The present invention provides compositions and methods of inhibiting tyrosine phosphorylation. In one aspect, a composition comprising a low-dosage tyrosine kinase inhibitor, where the low-dosage tyrosine kinase inhibitor decreases tyrosine phosphorylation, is provided. In another aspect, a method for treating cardiovascular disease or condition associated with a RASopathy having aberrant protein tyrosine phosphorylation is described. Methods for treating congenital heart disease associated with Noonan or Noonan syndrome with multiple lentigines and decreasing aberrant levels of Protein Zero-Related (PZR) tyrosyl phosphorylation are also described.
