Morphological and functional evaluation of the bioresorption of the bioresorbable everolimus-eluting vascular scaffold using IVUS, echogenicity and vasomotion testing at two year follow-up: a patient level insight into the ABSORB A clinical trial

The aim of this study was to describe vaso-reactivity (by Acetylcholine and Methergine tests) at 2 year follow-up in parallel with the individual changes in the echogenicity characteristics of the polymer struts of the everolimus eluting bioresorbable vascular scaffold (BVS), from post-treatment to 2 year follow-up, in patients enrolled in the ABSORB Cohort A study. Intravascular ultrasound assessment was performed with a phased array catheter (EagleEye, Volcano Corporation, Cordova, CA, USA) with automated pullback at 0.5 mm per second. The % ratio at 6 months and 2 years [(Scaffold Area post PCI- Lumen Area)/Scaffold Area post PCI] was calculated as a measure of scaffold shrinkage. The % change of hyperechogenicity was defined as: ([post-procedural hyperechogenicity] - [2 year follow up hyperechogenicity])/[post-procedural hyperechogenicity]) × 100. The vasomotion test with intracoronary acetylcholine (10-6M) or intravenous methergine (0.4 mg) was performed at 2 years. Overall nine patients received all these analyses and were enrolled in the present analysis. A 50-96% reduction in hyperechogenicity was observed between baseline and 2 years, which corresponded to a change in vasoreactivity between 2 and 22%. A vasoconstriction of the scaffolded segment was observed in the 5 patients, who underwent the methergine test, with a mean decrease in lumen diameter after met

Two-year clinical, angiographic, and intravascular ultrasound follow-up of the XIENCE V everolimus-eluting stent in the treatment of patients with de novo native coronary artery lesions: the SPIRIT II trial.

BACKGROUND: This article reports the 2-year clinical, angiographic, and intravascular ultrasound outcomes of the everolimus-eluting stent (EES) compared with the paclitaxel-eluting stent (PES) in the randomized SPIRIT II trial. METHODS AND RESULTS: This was a prospective, single-blind clinical trial in which a total of 300 patients with de novo native coronary artery lesions were randomized to either EES or PES in a 3:1 fashion. Clinical follow-up was planned at 2 years in all patients. A subset of 152 patients underwent serial angiographic and intravascular ultrasound analyses at 6 months and 2 years. After 2 years, target lesion failure (cardiac death, myocardial infarction, and ischemia-driven target lesion revascularization) rates were 6.6% and 11% in EES and PES, respectively (P=0.31). At 6 months, a significant reduction in angiographic in-stent late loss and percentage volume obstruction measured by intravascular ultrasound was observed in the EES group. However, at 2-year follow-up, a late increased intimal hyperplasia growth after implantation of an EES was observed. There were no significant differences between EES and PES for in-stent late loss (EES, 0.33+/-0.37 mm versus PES, 0.34+/-0.34 mm; P=0.84) and percentage volume obstruction (EES, 5.18+/-6.22% versus PES, 5.80+/-6.31%; P=0.65) at 2 years. The incidence of stent thrombosis was low and comparable in both groups (EES, 0.9%; PES, 1.4%). CONCLUSIONS: Although the previously reported angiographic and clinical superiority of the EES has vanished over time, this report confirms and extends the previously demonstrated noninferiority in terms of in-stent late loss of the EES when compared with the PES up to 2-year follow-up. There were no significant differences between EES and PES in clinical, angiographic and intravascular ultrasound outcomes at 2 years

A pooled gender based analysis comparing the XIENCE V® everolimus-eluting stent and the TAXUS paclitaxel-eluting stent in male and female patients with coronary artery disease, results of the SPIRIT II and SPIRIT III studies: Two-year analysis

Aims: To assess the safety and efficacy of the XIENCE V everolimus-eluting stent (EES) compared to the TAXUS paclitaxel-eluting stent (PES) in women at two years. Methods and results: In this pooled analysis, a cohort of 395 women and 906 men was studied by using patient level and lesion level clinical data from SPIRIT II and SPIRIT III studies. Women enrolled in these two studies had higher demographic and lesion risk characteristics than their male counterparts. In-stent and insegment late loss (LL) was significantly less in the women in the EES group compared to the women in the PES group (in-stent 0.15±44 mm vs. 0.45±51 mm; P<0.01, in-segment 0.09±46 mm vs. 0.29±40 mm; P<0.01). In women, EES compared to PES resulted in significant reductions in major adverse cardiac events (MACE) (8.5% vs 16.4%; p=0.02) and in target vessel failure (TVF) (11.2% vs 19.5%; p=0.02) at two years. In men, a significant difference was seen in in-stent LL and in-stent % diameter stenosis (DS) favouring EES (in-stent LL 0.14±33 mm vs. 0.28±47 mm; P<0.01, in-stent %DS 9.28±3.86 vs. 13.64±8.31; P<0.01). MACE rates at two years were lower in males treated with EES compared to PES (6.7% vs. 10.9%; p=0.03). The interaction between gender and stent type was not found to be significant for MACE at two years. Conclusions: In this pooled analysis of two randomised trials, at two years, EES compared to PES resulted in reduced angiographic LL, fewer MACE and TVF events in women and reduced angiographic LL and %DS and fewer MACE events in men

