Hello there ! The heart has four valves- two on the right and two on the left side. From your query it appears that either one or both valves on the left side of your heart are malfunctioning. To an extent the problem can be managed by medicines but only upto a point. Surgery is recommended once the medicines stop having the required effect. In your case it appears the valve on the left side are not functioning well enough for medication to work properly and therefore may need surgery to restore function. I hope this answers your query. Please let me know iif you need any clarification.. Best of luck!