Rationale and design of the randomized, multicenter, open-label, controlled POLBOS 3 trial aimed to compare regular drug-eluting stents versus the dedicated coronary bifurcation sirolimus-eluting BiOSS LIM C stent

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).

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.