Vasomotor Response to Nitroglycerine Over 5 Years Follow-Up After Everolimus-Eluting Bioresorbable Scaffold Implantation.

OBJECTIVES: This study investigated the vasomotor response to nitroglycerine (NTG) up to 5 years after ABSORB implantation. BACKGROUND: There are no data regarding long-term vasomotor response after everolimus-eluting bioresorbable vascular scaffold ABSORB implantation. METHODS: We performed quantitative coronary angiography of the scaffolded and proximal and distal adjacent segments of patients from ABSORB Cohort B study before and after 200 µg of intracoronary NTG at 2, 3, and 5 years of follow-up. The mean changes of maximal and mean lumen diameters in the scaffolded and adjacent segments were calculated. RESULTS: The mean in-scaffold lumen diameter change in response to NTG showed a trend to increase over time with absolute values of 0.03 ± 0.09 mm, 0.05 ± 0.12 mm, and 0.07 ± 0.08 mm at 2, 3, and 5 years, respectively (p = 0.40). The maximal in-scaffold lumen diameter change significantly increased with values of 0.03 ± 0.14 mm, 0.06 ± 0.16 mm, and 0.11 ± 0.1 mm at 2, 3, and 5 years, respectively (p = 0.03). The normalized mean lumen diameter change after NTG in the scaffold relative to the adjacent segments was 51.9 ± 54.8% at 5 years of follow-up (p = 0.60). CONCLUSIONS: Although there was a numerical increase of the vasomotor response to NTG after ABSORB implantation measured by quantitative coronary angiography with mean lumen diameter, the change was not statistically significant. However, the maximal lumen diameter changes increased over time from 2 to 5 years and attained statistical significance. The vasomotor response to NTG after ABSORB implantation moderately trended to increase, which is consistent with the progressive degradation and bioresorption of the scaffold, but the degree of vasomotor response remained lower in comparison with adjacent segments.

Long-term serial non-invasive multislice computed tomography angiography with functional evaluation after coronary implantation of a bioresorbable everolimus-eluting scaffold: the ABSORB cohort B MSCT substudy.

AIMS: Multimodality invasive imaging of the first-in-man cohort demonstrated at 5 years stable lumen dimensions and a low rate of major adverse cardiac events (MACE). However, the long-term non-invasive assessment of this device remains to be documented. The objective was to describe the 72-month multislice computed tomography (MSCT) angiographic and functional findings after the implantation of the second iteration of the fully resorbable everolimus-eluting polymeric scaffold. METHODS AND RESULTS: In the ABSORB Cohort B trial patients with non-complex de novo lesions were treated with second iteration bioresobable vascular scaffold (BVS). MSCT angiography was performed as an optional investigation at 18 months; patients were reconsented for a second investigation at 72 months. MSCT data were analysed at independent core laboratories for quantitative analysis of lumen dimensions and for calculation of fractional flow reserve derived from computed tomography (FFRCT). From the overall Cohort B (101 patients), 53 patients underwent MSCT imaging at 72 months. The MACE rate was 1.9% (1/53). At 72 months, the median minimal lumen area (MLA) was 4.05 mm2 (interquartile range [IQR]: 3.15-4.90) and the mean percentage area stenosis was 18% (IQR: 4.75-31.25), one scaffold was totally occluded. In 39 patients with paired MSCT analysis, the MLA significantly increased from the first to the second follow-up (Δ = 0.80 mm2, P = 0.002). The change in the median FFRCT scaffold gradient between time points was zero. CONCLUSION: The long-term serial non-invasive MSCT evaluation with FFRCT assessment after bioresorbable scaffold implantation confirmed in-scaffold late lumen enlargement with the persistence of normalization of the FFRCT. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00856856.

Prediction of atherosclerotic disease progression using LDL transport modelling: a serial computed tomographic coronary angiographic study.

AIM: To investigate the efficacy of low-density lipoprotein (LDL) transport simulation in reconstructed arteries derived from computed tomography coronary angiography (CTCA) to predict coronary segments that are prone to progress. METHODS AND RESULTS: Thirty-two patients admitted with an acute coronary event who underwent 64-slice CTCA after percutaneous coronary intervention and at 3-year follow-up were included in the analysis. The CTCA data were used to reconstruct the coronary anatomy of the untreated vessels at baseline and follow-up, and LDL transport simulation was performed in the baseline models. The computed endothelial shear stress (ESS), LDL concentration, and CTCA-derived plaque characteristics were used to identify predictors of substantial disease progression (defined as an increase in the plaque burden at follow-up higher than two standard deviations of the intra-observer variability of the expert who performed the analysis). Fifty-eight vessels were analysed. High LDL concentration [odds ratio (OR): 2.16; 95% confidence interval (CI): 1.64-2.84; P = 0.0054], plaque burden (OR: 1.40; 95% CI: 1.13-1.72; P = 0.0017), and plaque area (OR: 3.46; 95% CI: 2.20-5.44; P≤ 0.0001) were independent predictors of a substantial disease progression at follow-up. The ESS appears as a predictor of disease progression in univariate analysis but was not an independent predictor when the LDL concentration was entered into the multivariate model. The accuracy of the model that included the LDL concentration was higher than the accuracy of the model that included the ESS (65.1 vs. 62.5%). CONCLUSIONS: LDL transport modelling appears a better predictor of atherosclerotic disease progression than the ESS, and combined with the atheroma characteristics provided by CTCA is able to detect with a moderate accuracy segments that will exhibit a significant plaque burden increase at mid-term follow-up.

