Brief Answer: take inhaled bronchodilators Detailed Answer: Hi, Thanks for your query, With such a long cardiac history it seems that your present complaint is attributable to heart disease. But if doctor is saying heart is OK, let's search for other possibilities. Shortness of breath to this extreme level can be due to various diseases like pulmonary hypertension, COPD, longstanding asthma, ILD etc. At this time get a chest x-ray done and if required get a chest CT scan done and XXXXXXX a chest specialist. In this acute phase you may try inhaled bronchodilators like combination of salbutamol ipratropium and budesonide 6 hrly. You may take a short case of steroid like prednisolone 40 mg per day under supervision of your physician for 7-10 days, This will rapidly reverse your breathlessness. Once acute phase is over, you may go for a simple breath test called spirometry to diagnose and baseline assessment of your disease. If you are a current smoker please quit it. If you are bringing out yellow phlegm, then possibly super-added infection is there and a course of antibiotic will be needed..... Best wishes

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