Stent expansion in calcified coronary chronic total occlusions: The impact of different stent platforms.

OBJECTIVES: To evaluate the stent expansion of the durable-polymer Zotarolimus-eluting stent (dp-ZES), the durable-polymer Everolimus-eluting stent (dp-EES), and the bioabsorbable-polymer Sirolimus-eluting stent (bp-SES) in calcified coronary chronic total occlusions (CTO). BACKGROUND: The newer generation stents with ultrathin struts might raise concerns regarding reduced radial strength and higher stent recoil (SR) when implanted in calcified CTOs. METHODS: Between January 2017 and June 2021 consecutive patients with CTO undergoing percutaneous coronary intervention with dp-ZES, dp-EES, or bp-SES were evaluated. The analysis was performed in calcific and in noncalcific CTOs. Quantitative coronary angiography analysis was used to assess diameter stenosis (DS), absolute and relative SR, absolute and relative focal SR, absolute and relative balloon deficit (BD), and absolute and relative focal BD. The primary endpoint was DS. RESULTS: A total of 213 CTOs were evaluated, 115 calcific CTOs (dp-ZES:25, dp-EES:29, bp-SES:61) and 98 non-calcific CTOs (dp-ZES:41, dp-EES:11, bp-SES:46). In calcific CTOs, residual DS was lower in dp-ZES than in dp-EES and bp-SES (-1.00% [-6.50-6.50] vs. 13.00% [7.0-19.00] vs. 15.00% [5.00-20.00]; p < 0.001). Dp-ZES was also an independent predictor of residual DS ≤ 10% (OR 11.34, 95% CI 2.6-49.43, p = 0.001). Absolute and relative focal SR and absolute and relative SR were similar between dp-ZES, dp-EES, and bp-SES (p = 0.913, p = 0.890, p = 0.518, p = 0.426, respectively). In noncalcified CTOs, the residual DS was similar in the three groups (p = 0.340). High relative focal SR was less frequent in dp-ZES than in dp-EES and in bp-SES (19.5% vs. 54.5% vs. 37.0%; p < 0.048). CONCLUSIONS: The three stent platforms demonstrated an overall low residual DS when implanted in CTOs. However, dp-ZES was associated with the lowest residual DS and identified as independent predictor of residual DS ≤ 10% in patients with calcific CTOs. Dp-ZES was associated with a lower incidence of high relative focal stent recoil, in noncalcific CTOs. Balloon deficit might be considerate as a surrogate for stent expansion in calcified CTOs.

Elastic stent recoil in coronary total occlusions: Comparison of durable-polymer zotarolimus eluting stent and ultrathin strut bioabsorbable-polymer sirolimus eluting stent.

OBJECTIVES: To compare stent recoil (SR) of the thin-strut durable-polymer Zotarolimus-eluting stent (dp-ZES) and the ultrathin-strut bioabsorbable-polymer Sirolimus-eluting stent (bp-SES) in chronic total occlusions (CTOs) and to investigate the predictors of high SR in CTOs. BACKGROUND: Newer ultrathin drug eluting stent might be associated with lower radial force and higher elastic recoil due to the thinner strut design, possibly impacting on the rate of in-stent restenosis and thrombosis. METHODS: Between January 2017 and November 2019, consecutive patients with CTOs undergoing percutaneous coronary intervention were evaluated. Only patients treated with dp-ZES or bp-SES were included and stratified accordingly. Quantitative coronary angiography analysis was used to assess absolute SR, relative SR, absolute focal SR, relative focal SR, high absolute, and high relative focal SR. RESULTS: A total of 128 lesions (67 treated with dp-ZES and 61 with bp-SES) in 123 patients were analyzed. Between bp-SES and dp-ZES no differences were found in absolute SR (p = .188), relative SR (p = .138), absolute focal SR (p = .069), and relative focal SR (p = .064). High absolute and high relative focal SR occurred more frequently in bp-SES than in dp-ZES (p = .004 and p = .015). Bp-SES was a predictor of high absolute focal SR (Odds ratio [OR] 3.29, 95% confidence interval [CI] 1.50-7.22, p = .003]. High-pressure postdilation and bp-SES were predictors of high relative focal SR (OR 2.22, 95% CI 1.01-4.86, p = .047; OR 2.74, 95% CI 1.24-6.02, p = .012, respectively). CONCLUSIONS: Both stents showed an overall low SR. However, ultra-thin strut bp-SES was a predictor of high absolute and high relative focal SR.

