Coronary angiography (CAG) was performed on a 78-year-old female patient due to class III angina. A calcified critical obstruction was demonstrated in the right coronary artery (RCA). An attempt at percutaneous transluminal coronary angioplasty (PTCA) failed to dilatate the lesion despite high balloon pressure. In a second attempt the lesion was dilatated with the balloon after implementing a tornus penetration device, and then a stent was implanted. A dissection occurred after the stent implantation and it was treated with another stent. The treatment of lesions that cannot be dilatated using conventional PTCA techniques and the role of the tornus penetration device in such cases are discussed.