What noticeable signs are there of a congenital heart defect? what is the usual cause?

Blueish color murmur: Decreased oxygen saturation tends to render a purplish/blueish hue to the lips and/or digits in cases of complex congenital cardiac defects. Additionally, heart murmurs and symptoms of weakness, shortness of breath, dizziness with exercise can all be seen with such defects. Consult with a pediatric cardiologist and cardiovascular surgeon for repair/management.