Percutaneous complete revascularization strategies using sirolimus-eluting biodegradable polymer-coated stents in patients presenting with acute coronary syndrome and multivessel disease: Rationale and design of the BIOVASC trial.

BACKGROUND: Complete revascularization in patients with an acute coronary syndrome and multivessel disease is superior compared to culprit-only treatment. However, it is unknown whether direct complete or staged complete revascularization should be pursued. METHODS: The BIOVASC study is an investigator-initiated, prospective, multicenter, randomized, 2-arm, international, open-label, noninferiority trial. We will randomize 1,525 patients 1:1 to immediate complete revascularization (experimental arm) or culprit-only plus staged complete revascularization (control arm). Patients will be enrolled in approximately 30 sites in Belgium, Italy, the Netherlands, and Spain. The primary end point is a composite of all-cause mortality, nonfatal myocardial infarction, any unplanned ischemia-driven revascularization (excluding staged procedures in the control arm at the predetermined time), and cerebrovascular events (MACCE) at 1 year post index procedure. CONCLUSIONS: The BIOVASC study aims to further refine the treatment algorithm for acute coronary syndrome patients with multivessel disease in terms of optimal timing for complete revascularization (Clinicaltrials.gov NCT03621501).

Spatial distribution and temporal evolution of scattering centers by optical coherence tomography in the poly(L-lactide) backbone of a bioresorbable vascular scaffold.

BACKGROUND: Scattering centers (SC) are often observed with optical coherence tomography (OCT) in some struts of bioresorbable vascular scaffolds (BVS). These SC might be caused by crazes in the polymer during crimp-deployment (more frequent at inflection points) or by other processes, such as physiological loading or hydrolysis (eventually increasing with time). The spatial distribution and temporal evolution of SC in BVS might help to understand their meaning. METHODS AND RESULTS: Three patients were randomly selected from 12 imaged with Fourier-domain OCT at both baseline and 6 months in the ABSORB cohort B study (NCT00856856). Frame-by-frame analysis of the SC distribution was performed using spread-out vessel charts, and the results from baseline and 6 months were compared. A total of 4,328 struts were analyzed. At baseline and follow-up all SC appeared at inflection points. No significant difference was observed between baseline and 6 months in the number of SC struts (14.9 vs. 14.5%, P=0.754) or in the distribution of SC. The proportion and distribution of SC did not vary substantially among the patients analyzed. CONCLUSIONS: The SC observed in OCT imaging of the BVS are located exclusively at inflection points and do not increase with time. These findings strongly suggest that SC are caused by crazes in the polymer during crimp-deployment, ruling out any major role of hydrolysis or other time-dependent processes.

A comparative assessment by optical coherence tomography of the performance of the first and second generation of the everolimus-eluting bioresorbable vascular scaffolds.

