What Causes Right-sided Chest Pain Post Quadruple Bypass Heart Surgery?

My husband had a quadruple bypass on 4 February but has ongoing pain on the right side of his chest spiking to feel like a knife in his right breast (the right artery to the heart was totally blocked and his heart attack was in the right shoulder spreading across the back and front) So this present pain is actually getting worse and the hospital physio on Monday said it was a mystery. He is being xrayed tomorrow. For the pain: he vomited his heart out with codeine a week or so ago and we found some tramadol prescribed I think for tooth abcess in 2013 (!!) .Anyway he s just been vomiting again from it we think. [I reckon they left a pair of scissors in his chest??] Thanks