Serration Angioplasty Is Associated With Less Recoil in Infrapopliteal Arteries Compared With Plain Balloon Angioplasty

PURPOSE

Recoil following balloon angioplasty of tibial arteries is a known mechanism of lumen loss and widely considered to be a contributing factor in early failure or later restenosis. The Serranator balloon has been designed to provide a controlled lumen gain while minimizing vessel injury. The objective of this study was to assess the ability to define and measure postangioplasty recoil in infrapopliteal arteries and to compare recoil after serration angioplasty and plain balloon angioplasty (POBA).

METHODS

This multi-center, sequential comparative study included patients with de novo or restenotic lesions of infrapopliteal arteries up to 22 cm in length. Patients were enrolled sequentially and underwent alternating POBA or serration angioplasty with Serranator. The study captured angiographic imaging at pre, immediately post, and 15-minute after angioplasty. Vessel recoil, final diameter stenosis, and dissection were compared using core laboratory analysis.

RESULTS

This study enrolled 36 patients who underwent treatment of 39 infrapopliteal lesions. There was no significant difference between Serranator (n=20) and POBA (n=19) with respect to baseline demographics and lesion characteristics. Arterial recoil (>10%) occurred in 25% of Serranator-treated lesions versus 64% in POBA-treated lesions (p=0.02. Clinically relevant recoil (>30%) was present after serration angioplasty in 10% of patients and after POBA in 53% (p=0.01). There was no significant difference in technical success (100% for both), dissection rate between Serranator (5%) and POBA (5.2%).

CONCLUSIONS

Arterial recoil occurs after infrapopliteal angioplasty. Serration angioplasty produces substantially less arterial recoil compared with POBA. Additional studies are needed to assess whether reduced arterial recoil translates into superior long-term clinical outcomes.

CLINICAL IMPACT

Prior studies have demonstrated over 90% recoil in patients after balloon angioplasty (POBA) of the infrapopliteal vessels, which significantly impacts the durability and impact of endovascular interventions in this clinical space. This study compared recoil after infrapopliteal angioplasty with serration angioplasty and POBA. Serration angioplasty produces substantially less arterial recoil compared with POBA. Additional studies are needed to assess whether reduced arterial recoil translates into superior long-term clinical outcomes.

Preliminary testing and evaluation of the renata minima stent, an infant stent capable of achieving adult dimensions

Objectives

This study sought to obtain in vivo data on a new stent and delivery system specifically designed for implantation in infants with the ability to be enlarged to adult dimensions.

Background

There are no endovascular stents designed for or approved for use in infants, nor is there a stent capable of being implanted at infant vessel diameters and achieving adult size while maintaining structural integrity. The Minima stent was designed to address these needs.

Methods

This study was performed in 6 piglets who underwent implantation of 22 Minima stents into the following locations: aorta (n = 11), branch pulmonary arteries (n = 6), and central veins (n = 5).

Results

Successful deployment occurred in 21/22 attempts. Two instances of post‐deployment migration occurred. Stents were re‐expanded at 1, 2, 3 and 5 months after implant. All stents regardless of location could be re‐dilated to the intended diameter to keep pace with somatic growth (implant diameter 6.9 +/− 1.2 mm; final diameter 16.1 mm +/− 1.4 mm). Histopathology at 1 and 5 months demonstrated widely patent vessel lumens with stent apposition to vessel wall, early mild inflammatory response surrounding stent struts, typical vascular damage and healing response to acute dilation and a progressive smooth neointimal growth covering stent struts over time.

Conclusions

In this in vivo study of the Minima stent, there was high implant success, predictable re‐dilatability to adult diameters and favorable histopathology. Further study is warranted.

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.