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 was 8.3% (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.

Edge Vascular Response After Resorption of the Everolimus-Eluting Bioresorbable Vascular Scaffold　- A 5-Year Serial Optical Coherence Tomography Study.

BACKGROUND: The edge vascular response (EVR) has been linked to important prognostic implications in patients treated with permanent metallic stents. We aimed to investigate the relationship of EVR with the geometric changes in the everolimus-eluting bioresorbable scaffold using serial optical coherence tomography (OCT) analysis. METHODS AND RESULTS: In the first-in-man ABSORB trial, 28 patients (29 lesions) underwent serial OCT at 4 different time points (Cohort B1: post-procedure, 6, 24, and 60 months [n=13]; Cohort B2: post-procedure, 12, 36, and 60 months [n=15]) following implantation of the scaffold. In Cohort B1, there was no significant luminal change at the distal or proximal edge segment throughout the entire follow-up. In contrast, there was a significant reduction of the lumen flow area (LFA) of the scaffold between post-procedure and 6 months (-1.03±0.49 mm(2)[P<0.001]), whereas between 6 and 60 months the LFA remained stable (+0.31±1.00 mm(2)[P=0.293]). In Cohort B2, there was a significant luminal reduction of the proximal edge between post-procedure and 12 months (-0.57±0.74 mm(2)[P=0.017]), whereas the lumen area remained stable (-0.26±1.22 mm(2)[P=0.462]) between 12 and 60 months. The scaffold LFA showed a change similar to that observed in Cohort B1. CONCLUSIONS: Our study demonstrated a reduction in the scaffold luminal area in the absence of major EVR, suggesting that the physiological continuity of the lumen contour is restored long term. (Circ J 2016; 80: 1131-1141).

A Polylactide Bioresorbable Scaffold Eluting Everolimus for Treatment of Coronary Stenosis: 5-Year Follow-Up.

BACKGROUND: Long-term benefits of coronary stenosis treatment with an everolimus-eluting bioresorbable scaffold are unknown. OBJECTIVES: This study sought to evaluate clinical and imaging outcomes 5 years after bioresorbable scaffold implantation. METHODS: In the ABSORB multicenter, single-arm trial, 45 (B1) and 56 patients (B2) underwent coronary angiography, intravascular ultrasound (IVUS), and optical coherence tomography (OCT) at different times. At 5 years, 53 patients without target lesion revascularization underwent final imaging. RESULTS: Between 6 months/1 year and 5 years, angiographic luminal late loss remained unchanged (B1: 0.14 ± 19 mm vs. 0.13 ± 0.33 mm; p = 0.7953; B2: 0.23 ± 0.28 mm vs. 0.18 ± 0.32 mm; p = 0.5685). When patients with a target lesion revascularization were included, luminal late loss was 0.15 ± 0.20 mm versus 0.15 ± 0.24 mm (p = 0.8275) for B1 and 0.30 ± 0.37 mm versus 0.32 ± 0.48 mm (p = 0.8204) for B2. At 5 years, in-scaffold and -segment binary restenosis was 7.8% (5 of 64) and 12.5% (8 of 64). On IVUS, the minimum lumen area of B1 decreased from 5.23 ± 0.97 mm(2) at 6 months to 4.89 ± 1.81 mm(2) at 5 years (p = 0.04), but remained unchanged in B2 (4.95 ± 0.91 mm(2) at 1 year to 4.84 ± 1.28 mm(2) at 5 years; p = 0.5). At 5 years, struts were no longer discernable by OCT and IVUS. On OCT, the minimum lumen area in B1 decreased from 4.51 ± 1.28 mm(2) at 6 months to 3.65 ± 1.39 mm(2) at 5 years (p = 0.01), but remained unchanged in B2, 4.35 ± 1.09 mm(2) at 1 year and 4.12 ± 1.38 mm(2) at 5 years (p = 0.24). Overall, the 5-year major adverse cardiac event rate was 11.0%, without any scaffold thrombosis. CONCLUSIONS: At 5 years, bioresorbable scaffold implantation in a simple stenotic lesion resulted in stable lumen dimensions and low restenosis and major adverse cardiac event rates. (ABSORB Clinical Investigation, Cohort B [ABSORB B]; NCT00856856).

Impact of the Everolimus-eluting Bioresorbable Scaffold in Coronary Atherosclerosis.