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 mm2 [P<0.001]), whereas between 6 and 60 months the LFA remained stable (+0.31±1.00 mm2 [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 mm2 [P=0.017]), whereas the lumen area remained stable (−0.26±1.22 mm2 [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

Vascular compliance changes of the coronary vessel wall after bioresorbable vascular scaffold implantation in the treated and adjacent segments

Background: Implantation of a metallic prosthesis creates local stiffness with a subsequent mismatch in the compliance of the vessel wall, disturbances in flow and heterogeneous distribution of wall shear stress. Polymeric bioresorbable ABSORB scaffolds have less stiffness than metallic platform stents. We sought to analyze the mismatch in vascular compliance after ABSORB implantation and its long-term resolution with bioresorption. Methods and Results: A total of 83 patients from the ABSORB trials underwent palpography investigations (30 and 53 patients from ABSORB Cohorts A and B, respectively) to measure the compliance of the scaffolded and adjacent segments at various time points (from pre-implantation up to 24 months). The mean of the maximum strain values was calculated per segment by utilizing the Rotterdam Classification (ROC) score and expressed as ROC/ mm. Scaffold implantation lead to a significant decrease in vascular compliance (median [IQR]) at the scaffolded segment (from 0.37 [0.24-0.45] to 0.14 [0.09-0.23], P<0.001) with mismatch in compliance in a paired analysis between the scaffolded and adjacent segments (proximal: 0.23 [0.12-0.34], scaffold: 0.12 [0.07-0.19], distal: 0.15 [0.05-0.26], P=0.042). This reported compliance mismatch disappears at short- and mid-term follow-up. Conclusions: The ABSORB scaffold decreases vascular compliance at the site of scaffold implantation. A compliance mismatch is evident immediately post-implantation and in contrast to metallic stents disappears in the mid-term, likely leading to a normalization of the rheological behavior of the scaffolded segment

Angiographic maximal luminal diameter and appropriate deployment of the everolimus-eluting bioresorbable vascular scaffold as assessed by optical coherence tomography: An ABSORB cohort B trial sub-study

Aims: Bioresorbable vascular scaffolds (BVS) present different mechanical properties as compared to metallic platform stents. Therefore, the st

Prediction of atherosclerotic disease progression using LDL transportmodelling: 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 wer

Evaluation of the second generation of a bioresorbable everolimus drug-eluting vascular scaffold for treatment of de novo coronary artery stenosis: Six-month clinical and imaging outcomes

Background-: The first generation of the bioresorbable everolimus drug-eluting vascular scaffold showed signs of shrinkage at 6 months, which largely contributed to late luminal loss. Nevertheless, late luminal loss was less than that observed with bare metal stents. To maintain the mechanical integrity of the device up to 6 months, the scaffold design and manufacturing process of its polymer were modified. Methods and results-: Quantitative coronary angiography, intravascular ultrasound with analysis of radiofrequency backscattering, and as an optional assessment, optical coherence tomography (OCT) were performed at baseline and at a 6-month follow-up. Forty-five patients successfully received a single bioresorbable everolimus drug-eluting vascular scaffold. One patient had postprocedural release of myocardial enzyme without Q-wave occurrence; 1 patient with OCT-diagnosed disruption of the scaffold caused by excessive postdilatation was treated 1 month later with a metallic drug-eluting stent. At follow-up, 3 patients declined recatheterization, 42 patients had quantitative coronary angiography, 37 had quantitative intravascular ultrasound, and 25 had OCT. Quantitative coronary angiography disclosed 1 edge restenosis (1 of 42; in-segment binary restenosis, 2.4%). At variance with the ultrasonic changes seen with the first generation of bioresorbable everolimus drug-eluting vascular scaffold at 6 months, the backscattering of the polymeric struts did not decrease over time, the scaffold area was reduced by only 2.0% with intravascular ultrasound, and no change was noted with OCT. On an intention-to-treat basis, the late lumen loss amounted to 0.19±0.18 mm with a limited relative decrease in minimal luminal area of

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±0.46mm 2, p=0.2), whilst a significant reduction was seen with Revision 1.0 (-0.57±1.3 mm 2, p=0.02). A significant correlation has been found between the change in the DC+NC area and the change in external e

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 r