[Risk of side branch occlusion after coronary Palmaz-Schatz stenting]

The immediate and long-term patency of lesion-associated side branches after Palmaz-Schatz stent implantation was assessed by coronary angiography in 78 patients (83 lesions) at baseline, before and immediately after Palmaz-Schatz stent placement, and at 6 months. The patency of side branches was then analyzed. Of 83 lesions stented, 48 stent placements spanned 53 side branches with a diameter > or = 0.5 mm. Ten (19%) side branches were occluded before and 14 (26%) after stenting, and 4 (8%) at 6 months. Side branch ostial stenosis (> or = 50%) was present in 17 side branches; 5 (29%) with ostial stenosis became occluded before and 12 (71%) after stenting. Four of nine (44%) side branches arising from stenosis became occluded after predilatation and five (56%) after stenting. These findings demonstrate that both ostial stenosis and the location of side branches are associated with side branch occlusion.