INTRODUCTION AND OBJECTIVES: The Absorb bioresorbable vascular scaffold has been shown to decrease total plaque areas in the treated segment. However, it is unknown whether plaque size is modified in scaffolded segments only or whether the modification extends to other coronary segments. METHODS: Absorb Cohort A is a single-arm, prospective study, with safety and imaging endpoints, in which 30 patients underwent percutaneous coronary intervention with the first generation Absorb bioresorbable vascular scaffold. Noninvasive multislice computed tomography imaging was performed in 18 patients at 18 months and 5 years of follow-up. The present study was an intrapatient comparison of matched segments (normalized by the segment length) of the scaffolded region with nonintervened segments for lumen volume, vessel volume, plaque volume, plaque burden, and percent change in plaque atheroma volume. RESULTS: All 18 scaffolded segments could be analyzed. In the nonintervened segments, 1 of 72 segments had a motion artifact and was excluded. Serial comparison showed that the scaffolded segments showed no significant change in the mean plaque burden, total atheroma volume, total lumen volume, or vessel volume between 18 months and 5 years. Conversely, the untreated segments showed a significant increase in plaque burden (2.7 ± 6.5%; P < .01) and normalized plaque volumes (8.0 ± 22.8mm(3); P < .01). This resulted in a significant difference in plaque burden between scaffolded and nonintervened segments (P = .03). CONCLUSIONS: In this small series, the Absorb bioresorbable vascular scaffold showed the potential to provide an additional benefit to pharmacological therapy in locally reducing progression of percent plaque burden. These findings need to be confirmed in larger studies.

The incidence and relevance of site-reported vs. patient-reported angina: insights from the ABSORB II randomized trial comparing Absorb everolimus-eluting bioresorbable scaffold with XIENCE everolimus-eluting metallic stent.

AIMS: In the ABSORB II trial, comparing Absorb™ bioresorbable vascular scaffold with metallic XIENCE™ everolimus-eluting stent (EES), a difference was found in site-reported new or worsening angina using adverse event (AE) reporting. However, the clinical relevance of this site-reported angina is unclear. The aim of the present study was therefore to investigate the clinical relevance of site-reported angina by evaluating its relation with cardiac endpoints, cardiovascular resource utilization (including diagnostics and treatment), positive exercise stress tolerance tests (ETTs), and Seattle Angina Questionnaire (SAQ). METHODS AND RESULTS: Site-reported new or worsening angina was captured on cardiac AE forms. There was a wide variation in the total number of days with site-reported angina (overall interquartile range 35-279 days). Patients with site-reported angina showed higher rates of cardiovascular events [including the patient-oriented composite endpoint of all deaths, all myocardial infarctions (MI), or all revascularizations (21.1 vs. 4.2%, P < 0.0001), all MIs (2.3 vs. 0%, P = 0.03), and all revascularizations (21.1 vs. 0.7%, P < 0.0001)], cardiovascular resource utilization (including stress tests, anti-anginal medication, diagnostic angiographies, and hospitalization), and positive ETTs (51.9 vs. 14.9%, P < 0.001), compared with those without site-reported angina. Furthermore, an event-based analysis of the SAQ showed that patients with ongoing angina within the recall period of 4 weeks prior to the SAQ assessment have clinically and statistically significant decrements of >14 points in SAQ scores compared with those with no reported angina. CONCLUSIONS: We showed that the site-reported angina through AE reporting may be clinically relevant because of their relation with cardiovascular events (mostly repeat revascularizations), cardiovascular resource utilization, ETT, and SAQ. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT01425281; Unique identifier: NCT01425281.

Relation Between Bioresorbable Scaffold Sizing Using QCA-Dmax and Clinical Outcomes at 1 Year in 1,232 Patients From 3 Study Cohorts (ABSORB Cohort B, ABSORB EXTEND, and ABSORB II).

OBJECTIVES: This study sought to investigate the clinical outcomes based on the assessment of quantitative coronary angiography-maximal lumen diameter (Dmax). BACKGROUND: Assessment of pre-procedural Dmax of proximal and distal sites has been used for Absorb scaffold size selection in the ABSORB studies. METHODS: A total of 1,248 patients received Absorb scaffolds in the ABSORB Cohort B (ABSORB Clinical Investigation, Cohort B) study (N = 101), ABSORB EXTEND (ABSORB EXTEND Clinical Investigation) study (N = 812), and ABSORB II (ABSORB II Randomized Controlled Trial) trial (N = 335). The incidence of major adverse cardiac events (MACE) (a composite of cardiac death, any myocardial infarction [MI], and ischemia-driven target lesion revascularization) was analyzed according to the Dmax subclassification of scaffold oversize group versus scaffold nonoversize group. RESULTS: Of 1,248 patients, pre-procedural Dmax was assessed in 1,232 patients (98.7%). In 649 (52.7%) patients, both proximal and distal Dmax values were smaller than the nominal size of the implanted scaffold (scaffold oversize group), whereas in 583 (47.3%) of patients, the proximal and/or distal Dmax were larger than the implanted scaffold (scaffold nonoversize group). The rates of MACE and MI at 1 year were significantly higher in the scaffold oversize group than in the scaffold nonoversize group (MACE 6.6% vs. 3.3%; log-rank p < 0.01, all MI: 4.6% vs. 2.4%; log-rank p = 0.04), mainly driven by a higher MI rate within 1 month post-procedure (3.5% vs. 1.9%; p = 0.08). The independent MACE determinants were both Dmax smaller than the scaffold nominal size (odds ratio [OR]: 2.13, 95% confidence interval [CI]: 1.22 to 3.70; p < 0.01) and the implantation of overlapping scaffolds (OR: 2.10, 95% CI: 1.17 to 3.80; p = 0.01). CONCLUSIONS: Implantation of an oversized Absorb scaffold in a relatively small vessel appears to be associated with a higher 1-year MACE rate driven by more frequent early MI. (ABSORB Clinical Investigation, Cohort B [ABSORB Cohort B], NCT00856856; ABSORB EXTEND Clinical Investigation [ABSORB EXTEND], NCT01023789; ABSORB II Randomized Controlled Trial [ABSORB II], NCT01425281).

