Please advice me what can I do. Ago?

My mother underwent surgery for an ovarian cyst and hysterectomy 9 days ago. Since the surgery, she has developed severe chest pain, mainly on the left side of the chest, along with pain extending toward the back. We consulted a doctor, who told us that the symptoms are suggestive of a heart attack. However, the doctor also said that because she recently underwent surgery, he cannot perform angiography or angioplasty at this time and advised us to  take her home, give her rest, and continue Ecosprin 20/75. She has been taking the prescribed Ecosprin 20/75, but it has not provided any relief from the chest pain. We are very concerned because the chest pain is severe and persistent, and we want to know what should be done next. Is there any safe and appropriate treatment or investigation that can be performed at this stage, considering that she had major surgery only 9 days ago?