The aim of this study is to describe thoracic radiodermatitis, a rare but not to be forgotten complication of interventional cardiology. The appearances are variable, from often oval-shaped erythema to cutaneous necrosis, with risk of chronic ulceration and malignant degeneration. The authors report 6 cases observed in 1997 after coronary angioplasty. Complex and long procedures are the main causes of this complication. Prevention requires a contribution from all the medical cardiological team, for the diagnosis, determining the indication of the type of revascularisation and for limiting the dose of X-radiation administered.