AIMS: The first generation of the everolimus-eluting bioresorbable vascular scaffold (BVS 1.0) showed an angiographic late loss higher than the metallic everolimus-eluting stent Xience V due to scaffold shrinkage. The new generation (BVS 1.1) presents a different design and manufacturing process than the BVS 1.0. This study sought to evaluate the differences in late shrinkage, neointimal response, and bioresorption process between these two scaffold generations using optical coherence tomography (OCT). METHODS AND RESULTS: A total of 12 lesions treated with the BVS 1.0 and 12 selected lesions treated with the revised BVS 1.1 were imaged at baseline and 6-month follow-up with OCT. Late shrinkage and neointimal area (NIA) were derived from OCT area measurements. Neointimal thickness was measured in each strut. Strut appearance has been classified as previously described. Baseline clinical, angiographic, and OCT characteristics were mainly similar in the two groups. At 6 months, absolute and relative shrinkages were significantly larger for the BVS 1.0 than for the BVS 1.1 (0.98 vs. 0.07 mm² and 13.0 vs. 1.0%, respectively; P = 0.01). Neointimal area was significantly higher in the BVS 1.0 than in the BVS 1.1 (in-scaffold area obstruction of 23.6 vs. 12.3%; P < 0.01). Neointimal thickness was also larger in the BVS 1.0 than in the BVS 1.1 (166.0 vs. 76.4 µm; P < 0.01). Consequently, OCT, intravascular ultrasound, and angiographic luminal losses were higher with the BVS 1.0 than with the BVS 1.1. At 6 months, strut appearance was preserved in only 2.9% of the BVS 1.0 struts, but remained unchanged with the BVS 1.1 indicating different state of strut microstucture and/or their reflectivity. CONCLUSION: The BVS 1.1 has less late shrinkage and less neointimal growth at 6-month follow-up compared with the BVS 1.0. A difference in polymer degradation leading to changes in microstructure and reflectivity is the most plausible explanation for this finding.

Procedural Performance of Ultrathin, Biodegradable Polymer-Coated Stents Versus Durable Polymer-Coated Stents Based on Intracoronary Imaging.

OBJECTIVE: Thinner stent struts might lead to a higher risk of recoil and subsequently a smaller minimal stent area (MSA), which is known to be the strongest predictor of stent failure. We compared procedural performance between an ultrathin-strut biodegradable-polymer sirolimus-eluting stent (BP-SES) and a durable-polymer zotarolimus-eluting stent (DP-ZES) using intracoronary imaging. METHODS: A consecutive cohort of patients underwent percutaneous coronary intervention (PCI) with either BP-SES or DP-ZES in a pseudorandomized fashion between July 2018 and October 2019. In the present subanalysis, we included cases in which post-PCI imaging with intravascular ultrasound (IVUS) or optical coherence tomography (OCT) was performed. The primary endpoint of the study was MSA. Secondary endpoints included percentage stent expansion and presence of residual edge disease, malapposition, tissue protrusion, submedial edge dissections, or edge hematoma. RESULTS: A total of 141 treated lesions (78 BP-SES and 63 DP-ZES) in 127 patients were analyzed. Median age was 69.3 years (interquartile range [IQR], 57.3-75.6) and 74.0% of patients were male. All baseline and procedural characteristics were comparable between both groups. Median MSA was 5.80 mm² (IQR, 4.40-7.24) for BP-SES and 6.35 mm² (IQR, 4.76-8.31) for DP-ZES (P=.15). No significant differences in stent expansion, residual edge disease and presence of malapposition, tissue protrusion, submedial edge dissections, or edge hematomas were found. Stent diameter and stent length were found to be independent predictors of MSA. CONCLUSIONS: No significant differences in MSA were found between lesions treated with BP-SES vs DP-ZES. BP-SES and DP-ZES were comparable in terms of procedural performance.

Conformability in everolimus-eluting bioresorbable scaffolds compared with metal platform coronary stents in long lesions.

The aim of this study was to determine if there are significant differences in curvature of the treated vessel after the deployment of a polymeric BRS or MPS in long lesions. The impact of long polymeric bioresorbable scaffolds (BRS) compared with metallic platform stents (MPS) on vessel curvature is unknown. This retrospective study compares 32 patients who received a single everolimus-eluting BRS with 32 patients treated with a single MPS of 28 mm. Quantitative coronary angiography (QCA) was used to evaluate curvature of the treatment and peri-treatment region before and after percutaneous coronary intervention (PCI). Baseline demographic and angiographic characteristics were similar between the BRS and MPS groups. Pretreatment lesion length was 22.19 versus 20.38 mm in the BRS and MPS groups respectively (p = 0.803). After treatment, there was a decrease in median diastolic curvature in the MPS group (from 0.257 to 0.199 cm-1, p = 0.001). A similar trend was observed in the BRS group but did not reach statistical significance (median diastolic curvature from 0.305 to 0.283 cm-1, p = 0.056). Median Percentage relative change in diastolic curvature was lower in the BRS group compared with the MPS group (BRS vs. MPS: 7.48 vs. 29.4%, p = 0.013). By univariate analysis, use of MPS was an independent predictor of change in diastolic curvature (p = 0.022). In the deployment of long coronary scaffolds/stents (28 mm in length), BRS provides better conformability compared with MPS.

