What Causes Throbbing On The Side Of Neck While Having Stent?

On my right side of my neck I'm experiencing a throbbing. It is visible and happens quite often. Is there a need for concern? I've recently have had a stent put in my left subclavian artery and a heart cath shows I have 40% blockage in my right coronary artery. I take 75 mg plavix and low dose aspirin a day