Serial analysis of the malapposed and uncovered struts of the new generation of everolimus-eluting bioresorbable scaffold with optical coherence tomography.

OBJECTIVES The aim of this study is to assess the serial changes in strut apposition and coverage of the bioresorbable vascular scaffolds (BVS) and to relate this with the presence of intraluminal masses at 6 months with optical coherence tomography (OCT). BACKGROUND Incomplete strut/scaffold apposition (ISA) and uncovered struts are related to a higher risk of scaffold thrombosis. Bioresorbable vascular scaffolds can potentially avoid the risk of scaffold thrombosis because of its complete resorption. However, during the resorption period, the risk of scaffold thrombosis is unknown. METHODS OCT was performed in 25 patients at baseline and 6 months. Struts were classified according to apposition, coverage, and presence of intraluminal masses. Persistent ISA was defined as malapposed struts present at baseline and follow-up, and late acquired ISA as ISA developing at follow-up, and scaffold pattern irregularities when the strut distribution suggested scaffold fracture. RESULTS At baseline, 3,686 struts were analyzed: 128 (4%) were ISA, and 53 (1%) were located over side-branches (SB). At 6 months, 3,905 struts were analyzed: 32 (1%) ISA, and 35 (1%) at the SB. Persistent ISA was observed more frequently than late acquired-ISA (81% vs. 16%, respectively; 3% were unmatchable). Late acquired ISA was associated with scaffold pattern irregularities, which were related to overstretching of the scaffold. Uncovered struts (63 struts, 2%) were more frequently observed in ISA and SB struts, compared with apposed struts (29% vs. 1%; p < 0.01). Intraluminal masses (14 cross-sections, 3%; in 6 patients, 24%) were more frequently located at the site of ISA and/or uncovered struts (39% vs. 2% and 13% vs. 2%, respectively; p < 0.01). CONCLUSIONS The lack of strut apposition at baseline is related to the presence of uncovered struts and intraluminal masses at 6 month. An appropriate balloon/artery ratio respecting the actual vessel size and avoiding the overstretching of the scaffold can potentially decrease the risk of scaffold thrombosis. (ABSORB Clinical Investigation, Cohort B [ABSORB B).

[1]  Hiromasa Otake,et al.  Neointimal coverage of sirolimus-eluting stents at 6-month follow-up: evaluated by optical coherence tomography. , 2007, European heart journal.

[2]  P. Serruys,et al.  Incomplete Stent Apposition After Implantation of Paclitaxel-Eluting Stents or Bare Metal Stents: Insights From the Randomized TAXUS II Trial , 2005, Circulation.

[3]  M. Takano,et al.  Advanced neointimal growth is not associated with a low risk of in-stent thrombus. Optical coherence tomographic findings after first-generation drug-eluting stent implantation. , 2009, Circulation journal : official journal of the Japanese Circulation Society.

[4]  P. Fitzgerald,et al.  Effect of everolimus-eluting stents in different vessel sizes (from the pooled FUTURE I and II trials). , 2006, The American journal of cardiology.

[5]  Jacob Cohen.  A Coefficient of Agreement for Nominal Scales , 1960 .

[6]  H. Toutenburg.  Fleiss, J. L.: Statistical Methods for Rates and Proportions. John Wiley & Sons, New York‐London‐Sydney‐Toronto 1973. XIII, 233 S. , 1974 .

[7]  Bernard Chevalier,et al.  Evaluation of the Second Generation of a Bioresorbable Everolimus Drug-Eluting Vascular Scaffold for Treatment of De Novo Coronary Artery Stenosis: Six-Month Clinical and Imaging Outcomes , 2010, Circulation.

[8]  J. Tanigawa,et al.  Optical coherence tomography to assess malapposition in overlapping drug-eluting stents. , 2008, EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology.

[9]  Y. Jang,et al.  Evaluation in 3 months duration of neointimal coverage after zotarolimus-eluting stent implantation by optical coherence tomography: the ENDEAVOR OCT trial. , 2009, JACC. Cardiovascular interventions.

[10]  K. Hirata,et al.  Delayed neointimalization on sirolimus-eluting stents: 6-month and 12-month follow up by optical coherence tomography. , 2009, Circulation journal : official journal of the Japanese Circulation Society.