Potentially increased incidence of scaffold thrombosis in patients treated with Absorb BVS who terminated DAPT before 18 months.

AIMS: The aim of this study was to investigate the impact of dual antiplatelet therapy (DAPT) termination on late and very late scaffold thrombosis (ScT) in patients treated with the Absorb bioresorbable vascular scaffold (BVS). METHODS AND RESULTS: Data from the registries of three centres were pooled (808 patients). To investigate the effect of DAPT termination on ScT after a minimum of six months, we selected a subgroup ("DAPT study cohort" with 685 patients) with known DAPT status >6 months and excluded the use of oral anticoagulants and early ScT. In this cohort, definite/probable ScT incidence for the period on DAPT was compared to ScT incidence after DAPT termination. ScT incidence was 0.83 ScT/100 py with 95% confidence interval (CI): 0.34-1.98. After DAPT termination, the incidence was higher (1.77/100 py; 95% CI: 0.66-4.72), compared to the incidence on DAPT (0.26/100 py, 95% CI: 0.04-1.86; p=0.12) and increased within the month after DAPT termination (6.57/100 py, 95% CI: 2.12-20.38; p=0.01). No very late ScT occurred in patients who continued on DAPT for a minimum of 18 months. CONCLUSIONS: The incidence of late and very late definite/probable ScT was acceptable. The incidence was low while on DAPT but potentially higher when DAPT was terminated before 18 months.

The Promus Premier everolimus-eluting platinum chromium stent with durable polymer evaluated in a real world all-comer population in Rotterdam cardiology hospital (the P-SEARCH registry).

BACKGROUND: A new-generation everolimus eluting platinum-chromium stent (EePCS), offering improved radial strength, radiopacity and conformability compared to everolimus-eluting cobalt-chromium stents (EeCCS), was evaluated with regard to safety and efficacy in an all-comer cohort. METHODS: A total of 1000 consecutive all-comer patients (including acute coronary syndrome, multivessel disease, calcified lesions) treated with an EePCS (Promus Premier™, Boston Scientific, Natick, Massachusetts) from May 2013 to October 2014 were compared to 1000 consecutive patients treated with an EeCCS (Xience Prime™, Abbott Vascular, Santa Clara, California) from April 2012 to May 2013. Patients were clinically followed for 1year. RESULTS: Mean age was 66±12years with diabetes in 20.7%, previous infarction in 22.7%, and ACS as the indication in 71.2% of patients. The mean number of stents per patient was 1.8±1.13. Total stented length was 35±25mm. Lesion classification was B2/C in 73.9% of patients. At 1year the primary endpoint of major adverse cardiac events (all-cause mortality, myocardial infarction [MI], ischemia-driven target vessel revascularization [TVR]) was reached in 11.7% in the EePCS cohort and 10.9% in the EeCCS cohort (adjusted HR 1.01 [0.77-1.33]; p=0.95). No significant differences were noted in the individual clinical endpoints all-cause mortality (6.8% versus 6.4%), MI (2.2% versus 2.3%), and TVR (4.3% versus 3.7%) in the respective EePCS and EeCCS cohorts. Stent thrombosis occurred in 0.8% and 1.0% respectively. CONCLUSIONS: In all-comer patients undergoing percutaneous coronary intervention, the use of EePCS was associated with similar 1-year clinical outcome as compared to EeCCS.

Effectiveness of a novel biodegradable polymer, sirolimus-eluting stent platform in percutaneous coronary intervention.

