DynamX Bioadaptor, a novel "uncaging" platform for coronary artery revascularization: final 36-month clinical results

BACKGROUND Compared with bare-metal stents, drug-eluting stents (DES) reduce major adverse cardiac events (MACE) in the first year after percutaneous coronary intervention (PCI) but still have an ongoing 2% to 3% annual event rate reaching 20% at 5 years and 40% to 50% at 10 years. The DynamX Novolimus-Eluting Coronary Bio adaptor System is a 71-mm, cobalt-chromium platform with a novel "uncaging" mechanism of circumferential rings that maintains the axial links between the rings following uncaging. Conventional metallic DES "cage" the coronary artery, inhibiting positive adaptive remodeling and vasomotion and causing geometric distortion. These factors likely contribute to the persistent annual MACE rate after PCI. The DynamX Bioadaptor combines the acute performance of contemporary DES and unique benefits of arterial "uncaging" beyond 6 months, allowing positive adaptive remodeling, restoring compli ance, and allowing treated vessels to return toward native vessel geometry. METHODS In this study the DynamX Bioadaptor was available in di ameters of 2.5 to 3.5 mm and lengths of 14 to 28 mm. This mechanistic clinical study enrolled 50 patients (mean age 66.3 8.8 years) at 5 centers in Belgium and Italy. Multiple endpoints including target lesion failure were assessed, with clinical follow-up through 3 years. Multimodality imaging endpoint analyses using quantitative coronary angiography, intravascular ultrasound, and optical coherence to mography were performed at baseline and at 9 or 12 months in separate subgroups. RESULTS Mean area changes for Bioadaptor, reference vessel and lumen as well as percentage neointimal volume and neointimal thickness observed at 9 and 12 months demonstrate Bioadaptor per formance and ability to preserve positive adaptive remodeling. Through 24 months, target lesion failure events were observed in 4.3% of patients, which is in line with contemporary DES clinical outcomes. Detailed imaging and final clinical data through 36 months will be presented. CONCLUSION The DynamX Bioadaptor demonstrated performance attributes of contemporary metallic DES with the unique capacity to restore positive adaptive remodeling through vessel "uncaging." Final clinical data through 36 months demonstrate longer term safety and efficacy.

Duration of dual antiplatelet therapy in patients with CKD and drug-eluting stents: a meta analysis

Background and objectives Whether prolonged dual antiplatelet therapy (DAPT) is more protective in patients with CKD and drug elutings tents compared with shorter DAPT isuncertain.The purposeofthismeta-analysis was to examine whether shorter DAPT in patients with drug-eluting stents and CKD is associated with lower mortality or major adverse cardiovascular event rates compared with longer DAPT. Design, setting, participants, & measurements A Medline literature research was conducted to identify randomized trials in patients with drug-eluting stents comparing different DAPT duration strategies.Inclusionof patients with CKD was alsorequired. The primary outcome was acomposite of all-cause mortality, myocardial infarction,stroke,orstent thrombosis (definiteorprobable).Major bleeding was the secondary outcome.Therisk ratio (RR) was estimated using a random-effects model. Results Five randomized trials were included (1902 patient swith CKD).Short DAPT (#6months) was associated with a similar incidence of the primary outcome, compared with 12-month DAPT among patients with CKD (48 versus 50 events; RR, 0.93; 95% confidence interval [95% CI], 0.64 to 1.36; P=0.72). Twelve-month DAPT was also associated with a similar incidence of the primary outcome compared with extended DAPT ($30 months) in the CKD subgroup (35 versus 35 events; RR, 1.04; 95% CI, 0.67 to 1.62; P=0.87). Numerically lower major bleeding eventrates were detected with shorter versus 12-monthDAPT(9versus13events;RR,0.69;95%CI,0.30 to1.60;P=0.39)and12-month versus extended DAPT( 9 versus 12 events;RR,0.83;95%CI,0.35to1.93;P=0.66)in patients with CKD.Conclusions Short DAPT does not appear to be inferior to longer DAPT in patients with CKD and drug-eluting stents.Because of imprecisioninestimates (feweventsandwide confidence intervals),nodefinite conclusion scan be drawn with respect to stent thrombosis. (AU)

Clinical, Angiographic, and Procedural Correlates of Very Late Absorb Scaffold Thrombosis: Multistudy Registry Results