A bioresorbable everolimus-eluting scaffold versus a metallic everolimus-eluting stent for ischaemic heart disease caused by de-novo native coronary artery lesions (ABSORB II): an interim 1-year analysis of clinical and procedural secondary outcomes from a randomised controlled trial.

BACKGROUND: Despite rapid dissemination of an everolimus-eluting bioresorbable scaffold for treatment for coronary artery disease, no data from comparisons with its metallic stent counterpart are available. In a randomised controlled trial we aimed to compare an everolimus-eluting bioresorbable scaffold with an everolimus-eluting metallic stent. Here we report secondary clinical and procedural outcomes after 1 year of follow-up. METHODS: In a single-blind, multicentre, randomised trial, we enrolled eligible patients aged 18-85 years with evidence of myocardial ischaemia and one or two de-novo native lesions in different epicardial vessels. We randomly assigned patients in a 2:1 ratio to receive treatment with an everolimus-eluting bioresorbable scaffold (Absorb, Abbott Vascular, Santa Clara, CA, USA) or treatment with an everolimus-eluting metallic stent (Xience, Abbott Vascular, Santa Clara, CA, USA). Randomisation was stratified by diabetes status and number of planned target lesions. The co-primary endpoints of this study are vasomotion (change in mean lumen diameter before and after nitrate administration at 3 years) and difference between minimum lumen diameter (after nitrate administration) after the index procedure and at 3 years. Secondary endpoints were procedural performance assessed by quantitative angiography and intravascular ultrasound; composite clinical endpoints based on death, myocardial infarction, and coronary revascularisation; device and procedural success; and angina status assessed by the Seattle Angina Questionnaire and exercise testing at 6 and 12 months. Cumulative angina rate based on adverse event reporting was analysed post hoc. This trial is registered at ClinicalTrials.gov, number NCT01425281. FINDINGS: Between Nov 28, 2011, and June 4, 2013, we enrolled 501 patients and randomly assigned them to the bioresorbable scaffold group (335 patients, 364 lesions) or the metallic stent group (166 patients, 182 lesions). Dilatation pressure and balloon diameter at the highest pressure during implantation or postdilatation were higher and larger in the metallic stent group, whereas the acute recoil post implantation was similar (0.19 mm for both, p=0.85). Acute lumen gain was lower for the bioresorbable scaffold by quantitative coronary angiography (1.15 mm vs 1.46 mm, p<0.0001) and quantitative intravascular ultrasound (2.85 mm(2)vs 3.60 mm(2), p<0.0001), resulting in a smaller lumen diameter or area post procedure. At 1 year, however, cumulative rates of first new or worsening angina from adverse event reporting were lower (72 patients [22%] in the bioresorbable scaffold group vs 50 [30%] in the metallic stent group, p=0.04), whereas performance during maximum exercise and angina status by SAQ were similar. The 1-year composite device orientated endpoint was similar between the bioresorbable scaffold and metallic stent groups (16 patients [5%] vs five patients [3%], p=0.35). Three patients in the bioresorbable scaffold group had definite or probable scaffold thromboses (one definite acute, one definite sub-acute, and one probable late), compared with no patients in the metallic stent group. There were 17 (5%) major cardiac adverse events in the bioresorbable scaffold group compared with five (3%) events in the metallic stent group, with the most common adverse events being myocardial infarction (15 cases [4%] vs two cases [1%], respectively) and clinically indicated target-lesion revascularisation (four cases [1%] vs three cases [2%], respectively). INTERPRETATION: The everolimus-eluting bioresorbable scaffold showed similar 1-year composite secondary clinical outcomes to the everolimus-eluting metallic stent. FUNDING: Abbott Vascular.

Bioresorbable vascular scaffold treatment induces the formation of neointimal cap that seals the underlying plaque without compromising the luminal dimensions: a concept based on serial optical coherence tomography data.

AIMS: To evaluate the implications of an Absorb bioresorbable vascular scaffold (Absorb BVS) on the morphology of the superficial plaques. METHODS AND RESULTS: Forty-six patients who underwent Absorb BVS implantation and 20 patients implanted with bare metal stents (BMS) who had serial optical coherence tomographic examination at baseline and follow-up were included in this analysis. The thin-capped fibroatheromas (TCFA) were identified in the device implantation regions and in the adjacent native coronary segments. Within all regions, circumferential locations of TCFA and calcific tissues were identified, and the neointimal thickness was measured at follow-up. At six to 12-month follow-up, only 8% of the TCFA detected at baseline were still present in the Absorb BVS and 27% in the BMS implantation segment (p=0.231). Sixty percent of the TCFA in native segments did not change their phenotype at follow-up. At short-term follow-up, significant reduction in the lumen area of the BMS was noted, which was higher compared to that reported in the Absorb BVS group (-2.11±1.97 mm2 vs. -1.34±0.99 mm2, p=0.026). In Absorb BVS, neointima tissue continued to develop at midterm follow-up (2.17±0.48 mm2 vs. 1.38±0.52 mm2, p<0.0001) and covered the underlying tissues without compromising the luminal dimensions (5.93±1.49 mm2 vs. 6.14±1.49 mm2, p=0.571) as it was accommodated by the expanded scaffold (8.28±1.74 mm2 vs. 7.67±1.28 mm2, p<0.0001). CONCLUSIONS: Neointimal tissue develops following either Absorb BVS or BMS implantation and shields lipid tissues. The neointimal response in the BMS causes a higher reduction of luminal dimensions compared to the Absorb BVS. Thus, Absorb BVS may have a value in the invasive re-capping of high-risk plaques.

