Hi and thank you for your question. Your father s cough is considered a chronic cough since it lasted for more than 8 weeks. The causes of chronic cough are many and to judge better about its cause it would help me to know a bit more of his cough carachteristics and his medication history .In the setting of heart disease my first concern is that the highest propability of its cause is related with heart insuficiency especially if the cough is nocturnal and the cough has pink frothy secretions.In this situation the treatmentis that for heart insuficiency and pulmonary edema.If your father is taking an antihypertensive medication that is part of a group called A C E inhibitor like enalapril,ramipril this also is a cause of chronic cough in a group of patients and it may begin anytime between hours to months after the first dose.The solution is to stop this medicament.Does your father smoke or has smoked in the past ?He is taking an inhaler for his breathing problems so i can not exclude a chronic bronchitis and in this case if i was his treating doctor i would order a chest xray,pulmonary function test to decide for the treatment.I hope my opinion can be a help to you. Kind regards Dr.Dushi