Comparison of overexpansion capabilities and thrombogenicity at the side branch ostia after implantation of four different drug eluting stents

Long-Term Safety and Performance of BioMime™ Morph Sirolimus-Eluting Coronary Stent System for Very Long Coronary Lesions

Background

The use of multiple overlapping stents for long lesions in tapered coronary arteries has been associated with poor outcomes. This study was conducted to evaluate the 3-year safety and performance of the BioMime™ Morph sirolimus-eluting stent (SES) in very long (length 30 to ≤ 56 mm) coronary lesions in native coronary arteries with a reference vessel diameter of 2.25 to 3.50 mm.

Methods

This was a prospective, single-center, observational, real-world, post-marketing surveillance study. Eligible patients were implanted with BioMime™ Morph SES. Patients were followed up at 6, 12, 24, and 36 months.

Results

A total of 88 patients were enrolled in the study. The mean age was 58.72 ± 10.10 years and 82.95% were male. Most patients had angina (81.82%) and ischemic heart disease (78.41%), and there was a high prevalence of comorbidities like diabetes mellitus (59.09%), and hypertension (54.55%). A total of 92 long coronary de novo lesions were treated with BioMime™ Morph SES with an average stent length of 45.54 ± 10.20 mm. Device and procedural success rates were 100%. One patient died at 30 days and one case of myocardial infarction was recorded. The cumulative rates of major adverse cardiovascular events (MACEs) at 6, 12, 24, and 36 months were 3.41%, 6.82%, 7.95%, and 7.95%, respectively. There were no cases of stent thrombosis (ST), ischemia-driven target vessel revascularization, or ischemia-driven target lesion revascularization until 36 months of follow-up.

Conclusion

BioMime™ Morph SES showed favorable outcomes up to 3 years in treating very long coronary lesions in native coronary arteries, as demonstrated by an acceptable rate of MACEs and absence of ST, based on clinical outcomes up to 3 years.

The Randomized, Multicenter, Open-Label, Controlled POLBOS 3 Trial Comparing Regular Drug-Eluting Stents and the Sirolimus-Eluting BiOSS LIM C Dedicated Coronary Bifurcation Stent: Four-Year Results

This multicenter, randomized study aimed to compare the sirolimus-eluting BiOSS LIM C dedicated coronary bifurcation stent with second-generation -limus drug-eluting stents (rDESs) in the treatment of non-left main (non-LM) coronary bifurcation. The deployment of a single stent in the main vessel-main branch across a side branch was the default strategy in all patients. The primary endpoint was the rate of major cardiovascular events (cardiac death, myocardial infarction, and target lesion revascularization) at 48 months. We enrolled 230 patients, allocating 116 patients to the BiOSS LIM C group and 114 patients to the rDES group. Most procedures were elective (BiOSS vs. rDES: 48.3% vs. 59.6%, p = 0.09) and performed in bifurcations within the left anterior descending/diagonal branch (BiOSS vs. rDES: 51.7% vs. 61.4%, p = 0.15). At 48 months, there were no statistically significant differences between the BiOSS and rDES groups in terms of major adverse cardiovascular events (MACE), cardiac death, myocardial infarction (MI), or target lesion revascularization (TLR) as follows: MACEs-18.1% vs. 14.9%, HR 1.36, 95% CI 0.62-2.22, and p = 0.33; cardiac death-4.3% vs. 3.5%, HR 1.23, 95% CI 0.33-4.56, and p = 0.75; MI-2.6% vs. 3.5%, HR 0.73, 95% CI 0.17-3.23, and p = 0.68; and TLR-11.2% vs. 7.9%, HR 1.66, 95% CI 0.75-3.71, and p = 0.21. The implantation success rate of the BiOSS LIM C stent was very high, and the cumulative MACE rates were promising. The POLBOS 3 trial sets an important benchmark for treating non-LM coronary bifurcations (ClinicalTrials.gov NCT03548272).

Drug-Eluting Stents: Technical and Clinical Progress

Drug-eluting stents (DES) demonstrated superior efficacy when compared to bare metal stents and plain-old balloon angioplasty and are nowadays used in almost all percutaneous revascularization procedures. The design of the stent platforms is constantly improving to maximize its efficacy and safety. Constant development of DES includes adoption of new materials used for scaffold production, new design types, improved overexpansion abilities, new polymers coating and, finally, improved antiproliferative agents. Especially nowadays, with the immense number of available DES platforms, it is crucial to understand how different aspects of stents impact the effect of their implantation, as subtle differences between various stent platforms could impact the most important issue-clinical outcomes. This review discusses the current status of coronary stents and the impact of stent material, strut design and coating techniques on cardiovascular outcomes.

Polymer Coating Integrity, Thrombogenicity and Computational Fluid Dynamics Analysis of Provisional Stenting Technique in the Left Main Bifurcation Setting: Insights from an In-Vitro Model

Currently, the provisional stenting technique is the gold standard in revascularization of lesions located in the left main (LM) bifurcation. The benefit of the routine kissing balloon technique (KBI) in bifurcation lesions is still debated, particularly following the single stent treatment. We compared the latest-generation drug-eluting stent (DES) with no side branch (SB) dilatation “keep it open” technique (KIO) vs. KBI technique vs. bifurcation dedicated drug-eluting stent (BD-DES) implantation. In vitro testing was performed under a static condition in bifurcation silicone vessel models. All the devices were implanted in accordance with the manufacturers’ recommendations. As a result, computational fluid dynamics (CFD) analysis demonstrated a statistically higher area of high shear rate in the KIO group when compared to KBI. Likewise, the maximal shear rate was higher in number in the KIO group. Floating strut count based on the OCT imaging was significantly higher in KIO than in KBI and BD-DES. Furthermore, according to OTC analysis, the thrombus area was numerically higher in both KIO and KBI than in the BD-DES. Scanning electron microscopy (SEM) analysis shows the highest degree of strut coating damage in the KBI group. This model demonstrated significant differences in CFD analysis at SB ostia with and without KBI optimization in the LM setting. The adoption of KBI was related to a meaningful reduction of flow disturbances in conventional DES and achieved results similar to BD-DES.