Incidence and imaging outcomes of acute scaffold disruption and late structural discontinuity after implantation of the absorb Everolimus-Eluting fully bioresorbable vascular scaffold: optical coherence tomography assessment in the ABSORB cohort B Trial (A Clinical Evaluation of the Bioabsorbable Everolimus Eluting Coronary Stent System in the Treatment of Patients With De Novo Native Coronary Artery Lesions).

OBJECTIVES: This study sought to describe the frequency and clinical impact of acute scaffold disruption and late strut discontinuity of the second-generation Absorb bioresorbable polymeric vascular scaffolds (Absorb BVS, Abbott Vascular, Santa Clara, California) in the ABSORB (A Clinical Evaluation of the Bioabsorbable Everolimus Eluting Coronary Stent System in the Treatment of Patients With De Novo Native Coronary Artery Lesions) cohort B study by optical coherence tomography (OCT) post-procedure and at 6, 12, 24, and 36 months. BACKGROUND: Fully bioresorbable scaffolds are a novel approach to treatment for coronary narrowing that provides transient vessel support with drug delivery capability without the long-term limitations of metallic drug-eluting stents. However, a potential drawback of the bioresorbable scaffold is the potential for disruption of the strut network when overexpanded. Conversely, the structural discontinuity of the polymeric struts at a late stage is a biologically programmed fate of the scaffold during the course of bioresorption. METHODS: The ABSORB cohort B trial is a multicenter single-arm trial assessing the safety and performance of the Absorb BVS in the treatment of 101 patients with de novo native coronary artery lesions. The current analysis included 51 patients with 143 OCT pullbacks who underwent OCT at baseline and follow-up. The presence of acute disruption or late discontinuities was diagnosed by the presence on OCT of stacked, overhung struts or isolated intraluminal struts disconnected from the expected circularity of the device. RESULTS: Of 51 patients with OCT imaging post-procedure, acute scaffold disruption was observed in 2 patients (3.9%), which could be related to overexpansion of the scaffold at the time of implantation. One patient had a target lesion revascularization that was presumably related to the disruption. Of 49 patients without acute disruption, late discontinuities were observed in 21 patients. There were no major adverse cardiac events associated with this finding except for 1 patient who had a non-ischemia-driven target lesion revascularization. CONCLUSIONS: Acute scaffold disruption is a rare iatrogenic phenomenon that has been anecdotally associated with anginal symptoms, whereas late strut discontinuity is observed in approximately 40% of patients and could be viewed as a serendipitous OCT finding of a normal bioresorption process without clinical implications. (ABSORB Clinical Investigation, Cohort B [ABSORB B]; NCT00856856).

Scaffold and edge vascular response following implantation of everolimus-eluting bioresorbable vascular scaffold: a 3-year serial optical coherence tomography study.

OBJECTIVES: This study sought to investigate the in-scaffold vascular response (SVR) and edge vascular response (EVR) after implantation of an everolimus-eluting bioresorbable scaffold (BRS) using serial optical coherence tomography (OCT) imaging. BACKGROUND: Although studies using intravascular ultrasound have evaluated the EVR in metal stents and BRSs, there is a lack of OCT-based SVR and EVR assessment after BRS implantation. METHODS: In the ABSORB Cohort B (ABSORB Clinical Investigation, Cohort B) study, 23 patients (23 lesions) in Cohort B1 and 17 patients (18 lesions) in Cohort B2 underwent truly serial OCT examinations at 3 different time points (Cohort B1: post-procedure, 6 months, and 2 years; B2: post-procedure, 1 year, and 3 years) after implantation of an 18-mm scaffold. A frame-by-frame OCT analysis was performed at the 5-mm proximal, 5-mm distal edge, and 2-mm in-scaffold margins, whereas the middle 14-mm in-scaffold segment was analyzed at 1-mm intervals. RESULTS: The in-scaffold mean luminal area significantly decreased from baseline to 6 months or 1 year (7.22 ± 1.24 mm(2) vs. 6.05 ± 1.38 mm(2) and 7.64 ± 1.19 mm(2) vs. 5.72 ± 0.89 mm(2), respectively; both p < 0.01), but remained unchanged from then onward. In Cohort B1, a significant increase in mean luminal area of the distal edge was observed (5.42 ± 1.81 mm(2) vs. 5.58 ± 1.53 mm(2); p < 0.01), whereas the mean luminal area of the proximal edge remained unchanged at 6 months. In Cohort B2, the mean luminal areas of the proximal and distal edges were significantly smaller than post-procedure measurements at 3 years. The mean luminal area loss at both edges was significantly less than the mean luminal area loss of the in-scaffold segment at both 6-month and 2-year follow-up in Cohort B1 or at 1 year and 3 years in Cohort B2. CONCLUSIONS: This OCT-based serial EVR and SVR evaluation of the Absorb Bioresorbable Vascular Scaffold (Abbott Vascular, Santa Clara, California) showed less luminal loss at the edges than luminal loss within the scaffold. The luminal reduction of both edges is not a nosologic entity, but an EVR in continuity with the SVR, extending from the in-scaffold margin to both edges. (ABSORB Clinical Investigation, Cohort B [ABSORB B]; NCT00856856).

