The radial artery approach has been accepted as an alternative to the traditional femoral approach in both diagnostic and interventional procedures, including treatment of complex coronary lesions such as chronic total occlusions. Catheterization of the left internal mammary artery (LIMA) graft is frequently performed through this route in order to limit catheter manipulation and avoid dissection of the subclavian and mammary artery, a dramatic event rarely reported in the literature. Nonetheless, indication for this approach should be carefully evaluated, especially if an unfavorable angle of origin of the mammary artery is present. We report the case of a patient who, following iatrogenic dissection of the LIMA during catheterization through the left radial artery, was electively treated with percutaneous coronary angioplasty on a complex anatomy, rather than with high-risk redo coronary artery bypass surgery. Using a combined radial and femoral approach, retrograde disobstruction of the left anterior descending artery, followed by plaque debulking with rotational atherectomy through the struts of a previously implanted stent in the left main-left circumflex artery, was performed. Although the radial approach might be considered even for the treatment of complex coronary anatomy subsets, appropriate use in diagnostic and interventional settings should always be carefully evaluated.