BACKGROUND: The purpose of this registry is to report the immediate and long-term safety and efficacy of the Biotronik Orsiro stent in an unselected population during everyday practice. METHODS: Between May 2012 and June 2013, 246 consecutive coronary angioplasty procedures were performed using at least one Orsiro drug-eluting stent, in 225 patients and 303 lesions. RESULTS: Diabetes was present in 34.7% of patients. Procedures were non-elective percutaneous coronary intervention (PCI) in 17.1% of cases and acute coronary syndromes were 55.1%. Radial vascular access was used in 78% of cases, multivessel PCI was performed in 19.5% of the procedures. In 81.6% of cases lesions were B2/C type, 20.7% of procedures had bifurcation lesions. Procedural success was 99.6%. No acute thrombosis occurred. Clinical follow-up median period was 24.3 (±8.28) months and FU was available in 93.7% of patients. Death for any cause occurred in 11 patients (5.2%), 6 of them were non cardiac-related. Cardiac-related death rate was 2.4%. Two patients had in-stent restenosis. The overall target lesion failure rate was 3.3%. CONCLUSIONS: This observational data regards our experience with Biotronik Orsiro stent in an unselected population. This initial data, although limited by a mainly clinical follow-up and restricted number of patients, confirms the good clinical performance of this sirolimus-eluting stent with a biodegradable polymer in everyday practice, including complex lesions, according to current larger studies in the literature.

Everolimus-eluting bioresorbable vascular scaffolds implanted in coronary bifurcation lesions: Impact of polymeric wide struts on side-branch impairment.

BACKGROUND: Limited data are available on bioresorbable vascular scaffolds (BVS) performance in bifurcations lesions and on the impact of BVS wider struts on side-branch impairment. METHODS: Patients with at least one coronary bifurcation lesion involving a side-branch ≥2mm in diameter and treated with at least one BVS were examined. Procedural and angiographic data were collected and a dedicated methodology for off-line quantitative coronary angiography (QCA) in bifurcation was applied (eleven-segment model), to assess side-branch impairment occurring any time during the procedure. Two- and three-dimensional QCA were used. Optical coherence tomography (OCT) analysis was performed in a subgroup of patients and long-term clinical outcomes reported. RESULTS: A total of 102 patients with 107 lesions, were evaluated. Device- and procedural-successes were 99.1% and 94.3%, respectively. Side-branch impairment occurring any time during the procedure was reported in 13 bifurcations (12.1%) and at the end of the procedure in 6.5%. Side-branch minimal lumen diameter (Pre: 1.45±0.41mm vs Final: 1.48±0.42mm, p=0.587) %diameter-stenosis (Pre: 26.93±16.89% vs Final: 27.80±15.57%, p=0.904) and minimal lumen area (Pre: 1.97±0.89mm(2) vs Final: 2.17±1.09mm(2), p=0.334), were not significantly affected by BVS implantation. Mean malapposed struts at the bifurcation polygon-of-confluence were 0.63±1.11. CONCLUSIONS: The results of the present investigation suggest feasibility and relative safety of BVS implantation in coronary bifurcations. BVS wide struts have a low impact on side-branch impairment when considering bifurcations with side-branch diameter≥2mm.

Mid- to Long-Term Clinical Outcomes of Patients Treated With the Everolimus-Eluting Bioresorbable Vascular Scaffold: The BVS Expand Registry.

OBJECTIVES: This study sought to report on clinical outcomes beyond 1 year of the BVS Expand registry. BACKGROUND: Multiple studies have proven feasibility and safety of the Absorb bioresorbable vascular scaffold (BVS) (Abbott Vascular, Santa Clara, California). However, data on medium- to long-term outcomes are limited and available only for simpler lesions. METHODS: This is an investigator-initiated, prospective, single-center, single-arm study evaluating performance of the BVS in a lesion subset representative of daily clinical practice, including calcified lesions, total occlusions, long lesions, and small vessels. Inclusion criteria were patients presenting with non-ST-segment elevation myocardial infarction, stable/unstable angina, or silent ischemia caused by a de novo stenotic lesion in a native previously untreated coronary artery. Procedural and medium- to long-term clinical outcomes were assessed. Primary endpoint was major adverse cardiac events, defined as a composite of cardiac death, myocardial infarction, and target lesion revascularization. RESULTS: From September 2012 to January 2015, 249 patients with 335 lesions were enrolled. Mean number of scaffolds per patient was 1.79 ± 1.15. Invasive imaging was used in 39%. In 38.1% there were American College of Cardiology/American Heart Association classification type B2/C lesions. Mean lesion length was 22.16 ± 13.79 mm. Post-procedural acute lumen gain was 1.39 ± 0.59 mm. Median follow-up period was 622 (interquartile range: 376 to 734) days. Using Kaplan-Meier methods, the MACE rate at 18 months was 6.8%. Rates of cardiac mortality, myocardial infarction, and target lesion revascularization at 18 months were 1.8%, 5.2%, and 4.0%, respectively. Definite scaffold thrombosis rate was 1.9%. CONCLUSIONS: In our study, BVS implantation in a complex patient and lesion subset was associated with an acceptable rate of adverse events in the longer term, whereas no cases of early thrombosis were observed.