Temporal evolution of strut light intensity after implantation of bioresorbable polymeric intracoronary scaffolds in the ABSORB cohort B trial-an application of a new quantitative method based on optical coherence tomography.

BACKGROUND: Quantitative light intensity analysis of the strut core by optical coherence tomography (OCT) may enable assessment of changes in the light reflectivity of the bioresorbable polymeric scaffold from polymer to provisional matrix and connective tissues, with full disappearance and integration of the scaffold into the vessel wall. The aim of this report was to describe the methodology and to apply it to serial human OCT images post procedure and at 6, 12, 24 and 36 months in the ABSORB cohort B trial. METHODS AND RESULTS: In serial frequency-domain OCT pullbacks, corresponding struts at different time points were identified by 3-dimensional foldout view. The peak and median values of light intensity were measured in the strut core by dedicated software. A total of 303 corresponding struts were serially analyzed at 3 time points. In the sequential analysis, peak light intensity increased gradually in the first 24 months after implantation and reached a plateau (relative difference with respect to baseline [%Dif]: 61.4% at 12 months, 115.0% at 24 months, 110.7% at 36 months), while the median intensity kept increasing at 36 months (%Dif: 14.3% at 12 months, 75.0% at 24 months, 93.1% at 36 months). CONCLUSIONS: Quantitative light intensity analysis by OCT was capable of detecting subtle changes in the bioresorbable strut appearance over time, and could be used to monitor the bioresorption and integration process of polylactide struts.

1-year clinical outcomes of diabetic patients treated with everolimus-eluting bioresorbable vascular scaffolds: a pooled analysis of the ABSORB and the SPIRIT trials.

OBJECTIVES: The aim of this study was to evaluate 1-year clinical outcomes of diabetic patients treated with the Absorb bioresorbable vascular scaffold (BVS). BACKGROUND: Clinical outcomes of diabetic patients after BVS implantation have been unreported. METHODS: This study included 101 patients in the ABSORB Cohort B trial and the first consecutive 450 patients with 1 year of follow-up in the ABSORB EXTEND trial. A total of 136 diabetic patients were compared with 415 nondiabetic patients. In addition, 882 diabetic patients treated with everolimus-eluting metal stents (EES) in pooled data from the SPIRIT trials (SPIRIT FIRST [Clinical Trial of the Abbott Vascular XIENCE V Everolimus Eluting Coronary Stent System], SPIRIT II [A Clinical Evaluation of the XIENCE V Everolimus Eluting Coronary Stent System], SPIRIT III [Clinical Trial of the XIENCE V Everolimus Eluting Coronary Stent System (EECSS)], SPIRIT IV Clinical Trial [Clinical Evaluation of the XIENCE V Everolimus Eluting Coronary Stent System]) were used for the comparison by applying propensity score matching. The primary endpoint was a device-oriented composite endpoint (DoCE), including cardiac death, target vessel myocardial infarction, and target lesion revascularization at 1-year follow-up. RESULTS: The cumulative incidence of DoCE did not differ between diabetic and nondiabetic patients treated with the BVS (3.7% vs. 5.1%, p = 0.64). Diabetic patients treated with the BVS had a similar incidence of the DoCE compared with diabetic patients treated with EES in the matched study group (3.9% for the BVS vs. 6.4% for EES, p = 0.38). There were no differences in the incidence of definite or probable scaffold/stent thrombosis (0.7% for both diabetic and nondiabetic patients with the BVS; 1.0% for diabetic patients with the BVS vs. 1.7% for diabetic patients with EES in the matched study group). CONCLUSIONS: In the present analyses, diabetic patients treated with the BVS showed similar rates of DoCEs compared with nondiabetic patients treated with the BVS and diabetic patients treated with EES at 1-year follow-up. (ABSORB Clinical Investigation, Cohort B; NCT00856856; ABSORB EXTEND Clinical Investigation; NCT01023789; Clinical Trial of the Abbott Vascular XIENCE V Everolimus Eluting Coronary Stent System [SPIRIT FIRST]; NCT00180453; A Clinical Evaluation of the XIENCE V Everolimus Eluting Coronary Stent System [SPIRIT II]; NCT00180310; Clinical Trial of the XIENCE V Everolimus Eluting Coronary Stent System [EECSS] [SPIRIT III]; NCT00180479; Clinical Evaluation of the XIENCE V Everolimus Eluting Coronary Stent System [SPIRIT IV Clinical Trial]; NCT00307047).

Dynamics of vessel wall changes following the implantation of the absorb everolimus-eluting bioresorbable vascular scaffold: a multi-imaging modality study at 6, 12, 24 and 36 months.

