Safety and effectiveness of stent implantation without predilation for small coronary arteries

The purpose of this study was to examine the safety and effectiveness of stenting without predilation (direct stenting) in small (< 2.5 mm) coronary arteries. Clinical and angiographic data from the multicenter randomized PREDICT trial was examined. Direct stenting was performed on 42 small and 158 large vessels. Predilation was performed prior to stenting for 37 small vessels. In the small-vessel group, mean reference vessel diameter was 2.24 +/- 0.19 mm for direct stenting vs. 2.24 +/- 0.22 mm for predilation (P = NS). Mean reference vessel diameter was 3.17 +/- 0.48 mm in the large-vessel group. Device success for direct stenting was similar for small vs. large vessels (90.5% vs. 92.4%; P = NS). At 180 days, a trend toward increased MACE between small vs. large vessels in the direct-stenting group was observed (26.8% vs.16.7%; P = NS), and significantly higher target lesion revascularizations (TLRs) in the small-vessel group (19.5% vs.7.7%; P = 0.03) were observed. In small vessels, differences in device success rate (90.5% vs. 100 %; P = NS) and lesion success rate (100% vs. 100%; P = NS) for direct stenting vs. predilation were not significant. At 180 days, no differences between direct stenting and predilation for MACE (26.8% vs. 29.7%; P = NS) or TLR (22.0% vs. 21.6%; P = NS) were seen in small vessels, although binary angiographic restenosis rate tended to be higher in direct-stenting group (38.2% vs. 18.5%; P = NS). Direct stenting of small vessels can be performed safely and successfully in selected cases. Restenosis rates may be higher for small vessel treated by direct stenting compared to predilation.