Application of moving particle semi-implicit (MPS) method on retro-oil fluid using three-dimensional vitreous cavity models from magnetic resonance imaging

Silicone oil (SO) is a safe and widely used intraocular tamponade agent for treating complicated vitreoretinal diseases, such as retinal detachments (RRDs) with inferior proliferative vitreoretinopathy (PVR). However, as the human vitreous cavity is irregularly shaped, it is difficult to predict the area of the inferior retina covered with SO and the retro-oil fluid currents in each patient. Here, we performed fluid simulation analysis using the moving particle semi-implicit method on the oil cover rates and absolute velocity gradient of retro-oil fluid to the retina using vitreous cavity models derived from magnetic resonance imaging of patients to determine the appropriate amount of SO and postoperative position to achieve a sufficient tamponade effect on the inferior retina. In all seven vitreous cavity models tested, the inferior quadrant of the retina was completely covered by SO in more positions and the absolute velocity gradient of the retro-oil fluid in contact with the retinal wall caused by eye and head movements was lower when the vitreous cavity was filled with 95% SO and 5% retro-oil fluid versus 80% SO and 20% retro-oil fluid. Taken together, these findings have clinical implications for the treatment of complicated RRDs with inferior PVR requiring SO tamponade.

Side-branch expansion capacity of contemporary DES platforms

Background

Percutaneous coronary interventions (PCI) of bifurcation stenoses are both complex and challenging. Stenting strategies share that the stents’ side cells must be carefully explored and appropriately prepared using balloons or stents. So far, stent manufacturers have not provided any information regarding side-branch expansion capacity of their stent platforms.

Aims

Given that drug-eluting stent (DES) information regarding their mechanical capacity of side-branch expansion is not available, we aimed to evaluate contemporary DES (Orsiro, BIOTRONIK AG; Xience Sierra, Abbott Vascular; Resolute Integrity, Medtronic; Promus Premier Select, Boston Scientific; Supraflex Cruz, Sahajan and Medical Technologies) by their side-branch expansion behavior using in vitro bench testing.

Methods

In this in vitro study, we analyzed five commercially available DES (diameter 3.0 mm), measuring their side-branch expansion following inflation of different high-pressure non-compliant (NC) balloons (balloon diameter: 2.00–4.00 mm), thereby revealing the morphological characteristics of their side-branch expansion capacities.

Results

We demonstrated that all tested contemporary DES platforms could withstand large single-cell deformations, up to 4.0 mm. As seen in our side-branch experiments, DES designs consisting of only two connectors between strut rings did not only result in huge cell areas, but also in larger cell diameters following side-branch expansion compared with DES designs using three or more connectors. Furthermore, the stent cell diameter attained was below the balloon diameter at normal pressure.

Conclusions

We recommend that the expansion capacity of side-branches should be considered in stent selection for bifurcation interventions.

6-year results of BiOSS stents in coronary bifurcation treatment

BACKGROUND

The wide variation in bifurcation anatomy has generated an ongoing search for stents explicitly designed for coronary bifurcations, and to date, results have been underachieved.

METHODS

The POLBOS I and POLBOS II were international, multicentre, randomized, open-label, controlled trials. Patients were randomly assigned to BiOSS Expert (in POLBOS I, biodegradable polymer eluting paclitaxel)/BiOSS LIM (in POLBOS II, biodegradable polymer eluting sirolimus) stent implantation or regular drug-eluting stent (rDES) deployment. A provisional T-stenting strategy was the default treatment option. The primary endpoint of this pooled data study was the cumulative rate of major adverse cardiovascular events (MACE) consisting of cardiac death, myocardial infarction (MI) and target lesion revascularization (TLR). Telephone follow-up was performed annually up to 72 months. (ClinicalTrials.gov Identifier: POLBOS I-NCT02192840, POLBOS II-NCT02198300).

RESULTS

The total study population consisted of 445 patients, 222 patients in the BiOSS group and 223 patients in the rDES group. The follow-up rate was 93.7% in the BiOSS group and 91.9% in the rDES group. At 72 months, there was no significant difference between BiOSS and rDES groups regarding MACE (25.7% vs 25.1%, HR 1.06, 95% CI 0.73-1.52), cardiac death (3.1% vs 4.0%, HR 0.94, 95% CI 0.43-2.34), MI (3.6% vs 4.9%, HR 0.76, 95% CI 0.32-2.89), TLR (18.9% vs 16.1%, HR 1.17, 95% CI 0.75-1.83) and stent thrombosis rates (0.9% vs 0.5%, HR 1.21, 95CI 0.75-2.09).

CONCLUSIONS

At the 6-year follow-up, clinically significant clinical events did not differ between BiOSS stents and rDES.