Hello! Thank you for asking on HCM! I understand your concern and would like to explain that his symptoms seem to be related to anxiety, probably related to smoke withdrawal syndrome. But based on his concerning family history for cardio-vascular events, combined with heavy smoking (as an independent risk factor for cardio-vascular disease), I would recommend consulting with the GP for a physical examination and some tests like : a resting ECG, chest x ray, thyroid hormone levels, routine blood test, kidney and liver function tests, blood electrolytes. A tread meal test may be necessary if suspicions are raised after the above tests. If all the above test result normal, I recommend consulting with a psychiatrist for anxiety. Psychotherapy may be needed. Hope to have been of help! Best regards, Dr. Iliri