APPOSITION V: STENTYS coronary stent system clinical trial in subjects with ST-segment elevation myocardial infarction—Rationale and design Maik J. Grundeken, MD, a,l Huangling Lu, MD, a,l Roxana Mehran, MD, b Donald E. Cutlip, MD, c,d Martin B. Leon, MD, e,f Alan Yeung, MD, g Karel T. Koch, MD, PhD, a Gilles Montalescot, MD, PhD, h Robert-Jan van Geuns, MD, PhD, i René Spaargaren, MD, j and Maurice Buchbinder, MD k Amsterdam, Rotterdam, the Netherlands; New York, NY; Boston, MA; Palo Alto, CA; Paris, France; and La Jolla, CA Background Primary percutaneous coronary intervention (PCI) has considerably improved clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) when compared with thrombolytic therapy. Prognosis after primary PCI might be further improved by decreasing stent-related complications such as stent thrombosis. The STENTYS self-apposing stent has been shown to be superior compared with balloon-expandable stents with regard to stent apposition. The current prospective randomized trial was designed to evaluate whether the superior stent apposition of the STENTYS stent results in clinical outcomes that are at least noninferior to a conventional balloon-expandable stent. Methods The APPOSITION V is a prospective, multicenter, international, single-blinded, randomized controlled trial in STEMI patients. Randomization will be performed in a 2:1 ratio between the self-apposing nitinol bare-metal STENTYS stent and the balloon-expandable bare-metal MULTI-LINK. The primary end point is defined as target vessel failure, which is a composite of cardiac death, target vessel–related recurrent myocardial infarction, or clinically driven target vessel revascularization, at 1-year follow-up. Baseline intravascular ultrasound and optical coherence tomography (OCT) substudies will be performed in 212 and 60 subjects, respectively, and a repeat angiography at 12 to 13 months will be performed in 105 subjects, including intravascular ultrasound and OCT (in the 60 OCT patients). This study is registered on ClinicalTrials. gov with number NCT01732341. Conclusion APPOSITION V will be the first randomized trial powered on clinical end points that directly compares the STENTYS self-apposing stent with a conventional balloon-expandable stent in patients presenting with STEMI undergoing primary PCI. (Am Heart J 2014;168:652-660.e2.) The preferred therapy to treat patients with ST-segment elevation myocardial infarction (STEMI) is primary percutaneous coronary intervention (PCI), based on randomized data consistently showing superiority of this approach over thrombolytic therapy regarding cardiac and all-cause mortality rates. 1 However, prognosis after primary PCI is still worse when compared with elective PCI. 2 This is partly explained by the natural course of acute myocardial infarction (MI), including necrosis, as well as fibrosis of this necrotic myocardial tissue, leading to impaired ventricular function and the occurrence of lethal arrhythmias. Prognosis after STEMI is also determined by complications related to the primary PCI itself, such as stent thrombosis (ST) and distal embolization of plaque debris and/or thrombotic material. 3,4 One of the contributing factors for the occurrence of ST is incomplete stent apposition, 5,6 which is assumed to be associated with ST due to delayed strut coverage of the incompletely apposed struts. 7 Several studies have found that incomplete stent apposition occurs more often in the setting of primary PCI compared with elective PCI when using conventional balloon-expandable stents, 8,9 although some studies did not find this relation. 10 Acute stent malapposition (ASM) is related to the presence of thrombus, hampering adequate estimation of the diameter From the a Heartcenter, Academic Medical Center-University of Amsterdam, Amsterdam, the Netherlands, b Mount Sinai Hospital, New York, NY, c Beth Israel Deaconess Medical Center, Boston, MA, d Harvard Clinical Research Institute, Boston, MA, e Columbia University Medical Center/New York Presbyterian, New York, NY, f Cardiovascular Research Foundation, New York, NY, g Stanford University School of Medicine, Palo Alto, CA, h CHU La Pitié-Salpêtrière (AP-HP), Paris, France, i Thoraxcenter, Erasmus Medical Center, Rotterdam, the Netherlands, j STENTYS S.A., Paris, France, and k Foundation for Cardiovascular Medicine, La Jolla, CA. l Both authors contributed equally. Submitted March 16, 2014; accepted July 18, 2014. Reprint requests: Roxana Mehran, MD, Health Evidence and Policy, Icahn School of Medicine at Mount Sinai, One Gustave L Levy Place, Box 1030, New York, NY 10029. E-mail: roxana.mehran@mountsinai.org 0002-8703 © 2014 Published by Elsevier Inc. http://dx.doi.org/10.1016/j.ahj.2014.07.011