[11]  P. Fitzgerald,et al.  Comparison of vascular response to zotarolimus-eluting stent versus sirolimus-eluting stent: intravascular ultrasound results from ENDEAVOR III. , 2008, American heart journal.

[12]  J. Tanigawa,et al.  The influence of strut thickness and cell design on immediate apposition of drug-eluting stents assessed by optical coherence tomography. , 2009, International journal of cardiology.

[13]  R. Virmani,et al.  Pathological Correlates of Late Drug-Eluting Stent Thrombosis: Strut Coverage as a Marker of Endothelialization , 2007, Circulation.

[14]  Late incomplete stent apposition after sirolimus-eluting stent implantation: a serial intravascular ultrasound analysis. , 2005, Journal of the American College of Cardiology.

[15]  E. Halpern,et al.  Evaluation of intracoronary stenting by intravascular optical coherence tomography , 2003, Heart.

[16]  Hiromasa Otake,et al.  Local determinants of thrombus formation following sirolimus-eluting stent implantation assessed by optical coherence tomography. , 2009, JACC. Cardiovascular interventions.

[17]  Giuseppe Biondi-Zoccai,et al.  Optical coherence tomography assessment of in vivo vascular response after implantation of overlapping bare-metal and drug-eluting stents. , 2010, JACC. Cardiovascular interventions.

[18]  Patrick W Serruys,et al.  A comparative assessment by optical coherence tomography of the performance of the first and second generation of the everolimus-eluting bioresorbable vascular scaffolds. , 2011, European heart journal.

[19]  Patrick W Serruys,et al.  A bioabsorbable everolimus-eluting coronary stent system for patients with single de-novo coronary artery lesions (ABSORB): a prospective open-label trial , 2008, The Lancet.

[20]  P. Serruys,et al.  The fate of incomplete stent apposition with drug-eluting stents: an optical coherence tomography-based natural history study. , 2010, European heart journal.

[21]  Michael Joner,et al.  Pathology of drug-eluting stents in humans: delayed healing and late thrombotic risk. , 2006, Journal of the American College of Cardiology.

[22]  Yoshinobu Onuma,et al.  In vivo evaluation of stent strut distribution patterns in the bioabsorbable everolimus-eluting device: An OCT ad hoc analysis of the revision 1.0 and revision 1.1 stent design in the ABSORB clinical trial , 2010 .

[23]  Patrick W Serruys,et al.  A bioabsorbable everolimus-eluting coronary stent system (ABSORB): 2-year outcomes and results from multiple imaging methods , 2009, The Lancet.

[24]  Yoshinobu Morikawa,et al.  Long-term follow-up of neointimal coverage of sirolimus-eluting stents--evaluation with optical coherence tomography. , 2009, Circulation journal : official journal of the Japanese Circulation Society.

[25]  P. Serruys,et al.  Long-Term Follow-Up of Incomplete Stent Apposition in Patients Who Received Sirolimus-Eluting Stent for De Novo Coronary Lesions: An Intravascular Ultrasound Analysis , 2003, Circulation.

[26]  M. Costa,et al.  Intravascular ultrasound, angioscopic and histopathological characterisation of heterogeneous patterns of restenosis after sirolimus-eluting stent implantation: insights into potential "thromborestenosis" phenomenon. , 2010, EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology.

[27]  Seung‐Jung Park,et al.  Late Stent Malapposition After Drug-Eluting Stent Implantation: An Intravascular Ultrasound Analysis With Long-Term Follow-Up , 2006, Circulation.

[28]  Rolf Vogel,et al.  Incomplete Stent Apposition and Very Late Stent Thrombosis After Drug-Eluting Stent Implantation , 2007, Circulation.

[29]  R. Whitbourn,et al.  Comparison between the first and second generation bioresorbable vascular scaffolds: a six month virtual histology study. , 2011, EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology.

[30]  J. Fleiss.  Statistical methods for rates and proportions , 1974 .

[31]  Takashi Akasaka,et al.  Comparison of vascular response after sirolimus-eluting stent implantation between patients with unstable and stable angina pectoris: a serial optical coherence tomography study. , 2008, JACC. Cardiovascular imaging.

[32]  Bernard Chevalier,et al.  Evaluation of the second generation of a bioresorbable everolimus-eluting vascular scaffold for the treatment of de novo coronary artery stenosis: 12-month clinical and imaging outcomes. , 2011, Journal of the American College of Cardiology.