Hello Sir, Thank you for posting on HCM. After going through your past history I understand that you were diagnosed with Coronary Artery Disease and that you were a chronic smoker(I appreciate you for quitting smoking completely,you completed the first milestone in your treatment ) but its unclear if you underwent any angioplasty or Coronary Artery Bypass Grafting.It will also be really helpful to know the medications you are presently taking. The pain you are suffering is called Intermittent Claudication and it is due to Peripherel Artery Disease in your lower limb.It means you you have cholesterol deposits in your lower limb arteries(Atherosclerosis,similar to your coronary arteries) and narrowing of arteries(due to your history of chronic smoking).The shortness of breath is due to the coronary artery disease.The first step is to quit smoking which you had already done.There is a drug called cilostazol for the claudication but it is usually not prescribed to patients with chronic heart disease.Other drugs like statins for increased blood cholesterol can be prescribed. My advise to you is to consult a cardiologist asap, for further evaluation and management. I hope i have helped you. Thank you.