does not mean your child cannot live a meaningful and happy life. As a cardiologist, i can tell you that there are too many unknowns to begin to speculate. But if things go well (i.e. Surgery/cath) your child can do well and be happy.