[Iatrogenic coronary stenosis after angioplasty].

Restenosis is the usual mechanism of recurrent myocardial ischaemia in the months following successful percutaneous transluminal coronary angioplasty (PTCA). Control coronary arteriography may occasionally show another cause: the constitution of a new stenosis near the dilated segment or in the left main coronary stem after angioplasty in a branch of this artery. The authors report 4 cases of patients who developed new coronary stenoses within a few weeks of PTCA, interpreted as traumatic complications of the initial procedure due to a lesion of the intima with a secondary fibrotic reaction and luminal narrowing. The guiding catheter was probably responsible for the trauma to the left main coronary stem whereas the tips of either the balloon catheter or the guide wire were thought to have been responsible for the endothelial effraction of the dilated vessels.