AIMS: To assess observations with multimodality imaging of the Absorb bioresorbable everolimus-eluting vascular scaffold performed in two consecutive cohorts of patients who were serially investigated either at 6 and 24 months or at 12 and 36 months. METHODS AND RESULTS: In the ABSORB multicentre single-arm trial, 45 patients (cohort B1) and 56 patients (cohort B2) underwent serial invasive imaging, specifically quantitative coronary angiography (QCA), intravascular ultrasound (IVUS), radiofrequency backscattering (IVUS-VH) and optical coherence tomography (OCT). Between one and three years, late luminal loss remained unchanged (6 months: 0.19 mm, 1 year: 0.27 mm, 2 years: 0.27 mm, 3 years: 0.29 mm) and the in-segment angiographic restenosis rate for the entire cohort B (n=101) at three years was 6%. On IVUS, mean lumen, scaffold, plaque and vessel area showed enlargement up to two years. Mean lumen and scaffold area remained stable between two and three years whereas significant reduction in plaque behind the struts occurred with a trend toward adaptive restrictive remodelling of EEM. Hyperechogenicity of the vessel wall, a surrogate of the bioresorption process, decreased from 23.1% to 10.4% with a reduction of radiofrequency backscattering for dense calcium and necrotic core. At three years, the count of strut cores detected on OCT increased significantly, probably reflecting the dismantling of the scaffold; 98% of struts were covered. In the entire cohort B (n=101), the three-year major adverse cardiac event rate was 10.0% without any scaffold thrombosis. CONCLUSIONS: The current investigation demonstrated the dynamics of vessel wall changes after implantation of a bioresorbable scaffold, resulting at three years in stable luminal dimensions, a low restenosis rate and a low clinical major adverse cardiac events rate. CLINICAL TRIAL REGISTRATION INFORMATION: http://www.clinicaltrials.gov/ct2/show/NCT00856856.

Procedural and clinical outcomes of the Absorb everolimus-eluting bioresorbable vascular scaffold: one-month results of the Bioresorbable vascular Scaffold Evaluated At Rotterdam Cardiology Hospitals (B-SEARCH).

AIMS: The clinical outcome of patients treated with the everolimus-eluting bioresorbable vascular scaffold (Absorb BVS) in the ABSORB Cohort A and B studies using mandatory intravascular ultrasound (IVUS) imaging showed encouraging results. The ABSORB EXTEND study aimed to include longer lesions, allow overlap and did not oblige IVUS imaging. We assessed the procedural and short-term clinical outcomes in a cohort including these extended criteria. METHODS AND RESULTS: Patients included in three study cohorts (ABSORB Cohort A, Cohort B and EXTEND) at two centres in Rotterdam were systematically followed for major adverse cardiac events (MACE). Clinical data were obtained for 88 patients (mean age 61.2 years, 73% male) with a total of 92 lesions. Lesion length was significantly longer in the ABSORB EXTEND cohort 11.34±4.01 mm (9.20±2.66 mm; p<0.01) and the reference vessel diameter was smaller 2.53±0.34 mm (2.87±0.38 mm; p<0.001) compared to previous cohorts. Predilatation was performed with a balloon diameter of 2.5±0.3 mm and inflated to a maximum pressure of 12.6±3.2 atm. The scaffold was successfully implanted in 90 of the 92 lesions (97.8%) with a maximum pressure of 14.1±2.8 atm. Post-dilatation was performed in 55% of the patients (53% EXTEND vs. 56% Cohort A and B; p=0.7). The acute gain was 1.21±0.37 mm. Absolute recoil was 0.16±0.20 mm with percentage acute recoil of 5.60±6.60%. At one month, none of the patients had a MACE. CONCLUSIONS: This study, which constitutes the largest combined study cohort of patients treated with the Absorb BVS in Rotterdam, shows that treatment of longer lesions and smaller vessels without obligatory IVUS use is safe and efficacious at one month.

The edge vascular response following implantation of the Absorb everolimus-eluting bioresorbable vascular scaffold and the XIENCE V metallic everolimus-eluting stent. First serial follow-up assessment at six months and two years: insights from the first-in-man ABSORB Cohort B and SPIRIT II trials.

AIMS: To assess serially the edge vascular response (EVR) of a bioresorbable vascular scaffold (BVS) compared to a metallic everolimus-eluting stent (EES). METHODS AND RESULTS: Non-serial evaluations of the Absorb BVS at one year have previously demonstrated proximal edge constrictive remodelling and distal edge changes in plaque composition with increase of the percent fibro-fatty (FF) tissue component. The 5 mm proximal and distal segments adjacent to the implanted devices were investigated serially with intravascular ultrasound (IVUS), post procedure, at six months and at two years, from the ABSORB Cohort B1 (n=45) and the SPIRIT II (n=113) trials. Twenty-two proximal and twenty-four distal edge segments were available for analysis in the ABSORB Cohort B1 trial. In the SPIRIT II trial, thirty-three proximal and forty-six distal edge segments were analysed. At the 5-mm proximal edge, the vessels treated with an Absorb BVS from post procedure to two years demonstrated a lumen loss (LL) of 6.68% (-17.33; 2.08) (p=0.027) with a trend toward plaque area increase of 7.55% (-4.68; 27.11) (p=0.06). At the 5-mm distal edge no major changes were evident at either time point. At the 5-mm proximal edge the vessels treated with a XIENCE V EES from post procedure to two years did not show any signs of LL, only plaque area decrease of 6.90% (-17.86; 4.23) (p=0.035). At the distal edge no major changes were evident with regard to either lumen area or vessel remodelling at the same time point. CONCLUSIONS: The IVUS-based serial evaluation of the EVR up to two years following implantation of a bioresorbable everolimus-eluting scaffold shows a statistically significant proximal edge LL; however, this finding did not seem to have any clinical implications in the serial assessment. The upcoming imaging follow-up of the Absorb BVS at three years is anticipated to provide further information regarding the vessel wall behaviour at the edges.