OBJECTIVES: The aim of this study was to identify independent correlates of very late scaffold thrombosis (VLST) from an analysis of consecutively treated patients from 15 multicenter studies. BACKGROUND: Recent analyses suggest an increased risk for VLST with the Absorb Bioresorbable Vascular Scaffold compared with drug-eluting stents, but insights as to correlates of risk are limited. METHODS: A total of 55 patients were identified with scaffold thrombosis. They were matched 2:1 with control subjects selected randomly from patients without thrombosis from the same study. Quantitative coronary angiography was available for 96.4% of patients. Multiple logistic and Cox regression analysis were used to identify significant independent outcome correlates from 6 pre-specified characteristics. RESULTS: Patients had scaffold thrombosis at a median of 20 months (interquartile range: 17 to 27 months). Control subjects were followed for 36 months (interquartile range: 24 to 38 months). For the combined groups, reference vessel diameter (RVD) was 2.84 0.50 mm, scaffold length was 26 16 mm, and post-dilatation was performed in56%. Univariate correlates of thrombosis were smaller nominal scaffold/RVD ratio (linear p»0.001; ratio<1.18:1; odds ratio: 7.5; p»0.002) and larger RVD (linear p»0.001;>2.72 mm; odds ratio: 3.4; p»0.001). Post-dilatation at$16 atm, post-dilatation balloon/scaffold ratio, final percentage stenosis, and dual antiplatelet therapy were not correlated with VLST. Only scaffold/RVD ratio remained a significant independent correlate of VLST (p»0.001), as smaller ratio was correlated with RVD (p<0.001). Post hoc analysis of 8 other potential covariates revealed no other correlates of outcome. CONCLUSIONS: In the present analysis, the largest to date of its type, relative scaffold undersizing was the strongest determinant of VLST. Given current understanding of "scaffold dismantling," this finding likely has ramifications for all bioresorbable scaffolds.

Clinical, angiographic, and procedural correlates of acute, subacute, and late absorb scaffold thrombosis

OBJECTIVES: The authors sought to identify and verify independent correlates of device thrombosis from an analysis of multicenter trials and registries. BACKGROUND: Recent analyses suggest an increased risk of device thrombosis with Absorb bioresorbable vascular scaffold (Abbott Vascular, Santa Clara, California) implantation compared with metallic drug-eluting stents, and data from moderate size studies suggest a risk relationship to vessel size and technique. METHODS: From 8,771 consecutively treated patients, 105 patients (1.2%) were identified with scaffold thrombosis within 1 year of implantation. They were matched 2:1 with controls selected randomly from nonthrombosis patients. Data-restricted multiple logistic analysis was used to identify significant independent covariates of the outcome. RESULTS: Early (within 1 month) scaffold thrombosis occurred in 69 patients and late (1 to 12 months) thrombosis occurred in 36 patients. Modelling found significant correlations of thrombosis to be final minimal lumen diameter 1.1:1 balloon/scaffold ratio (OR: 2.3; p = 0.022), and reference vessel diameter <2.40 mm (OR: 2.1; p = 0.036).CONCLUSIONS:Suboptimal vessel sizing, procedural technique, angiographic outcomes, and dual antiplatelet therapy discontinuation appear to be the principal determinants of Absorb scaffold thrombosis risk through 12 months after implantation.

Efficacy and Safety of the Absorb Everolimus-Eluting Bioresorbable Scaffold for Treatment of Patients With Diabetes Mellitus: Results of the Absorb Diabetic Substudy

OBJECTIVES The study sought to evaluate the efficacy and safety of the Absorb everolimus-eluting bioresorbable vascular scaffold (BVS) (Abbott Vascular, Abbott Park, Illinois) in patients with diabetes mellitus.BACKGROUND Randomized, controlled trials have demonstrated comparable clinical outcomes following percutaneous coronary intervention with either Absorb BVS or metallic Xience everolimus-eluting stent. However, these trials lack power required to provide reliable treatment effect estimates in this high-risk population.METHODS In a pre-specified, powered analysis, patients with diabetes who received $1 Absorb were pooled from the ABSORB II, III, and JAPAN randomized trials and from the single arm ABSORB EXTEND registry. The study composite primary endpoint was target lesion failure (TLF) at 1 year following Absorb BVS compared with a performance goal of 12.7%.RESULTS Among 754 diabetic patients included in analysis (27.3% insulin treated), the 1-year TLF rate was8.3% (upper 1-sided 95% confidence limit: 10.1%; p » 0.0001 vs. performance goal). Scaffold thrombosis(definite or probable) was observed in 2.3% of patients. Multivariable regression identified older age, insulin treatment, and smaller pre-procedure reference vessel diameter as significant independent predictors of 1-year TLF.CONCLUSIONS The Absorb diabetic substudy suggests efficacy and safety of the Absorb BVS for treatment of patients with diabetes mellitus.