Impact of biodegradable versus durable polymer drug-eluting stents on clinical outcomes in patients with coronary artery disease: a meta-analysis of 15 randomized trials.

BACKGROUND: Drug eluting stents (DESs) made with biodegradable polymer have been developed in an attempt to improve clinical outcomes. However, the impact of biodegradable polymers on clinical events and stent thrombosis (ST) remains controversial. METHODS: We searched Medline, the Cochrane Library and other internet sources, without language or date restrictions for articles comparing clinical outcomes between biodegradable polymer DES and durable polymer DES. Safety endpoints were ST (definite, definite/probable), mortality, and myocardial infarction (MI). Efficacy endpoints were major adverse cardiac event (MACE) and target lesion revascularization (TLR). RESULTS: We identified 15 randomized controlled trials (n = 17 068) with a weighted mean follow-up of 20.6 months. There was no statistical difference in the incidence of definite/probable ST between durable polymer- and biodegradable polymer- DES; relative risk (RR) 0.83; 95% confidence interval (CI) 0.62-1.11; P = 0.22. Biodegradable polymer DES had similar rates of definite ST (RR 0.94, 95% CI 0.66-1.33, P = 0.72), mortality (RR 0.94, 95% CI 0.82-1.09, P = 0.43), MI (RR 1.08, 95% CI 0.92-1.26. P = 0.35), MACE (RR 0.99, 95% CI 0.91-1.09, P = 0.85), and TLR (RR, 0.94, 95% CI 0.83-1.06, P = 0.30) compared with durable polymer DES. Based on the stratified analysis of the included trials, the treatment effect on definite ST was different at different follow-up times: ≤ 1 year favoring durable polymer DES and >1 year favoring biodegradable polymer DES. CONCLUSIONS: Biodegradable polymer DES has similar safety and efficacy for treating patients with coronary artery disease compared with durable polymer DES. Further data with longer term follow-up are warranted to confirm the potential benefits of biodegradable polymer DES.

Clinical and angiographic outcomes following first-in-man implantation of a novel thin-strut low-profile fixed-wire stent: the Svelte Coronary Stent Integrated Delivery System first-in-man trial.

AIMS: The Svelte Stent Integrated Delivery System (IDS) is a novel fixed-wire thin-strut cobalt-chromium stent characterised by a very low entry profile. The aim of the present study is to evaluate the safety and the feasibility of the Svelte stent IDS implantation in humans. METHODS AND RESULTS: The present investigation is a prospective, multicentre non-randomised single-arm study. The primary endpoint was freedom from major adverse cardiac events (MACE) at 30 days post-procedure. Invasive follow-up was scheduled at six months post implantation. A total of 47 patients were enrolled and serial OCT imaging was performed in a subgroup of 18 patients. At the index procedure the lesion success rate was 97.9% (46 patients), the mean acute gain was 1.56 ± 0.43 mm with a mean minimum lumen diameter of 2.48 ± 0.43 mm. Post-implantation OCT imaging revealed a minimal mean prolapse area (0.10 ± 0.06 mm²), mean incomplete stent apposition area (0.12 ± 0.13 mm²) and mean intraluminal mass area (0.05 ± 0.03 mm²). Edge dissections were reported in eight cases (mean dissection width 0.17 ± 0.07 mm proximally and 0.25 ± 0.24 mm distally). At 30-day clinical follow-up, one case of myocardial infarction was reported. At six months, the angiographic mean in-stent late loss was 0.95 ± 0.76 mm. By OCT, a high percentage of struts was covered (97.6 ± 15.00 %) with a mean neointimal thickness of 0.31 ± 0.14 mm, all edge dissections were clinically silent and healed. Target lesion revascularisation (TLR) occurred in 11 patients (23.4%) and clinically driven TLR in three of these patients (6.4%). No cases of death or stent thrombosis were reported during the study. CONCLUSIONS: Implantation of the Svelte stent IDS was observed to be safe, feasible and associated with a low acute vascular injury and a high percentage of strut coverage at 6-month follow-up.

