Dokter Luc Janssens Imeldaziekenhuis Bonheiden Elewijt, 21 september 2013 Bioresorbable Vascular Scaffolds: A New Paradigm in the Treatment of Coronary Artery Disease 1977 1988 2001 - 2003 Andreas Gruntzig performs the first PTCA in Zurich, Switzerland Julio Palmaz and Richard Schatz develop a stainless steel stent for coronary applications Drug eluting stents are introduced to the European and U.S. markets Researchers develop early concepts of bioresorbable devices aimed1977 at Balloon functioning as a temporary scaffold in the coronary Angioplasty vessel (PTCA) 1983 Japanese researchers Bare implant bioresorbable PLLA scaffold in human coronary Metal Stents arteries (Igaki-Tamai device) (BMS) 1999 Abbott Vascular enrolls 30 patients in ABSORB, the first Coronary Drug ever human clinical trial Abbott Vascular a fully bioresorbable establishes the BVS Eluting testing Stents drug eluting scaffold development team 2003 (DES) 2006 The idea for developing a temporary coronary scaffold began in the 1980s 1977 2000 A.B. ,the 1st PTCA by Andreas Gruentzig on September 29, 1977, attended and spoke at the 30th Anniversary on September 30, 2007 in Zurich, an incredible tribute to the breakthrough made by Andreas 30 years ago1 In patients who did not suffer sub-acute closure due to dissections, or restenosis due to negative remodeling in the first few months, long term results following balloon angioplasty were very encouraging and durable, with loss in MLD not seen until 17 years post procedure2 1. Meier, B., N Engl J Med. 2001; 344: 144-145. 2. Hatrick, R., et al. EuroIntervention. 2009;5:121-126. Success of early PCI treatment (POBA) has been demonstrated for as long as 17 yearsx Long-term POBA Serial Angiography Studies 1977 3 (mm) MLD (mm) MLD 2.5 2 1.5 * Guiteras Val Hatrick 2000 1 0.5 0 Meier, B., N Engl J Med. 2001; 344: 144-145 POBA is limited by acute recoil, sub-acute closure, and dissections Guiteras-Val, P., et al. Am J Cardiol. 1999;83:868-874. / Hatrick, R., et al. EuroIntervention. 2009;5:121-126. Rationale Vessel scaffolding is only needed transiently* Vision Improve Long Term Outcomes for Patients by Leaving No Scaffold Behind1 Potential Benefits Restore the vessel to a more natural state, capable of natural vascular function Eliminate chronic sources of vessel irritation and inflammation Vessels remain free for future treatment options Reduce the need for prolonged DAPT2 Allows for use of non-invasive imaging techniques (CCTA) Improve patient quality of life *Serruys PW, et al., Circulation 1988; 77: 361. Serial study suggesting vessels stabilize 3-4 months following PTCA. 1 – Small platinum markers at scaffold edges remain for fluoroscopic landmarking. 2. The Absorb IFU indicates DAPT for a minimum of 6 months. Delayed Healing Stent Thrombosis? * uncovered struts1 Benign NIH Neo-Atheroma Stent Thrombosis? In-Stent Restenosis Late Acquired Malapposition Stent Thrombosis? 1. Virmani, R. Tissue responses in pre-clinical models; CIT 2010 NIH: NeoIntimal Hyperplasia Benign NIH Expansive Remodeling1 In-Scaffold Restenosis Plaque Regression2 Late Lumen Gain Since struts disappear, issues related to very late persistent strut malapposition and chronically uncovered struts become irrelevant 1Serruys, PW, ABSORB Cohort B 1-year results; ACC 2011 / 2Serruys, PW, et al. Lancet. 2009; 373: 897-910. *Small platinum markers at scaffold edges remain for fluoroscopic landmarking. NIH: NeoIntimal Hyperplasia Rationale Vessel scaffolding is only needed transiently* Vision Improve Long Term Outcomes for Patients by Leaving No Scaffold Behind1 Potential Benefits Restore the vessel to a more natural state, capable of natural vascular function Eliminate chronic sources of vessel irritation and inflammation Vessels remain free for future treatment options Reduce the need for prolonged DAPT2 Allows for use of non-invasive imaging techniques (CCTA) Improve patient quality of life *Serruys PW, et al., Circulation 1988; 77: 361. Serial study suggesting vessels stabilize 3-4 months following PTCA. 1 – Small platinum markers at scaffold edges remain for fluoroscopic landmarking. 