Incidence and short-term clinical outcomes of small side branch occlusion after implantation of an everolimus-eluting bioresorbable vascular scaffold: an interim report of 435 patients in the ABSORB-EXTEND single-arm trial in comparison with an everolimus-eluting metallic stent in the SPIRIT first and II trials.

OBJECTIVES: The aim of this study was to investigate the incidence and clinical sequelae of small side branch occlusion (SBO) after Absorb (Abbott Vascular, Santa Clara, California) bioresorbable vascular scaffold (BVS) implantation. BACKGROUND: The thicker strut of metallic stents potentially contributes to a higher incidence of SBO. METHODS: We performed a post-hoc angiographic assessment of 1,209 side branches in 435 patients enrolled in the ABSORB-EXTEND single-arm trial (ABSORB EXTEND Clinical Investigation: A Continuation in the Clinical Evaluation of the ABSORB Bioresorbable Vascular Scaffold [BVS] System in the Treatment of Subjects With de Novo Native Coronary Artery Lesions), in comparison with 682 side branches in 237 patients treated with the everolimus-eluting metallic stent (EES) in the SPIRIT (A Clinical Evaluation of an Investigational Device. The Abbott XIENCE V Everolimus Eluting Coronary Stent System in the Treatment of Patients With de Novo Native Coronary Artery Lesions) first and II trials. Any visible side branches originating within the device implantation site or the 5-mm proximal and distal margins were included in the angiographic assessment. The SBO was defined as a reduction in Thrombolysis In Myocardial Infarction flow grade 0 or 1. RESULTS: Post-procedural SBO was observed in 73 side branches (6.0%) in BVS group and 28 side branches (4.1%) in EES group (p = 0.09). Patients with post-procedural SBO were significantly associated with an increased incidence of in-hospital myocardial infarction (6.5% in SBO group vs. 0.5% in non-SBO group, p < 0.01). Multivariable analysis revealed that BVS was an independent predictor of post-procedural SBO (odds ratio: 2.09; 95% confidence interval: 1.18 to 3.68). By stratified analysis, BVS demonstrated a higher incidence of post-procedural SBO compared with EES only in small side branches with a reference vessel diameter ≤0.5 mm (10.5% vs. 3.9%, p = 0.03 between the groups, p for interaction = 0.08). CONCLUSIONS: Bioresorbable vascular scaffold was associated with a higher incidence of post-procedural SBO compared with EES. This effect was more pronounced with small side branches with a reference vessel diameter ≤0.5 mm. (ABSORB EXTEND Clinical Investigation: A Continuation in the Clinical Evaluation of the ABSORB Bioresorbable Vascular Scaffold [BVS] System in the Treatment of Subjects With de Novo Native Coronary Artery Lesions: NCT01023789).

Clinical and intravascular imaging outcomes at 1 and 2 years after implantation of absorb everolimus eluting bioresorbable vascular scaffolds in small vessels. Late lumen enlargement: does bioresorption matter with small vessel size? Insight from the ABSORB cohort B trial.

BACKGROUND: The long-term results after second generation everolimus eluting bioresorbable vascular scaffold (Absorb BVS) placement in small vessels are unknown. Therefore, we investigated the impact of vessel size on long-term outcomes, after Absorb BVS implantation. METHODS: In ABSORB Cohort B Trial, out of the total study population (101 patients), 45 patients were assigned to undergo 6-month and 2-year angiographic follow-up (Cohort B1) and 56 patients to have angiographic follow-up at 1-year (Cohort B2). The pre-reference vessel diameter (RVD) was <2.5 mm (small-vessel group) in 41 patients (41 lesions) and ≥2.5 mm (large-vessel group) in 60 patients (61 lesions). Outcomes were compared according to pre-RVD. RESULTS: At 2-year angiographic follow-up no differences in late lumen loss (0.29±0.16 mm vs 0.25±0.22 mm, p=0.4391), and in-segment binary restenosis (5.3% vs 5.3% p=1.0000) were demonstrated between groups. In the small-vessel group, intravascular ultrasound analysis showed a significant increase in vessel area (12.25±3.47 mm(2) vs 13.09±3.38 mm(2) p=0.0015), scaffold area (5.76±0.96 mm(2) vs 6.41±1.30 mm(2) p=0.0008) and lumen area (5.71±0.98 mm(2) vs 6.20±1.27 mm(2) p=0.0155) between 6-months and 2-year follow-up. No differences in plaque composition were reported between groups at either time point. At 2-year clinical follow-up, no differences in ischaemia-driven major adverse cardiac events (7.3% vs 10.2%, p=0.7335), myocardial infarction (4.9% vs 1.7%, p=0.5662) or ischaemia-driven target lesion revascularisation (2.4% vs 8.5%, p=0.3962) were reported between small and large vessels. No deaths or scaffold thrombosis were observed. CONCLUSIONS: Similar clinical and angiographic outcomes at 2-year follow-up were reported in small and large vessel groups. A significant late lumen enlargement and positive vessel remodelling were observed in small vessels.