Hi Since your mother had an angioplasty done two weeks ago following a heart attack, there are chances of complications like stent thrombosis, arrhythmia leading to heart failure leading to accumulation of water in the lungs (as confirmed with chest X-ray) resulting in cough with frothy sputum. There are also chances of hospital acquired lung infections. It is important to get a look on her pre-angioplasty echocardiogram and her cardiac function. According to your description, she had cough even before the coronary stenting. I would like to know whether she had any associated symptoms or allergies. Does she wake up at night due to breathlessness? Consult the emergency or the cardiologist at the earliest to assess the cardiac function with an echocardiogram. Also, conduct a laboratory work up with renal function tests and serum electrolytes. Furthermore, consult a pulmonologist to rule out any underlying lung pathology for chronic cough. If she is diagnosed with heart failure, she would be prescribed with diuretics and water restriction to prevent accumulation of water in the lungs. I would advise to avoid strenuous activities. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Devi Venugopal Rita, Internal Medicine Specialist