2. The Absorb IFU indicates DAPT for a minimum of 6 months. Water in surrounding vascular cells and blood penetrates polymer matrix Long polymer chains become shorter and shorter Tie chains Initially, hydrolysis preferentially cleaves amorphous tie chains, leading to a decrease in molecular weight without altering radial strength When enough tie chains are broken, the device begins losing radial strength Support Molecular Weight Mass Loss 1 3 6 12 18 24 Months Resorption Site Absorb BVS 1 month Polymer is replaced by an increasingly cellular provisional matrix 6 months 12 months 24 months XIENCE V Representative photomicrographs of porcine coronary arteries, 2x, Movat’s pentachrome Images on file with Abbott Vascular 30 months 36 months 42 months Resorption Site Absorb BVS 1 month 6 months Polymer is replaced by an increasingly cellular provisional matrix 12 months 24 months 30 months XIENCE V Representative photomicrographs of porcine coronary arteries, 20x, Hematoxylin and Eosin Images on file with Abbott Vascular 36 months 42 months Absorb provides better conformability compared to metallic platforms 88° 91° Absorb BVS Serruys, PW. , Seeing is believing: the clinical evidence so far; PCR 2010; J. Gomez-Lara, JACC Cardiovascular Interventions. 2010; 3: 1190-8. 12 Months2 24 Months3 ABSORB Cohort B1 ABSORB Cohort B2 ABSORB Cohort A (N=15) (N=6) (N=19) (N=13) (N=9) 0.5 (N=7) Vasodilation 6 Months1 0 -0.5 Acetylcholine -1 Vasoconstriction in Vessel Diameter (mm) (pre-drug infusion to post-drug infusion) 1 Methergine 1. Adapted from Serruys, PW. ACC 2011 / 2. Adapted from Serruys, PW. ACC 2011 / 3. Adapted from Serruys, PW, et al. Lancet 2009; 373: 897-910. Post-PCI 6 Months n = 33 n = 33 ABSORB Cohort B Serial Analysis* Lumen Area 6.53 mm2 Scaffold Area 1.7% 6.36 mm2 n = 33 6.85 mm2 Lumen Area 7.2% Late Loss = 0.19 mm *Serruys, PW., TCT 2011 2 Years There is still room for improvement Serruys, PW. PCR 2010 Serruys, PW. PCR 2010 Intent to Treat (ITT) Analysis – Interim Snapshot The datasets are from different trials and displayed for descriptive purposed only. MACE: a composite of cardiac death, MI, and ischemia-driven TLR Chevalier, ABSORB EXTEND 12-month outcomes in the first 450 patient enrolled, Rotterdam EuroPCR Focus on BVS 2013 Rationale Vessel scaffolding is only needed transiently* Vision Improve Long Term Outcomes for Patients by Leaving No Scaffold Behind1 Potential Benefits Restore the vessel to a more natural state, capable of natural vascular function Eliminate chronic sources of vessel irritation and inflammation Vessels remain free for future treatment options Reduce the need for prolonged DAPT2 Allows for use of non-invasive imaging techniques (CCTA) Improve patient quality of life *Serruys PW, et al., Circulation 1988; 77: 361. Serial study suggesting vessels stabilize 3-4 months following PTCA. 1 – Small platinum markers at scaffold edges remain for fluoroscopic landmarking. 2. The Absorb IFU indicates DAPT for a minimum of 6 months. Patients at risk for future interventions Young patients may need future Bioresorbable vascular scaffolds will interventions that can be complicated preserve more treatment options for or compromised by a permanent implant future interventions First time, young patients* Non-invasive assessment of patients by MSCT Non-invasive imaging for early and late followup is feasible with BVS Patients with metal allergy Population with nickel allergy is estimated to be 8.6% of the general population1 Allergic reactions to nickel and molybdenum released from stents may be one of the triggering mechanisms for in-stent restenosis2 *Young patient defined as <65 years of age / 1. Thyssen et al. Contact Dermatitis 2007 / 2. Koster, Lancet, Vol 356, 12/2/00