AIMS: Recent reports have suggested susceptibility of novel thin-strut coronary stents to incur longitudinal stent deformation during or following deployment. This analysis assesses the incidence of longitudinal stent deformation in three stent platforms. METHODS AND RESULTS: Quantitative angiographic analysis (QCA) of 2,403 stents from the PERSEUS Workhorse (WH) and PLATINUM-WH trials was performed by an independent core laboratory. The distribution of QCA measured: nominal stent length ratios was compared between platforms to evaluate longitudinal stent deformation. Stent length ratio averaged 0.95 +/- 0.07 in the TAXUS Express arm and 0.94 +/- 0.06 in the ION (TAXUS Element) arm of the PERSEUS-WH trial (p=0.16). In the PLATINUM-WH trial, the mean ratio in the PROMUS cohort was slightly smaller (0.92 +/- 0.09) than PROMUS Element (0.94 +/- 0.08; p=0.004). Manual, blinded re-examination by the core laboratory of the angiograms corresponding to the 20 lowest and highest ratios in each trial did not identify any cases of stent deformation. CONCLUSIONS: Systematic analysis by an independent angiographic core laboratory of 2,403 stents implanted in patients enrolled in two large multicentre randomised trials demonstrated no stent deformation or meaningful differences in stent length ratios between ION and TAXUS Express or between PROMUS Element and PROMUS in the patient populations studied using the methodology employed.