Hello. Thank you for your question and welcome to HCM. I carefully read your query. Some times, there is a good possibility that coronary artery disease can be presented in an atypical pattern - meaning, without chest pain - with shortness of breath, palpitations, epigastric pain, malaise etc. Since he also is a stent patient, I would recommend him to do a cardiac stress test, to see if there is any evidence or coronary artery disease or problem with the implanted stent. I assume that the curing doctor explained to him that there is a probability of within stent narrowing, after successful implantation. In case of bare metal stents, this probability is 16-25%, and in case of drug-eluting stents, this probability is 4-8%, depending on the stent coating. Hence, my recommendation for a control, so, even if this is nothing to worry about and the stent is fine, at least we can exclude the cardiac and coronary origin with higher probability. If the cardiac stress test results come back positive, then another coronary angiography to check the native arteries and the stent, would be appropriate. Also, if this stent was implanted in a scenario of acute myocardial infarction, the infarcted muscle itself can damage one wall of the heart and, therefore, drop the function of the heart. If this is the case, then the shortness of breath may come from the raised pressures in an insufficient heart, which causes high pressures in upper floors - the lungs, hence the shortness of breath. If this is the case, I recommend him to discuss with his doctor about the possibility of adding furosemide and spironolactone (depending on the heart function) on the therapy. The shortness of breath can primarily come also from the lungs or any change in the airways. I would also recommend a plain postero-anterior and lateral chest X-ray. I hope I was helpful with my answer. Wish you a good health. Best regards, Dr. Meriton