anteroseptal wall ischemia

My mother was diagnosed with Ischemia of the anterior septal wall. Way back before she was taking Isordyl for her angina, but this past few months she always feel the heartburn or sometimes mistaken as her hyperacidity 'coz she also has one. But then she recently found out that the heartburn-like chest pain and numbness of her left arm is already the cause of this certain diagnosis. Her Doctor in the Philippines prescribed her with Trimetazidine (Vestar) and Simvastatin (vidastat), do the stress test and ask her to come back after 6 weeks. I am very worried about the condition of my mom. Does she need to undergo to a surgery?....pls help...thanks..