Are there an major complications that might come from corrected my sons vsd?

Yes. Serious complications of vsd repair are very uncommon. They include bleeding, infection, and brain injury. There is also a small risk of damage to the conduction system of the heart that would require a permanent pacemaker. The risk of dying from the procedure is exceedingly low, but not zero.
Ask Surgeon. Ask your pediatric cardiac surgeon to explain about the particular possible complications for the particular type of vsd that your son's heart has or had.