Plaque sealing and passivation with a mechanical self-expanding low outward force nitinol vShield device for the treatment of IVUS and OCT-derived thin cap fibroatheromas (TCFAs) in native coronary arteries: report of the pilot study vShield Evaluated at Cardiac hospital in Rotterdam for Investigation and Treatment of TCFA (SECRITT).

AIMS: The aim of the pilot SECRITT trial was to evaluate the safety and feasibility of sealing the high risk IVUS and optical coherence tomography-derived thin cap fibroatheroma (TCFA), with a dedicated nitinol self-expanding vShield device. METHODS AND RESULTS: After screening with angiography, fractional flow reserve (FFR), intravascular ultrasound virtual histology (IVUS-VH) and optical coherence tomography (OCT), 23 patients met enrolment criteria (presence of non-obstructive VH-derived TCFA lesion with thin cap on OCT) and were randomised to vShield (n=13) versus medical therapy (n=10). In the shielded group, baseline percent diameter stenosis was 33.2±13.5%, FFR was 0.93±0.06. At six-month follow-up in shielded patients percent diameter stenosis further decreased to 18.7±16.9% and FFR remained the same 0.93±0.05. Average late loss was 0.24±0.13 mm. Average baseline fibrous cap thickness was 48±12 µm. After shield placement at six-month follow-up neo-cap formation was observed with average cap thickness of 201±168 µm. There were no dissections after shield placement and no plaque ruptures. In addition, mean stent area of 8.76±2.16 mm2 increased to 9.45±2.30 mm2, that is by 9% at six-month follow-up. The number of malapposed struts decreased from 10.7% to 7.6% and the number of uncovered struts at six months was 8.1%. There were no device-related major adverse cardiovascular events (MACE) events at six-month follow-up. CONCLUSIONS: High risk plaque passivation and sealing with a vShield self-expanding nitinol device appears feasible and safe. A long-term larger randomised study with streamlined screening criteria is needed to evaluate the efficacy of this approach over medical therapy.

Comparison between the first and second generation bioresorbable vascular scaffolds: a six month virtual histology study.

AIMS: To compare the intravascular ultrasound virtual histology (IVUS-VH) appearance of the polymeric struts of the first (Revision 1.0) and the second (Revision 1.1) generation bioresorbable vascular scaffold (BVS). METHODS AND RESULTS: IVUS-VH misrepresents polymeric struts as dense calcium (DC) and necrotic core (NC) so that their presence and disappearance could be used as potential artifactual surrogate of bioresorption. DC and NC were assessed in both revisions of the BVS by analysing IVUS-VH from all patients in the ABSORB cohort A (Revision 1.0) and cohort B (Revision 1.1) study who had an IVUS-VH post-treatment and at 6-month follow-up. Post-treatment and 6-month follow-up IVUS-VH results, available in 60 patients (BVS 1.0 n=28; BVS 1.1 n=32), indicated an insignificant rise in DC+NC area compared to baseline with Revision 1.1 (0.10 ± 0.46 mm2, p=0.2), whilst a significant reduction was seen with Revision 1.0 (-0.57 ± 1.3 mm2, p=0.02). A significant correlation has been found between the change in the DC+NC area and the change in external elastic membrane area (y=0.68x-0.1; r=0.58, p=0.03). CONCLUSIONS: Based on 6-months IVUS-VH analysis, the BVS 1.1 appears to have a different backscattering signal compared to the BVS 1.0, which may reflect differences in the speed of chemical and structural alteration.

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).