Hi thanks for contacting HCM... Here cardiac cause has to be ruled out like left ventricular failure or any other cardiac problems. ...so investigate with ...... 1.Blood pressure checking 2.EKG 3.Tread mill stress test 4.Echo (if needed ) If still cause not clear than rule put pulmonary embolism by d dimer estimation.. If it is elevated than angiography needed ... If still cause not clear rule out respi cause by chest x ray and spirometry ...(less possibility ).... Also rule put anemia by HB estimation as complaining weakness .... According to cause treatment guided .. Hope your concern solved .... Take care. ...