Author + information
- Received December 22, 2015
- Accepted January 15, 2016
- Published online April 25, 2016.
- Shimpei Nakatani, MDa,
- Yuki Ishibashi, MD, PhDa,
- Yohei Sotomi, MDb,
- Laura Perkins, DVM, PhDc,
- Jeroen Eggermont, PhDd,
- Maik J. Grundeken, MDb,
- Jouke Dijkstra, PhDd,
- Richard Rapoza, PhDc,
- Renu Virmani, MDe,
- Patrick W. Serruys, MD, PhDf and
- Yoshinobu Onuma, MD, PhDa,∗ ()
- aThoraxCenter, Erasmus Medical Center, Rotterdam, the Netherlands
- bAcademic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- cAbbott Vascular, Santa Clara, California
- dLeiden University Medical Center, Leiden, the Netherlands
- eCVPath Institute, Gaithersburg, Maryland
- fInternational Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, London, United Kingdom
- ↵∗Reprint requests and correspondence:
Dr. Yoshinobu Onuma, Thoraxcenter, Ba-583, ’s Gravendijkwal 230, 3015 CE Rotterdam, the Netherlands.
Objectives The aim of the present study was to investigate the relationship between the integration process and luminal enlargement with the support of light intensity (LI) analysis on optical coherence tomography (OCT), echogenicity analysis on intravascular ultrasound, and histology up to 4 years in a porcine model.
Background In pre-clinical and clinical studies, late luminal enlargement has been demonstrated at long-term follow-up after everolimus-eluting poly-l-lactic acid coronary scaffold implantation. However, the time relationship and the mechanistic association with the integration process are still unclear.
Methods Seventy-three nonatherosclerotic swine that received 112 Absorb scaffolds were evaluated in vivo by OCT, intravascular ultrasound, and post-mortem histomorphometry at 3, 6, 12, 18, 24, 30, 36, 42, and 48 months.
Results The normalized LI, which is the signal densitometry on OCT of a polymeric strut core normalized by the vicinal neointima, was able to differentiate the degree of connective tissue infiltration inside the strut cores. Luminal enlargement was a biphasic process at 6 to 18 months and at 30 to 42 months. The latter phase occurred with vessel wall thinning and coincided with the advance integration process demonstrated by the steep change in normalized LI (0.26 [interquartile range (IQR): 0.20 to 0.32] at 30 months versus 0.68 [IQR: 0.58 to 0.83] at 42 months, p < 0.001).
Conclusions In this pre-clinical model, late luminal enlargement relates to strut integration into the arterial wall. Quantitative LI analysis on OCT could be used as a surrogate method for monitoring the integration process of poly-l-lactic acid scaffolds, which could provide insight and understanding on the imaging-related characteristics of the bioresorption process of polylactide scaffolds in human.
- biodegradable polymer
- bioresorbable scaffold
- coronary intervention
- intravascular ultrasound
- optical coherence tomography
This study was funded by Abbott Vascular. Drs. Perkins and Rapoza are full-time employees of Abbott Vascular. Drs. Serruys and Onuma are members of the advisory board of Abbott Vascular. Dr Virmani receives research support from Abbott Vascular, BioSensors International, Biotronik, Boston Scientific, Medtronic, MicroPort Medical, OrbusNeich Medical, SINO Medical Technology, and Terumo Corporation; has speaking engagements with Merck; receives honoraria from Abbott Vascular, Boston Scientific, Lutonix, Medtronic, and Terumo Corporation; and is a consultant for 480 Biomedical, Abbott Vascular, Medtronic, and W.L. Gore. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received December 22, 2015.
- Accepted January 15, 2016.
- 2016 American College of Cardiology Foundation