Comparison of Neointimal Response between Durable-Polymer Everolimus-Eluting Stent and Bioabsorbable-Polymer Everolimus-Eluting Stent for Severely Calcified Lesions Requiring Rotational Atherectomy

Clinical outcomes after percutaneous coronary intervention (PCI) for severely calcified lesions remain poor. The purpose of this study was to investigate the neointimal response after everolimus-eluting stents (EES) for severely calcified lesions treated with rotational atherectomy (RA) using optical coherence tomography (OCT).We retrospectively analyzed 34 lesions in which PCI was performed with EES deployment following RA and OCT was performed immediately after PCI and at follow-up (nine months). The EES was either durable-polymer (DP) EES (22 lesions) or bioabsorbable polymer (BP) -EES (12 lesions). Strut coverage and malapposition were evaluated at 1-mm intervals of cross-section (CS) by serial OCT analysis. Malapposed strut was defined as having the distance from luminal border > 100 μm.A total of 11,823 struts immediately after PCI and 11,720 struts at follow-up were analyzed. Immediately after PCI, the strut-level analysis showed no significant differences in the percentage of malapposed struts between the DP-EES group and the BP-EES group. At follow-up, the BP-EES group showed a more prevalent covered strut compared with the DP-EES group (strut-level analysis: 95% versus 97%, P = 0.045; CS-level analysis: 97% versus 100%, P < 0.01; lesion-level analysis: 27% versus 83%, P < 0.01, respectively).In severely calcified lesions requiring RA, the BP-EES group achieved better neointimal coverage than the DP-EES group at nine months. Additional prospective studies are needed.

Serial invasive imaging follow-up of the first clinical experience with the Magmaris magnesium bioresorbable scaffold

Objectives

To assess the performance of the commercially available Magmaris sirolimus‐eluting bioresorbable scaffold (BRS) with invasive imaging at different time points.

Background

Coronary BRS with a magnesium backbone have been recently studied as an alternative to polymeric scaffolds, providing enhanced vessel support and a faster resorption rate. We aimed to assess the performance of the commercially available Magmaris sirolimus‐eluting BRS at different time points.

Methods

A prospective, single‐center, nonrandomized study was performed at the Thoraxcenter, Erasmus Medical Center, Rotterdam, The Netherlands. Six patients with stable de novo coronary artery lesions underwent single‐vessel revascularization with the Magmaris sirolimus‐eluting BRS. Invasive follow‐up including intravascular imaging using optical coherence tomography (OCT) was performed at different time points.

Results

At a median of 8 months (range 4–12 months) target lesion failure occurred in one patient. Angiography revealed a late lumen loss of 0.59 ± 0.39 mm, a percentage diameter stenosis of 39.65 ± 15.81%, and a binary restenosis rate of 33.3%. OCT showed a significant reduction in both minimal lumen area (MLA) and scaffold area at the site of the MLA by 43.44 ± 28.62 and 38.20 ± 25.74%, respectively. A fast and heterogeneous scaffold degradation process was found with a significant reduction of patent struts at 4–5 months.

Conclusions

Our findings show that the latest iteration of magnesium BRS suffers from premature dismantling, resulting in a higher than expected decrease in MLA.

3D-Printed Sugar-Based Stents Facilitating Vascular Anastomosis

Microvascular anastomosis is a common part of many reconstructive and transplant surgical procedures. While venous anastomosis can be achieved using microvascular anastomotic coupling devices, surgical suturing is the main method for arterial anastomosis. Suture-based microanastomosis is time-consuming and challenging. Here, dissolvable sugar-based stents are fabricated as an assistive tool for facilitating surgical anastomosis. The nonbrittle sugar-based stent holds the vessels together during the procedure and are dissolved upon the restoration of the blood flow. The incorporation of sodium citrate minimizes the chance of thrombosis. The dissolution rate and the mechanical properties of the sugar-based stent can be tailored between 4 and 8 min. To enable the fabrication of stents with desirable geometries and dimensions, 3D printing is utilized to fabricate the stents. The effectiveness of the printed sugar-based stent is assessed ex vivo. The fabrication procedure is fast and can be performed in the operating room.