My ultra sound for carotid artery showed, "mild noncalcified plaquenin carotid systems bilaterally" should i be worried?-(healthy 70 year old male)

No: Only when the obstruction is around 70% or higher we recommend surgery ( endarterectomy or scraping of the plaques ) but we order an mra or dsa to confirm it . In the mean time you could take 81 mg of Aspirin (if not allergic or contraindicated )and lower your cholesterol as much as you can..

Not really: Watch your risk factors- see stroke.Org. No smoking. See your doctor to see if you need to take Aspirin or a statin or blood pressure medicine.