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).

Occurrence and predictors of acute stent recoil-A comparison between the xience prime cobalt chromium stent and the promus premier platinum chromium stent.

OBJECTIVES: To compare the occurrence of acute stent recoil in two different stent types (platinum chromium and cobalt chromium) and identify the potential predictors of significant acute stent recoil. BACKGROUND: Acute stent recoil is frequently observed after percutaneous coronary intervention and has been associated with in-stent restenosis and in-stent thrombosis. Different stent designs may result in varying degrees of stent recoil. METHODS: From a registry of "all-comers" treated with either the Xience Prime Cobalt Chromium or Promus Premier Platinum Chromium stent, a random sample of 100 patients was drawn. Acute stent recoil was defined as the minimal luminal diameter (MLD) of the last inflated balloon minus the MLD after, divided by the MLD of the last inflated balloon. Significant acute stent recoil was defined as recoil ≥10%. RESULTS: A total of 123 lesions (61 Xience Prime vs 62 Promus Premier) in 100 patients were analyzed. Acute stent recoil of 8.6 ± 4.9% was observed in the Xience Prime group versus 8.7 ± 4.2% in the Promus Premier group, P = 0.970. In a multivariate model for significant acute stent recoil, a stent/vessel ratio ≥1 (hazard ratio 4.64 [1.94-11.12], P = 0.001), a balloon/stent ratio >1 (hazard ratio 3.83 [1.12-13.14], P = 0.032) and direct stenting (hazard ratio 0.42 [0.18-0.96], P = 0.039) were identified as predictors. CONCLUSIONS: No significant differences were observed in the extent of acute stent recoil between the Xience Prime and the Promus Premier stent. A larger stent/vessel ratio, a larger balloon/stent ratio, and direct stenting were associated with significant acute stent recoil ≥10%. © 2017 Wiley Periodicals, Inc.

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.

Postoperative analysis of the mechanical interaction between stent and host tissue in patients after transcatheter aortic valve implantation.

The analysis is based on a finite element procedure to extract the contact forces between an implanted Nitinol stent and the surrounding host tissue using postoperative CT images. The methodology was applied for patients (N=46) which have undergone a TAVI procedure with the Medtronic CoreValve Revalving System (MCRS) to obtain corresponding deformation and force maps. The postoperative CT data were recorded for each patient in both systolic and diastolic phase of the heart cycle. Scalar parameters were defined, which map deformed geometry and contact force field to mechanically relevant quantities: radial dilatation, radial shape distortion, non-convex points, mean force, a force deviation measure and a pressure equivalent. The latter demonstrates that in the area of the aortic root, the added circumferential loading is of the same order as the baseline average blood pressure, thus leading to a doubling of the local mechanical load. Generally the force distribution along the stent is non-homogeneous. A comparison of systolic and diastolic data revealed slightly higher contact forces during the diastole, indicating that the stent has to carry more load in this phase. The geometrical and mechanical parameters were compared for two types of clinical complication: para-valvular leakage (PVL) and permanent pacemaker requirement (PPM). It was found that an increase in mean force can be associated with both complications; significantly for PVL and as a trend for PPM.

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.

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.

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.