NIH nhlbi.nih.gov nhlbi.nih.gov ventricular septal defect atrial septal defect ventricular septal defect What Are Holes in the Heart? heart defects holes in the heart ventricular septal defect ventricular septal defect holes in the heart What Are Holes in the Heart? congenital defects or "holes" in the heart "hole in the heart" defects nhlbi.nih.gov walls of the heart's chambers congenital defects or "holes" in the heart walls of the heart's chambers hole ventricular septal defect “hole in the heart” "hole in the heart" defects walls of the heart's chambers