Hello. welcome to HCM.
heaviness under left side of ribcage could mean stomach or bowel related problems. It can even be minor or moderate splenic enlargement. Best approach will be to go in for USG scan and further investigations if needed, which will reveal the cause. In case spleen
enlargement, you need to visit hematologist
, who will search for cause. In case of bowel problems, you ned to visit gastroenterologist