[Acceleration of the left main coronary artery stenosis following PTCA: a report of a case].

Acceleration of the left main coronary artery (LMCA) stenosis induced by guiding catheter which was used for percutaneous transluminal coronary angioplasty (PTCA) was demonstrated in a 68 years old man with post-infarction angina. He underwent PTCA to a subtotal lesion in the left anterior descending coronary artery (LAD). The LMCA with mild stenosis of 18% reduction of luminal diameter was unchanged during the course of PTCA. The guiding catheter was pushed repeatedly with considerable force for introducing balloon catheter due to the rigid lesion in LAD. Progression of the LMCA stenosis to a 64% was demonstrated at 6 months later angiographic restudy. It was considered that repetitive sliding of guiding catheter through the LMCA caused subangiographic intimal trauma and facilitate subsequent progression of stenosis. We examined the guiding catheter to the LMCA diameter ratio, the angle of the tip portion of the guiding catheter with LMCA, and severity of the target lesion in this case compared with other 27 controls in whom PTCA was performed to the lesion in left coronary artery. No difference of these 3 factors between this case and other 27 controls was obtained. Thus it might be difficult to predict progression of LMCA stenosis by these angiographic factors. Although the incidence of catheter-induced progression of LMCA stenosis was as low as 1 of 160 cases (0.6%) in our experience, it is important to attend to catheter-induced progression of LMCA stenosis and to make an early detection.