<s>[INST] I have pain across my left shoulder blade radiating though into the middle of my chest. The pain started about 3  weeks ago and is less painful at times and extremely painful at others but has never left completely. Is it something I should be concerned about? [/INST] Thanks for your question on Chat Doctor. In my opinion you should definitely consult doctor and get done1. ECG2. Stress test3. 2d echo To rule out cardiac cause. Because left sided shoulder pain with chest pain is seen commonly in cardiac cause like coronary artery disease. So get done above investigations to rule out cardiac cause. If all are normal then no need to worry much for cardiac cause. It is mostly due to muscular cause. So take painkiller and muscle relaxant. </s>