When the valves are replaced and repaired，the heart function can be improved obviously，and the symptoms of heart failure including cough, shortness of breath, can also disappear obviously.
If you still have a chronic cough after surgery, you need to first determine your heart functions.
If the echocardiography indicates that the cardiac function has declined, and there is both cough and expectoration (not dry cough), it can be treated with drugs such as diuresis and heart function protection. After improving the cardiac function, the cough should be relieved.
If the heart function is OK, you need to check whether you have taken an ACE inhibitor recently to reduce blood pressure. If so, you can ask your cardiologist to adjust your antihypertensive drugs.
Of course, coughing may also be caused by lung inflammation. You need to take a chest CT scan. If there is lung inflammation, antibiotics should be given as early as possible.