I Am Scheduled To Have Catherization. My MD Says I

I am scheduled to have catherization. My MD says I may need stent. Forty years ago I had Stage 2 Hodgkin's Disease and have been told for decades that the sac around my heart is atrophied, the lungs are scarred thus explaining my increasing shortness of breath and fatigue. If this decades old info is accurate why a stent? And why a stent anyway since I am told that at cause more problems than solutions.