Optimal lesion preparation before implantation of a Magmaris bioresorbable scaffold in patients with coronary artery stenosis: Rationale, design and methodology of the OPTIMIS study.

Introduction: Percutaneous coronary intervention with implantation of a bioresorbable scaffold (BRS) provide the vessel support for a limited period allowing the vessel to restore normal vasomotion after degradation of the BRS, opposed to treatment with drug-eluting stents where the metal persist in the vessel wall. Late lumen loss and reduction in lumen area after implantation have been reported. The purpose of this study was to investigate whether intense pre-dilatation before BRS implantation resulted in less reduction of minimal lumen area at 6- and 12-month follow-up after implantation of a Magmaris BRS (MgBRS). Coronary imaging with optical coherence tomography (OCT) and intravascular ultrasound (IVUS) was assessed to track changes in lumen and vessel dimensions. Methods: The prospective Optimal lesion PreparaTion before Implantation of the Magmaris bioresorbable scaffold In patients with coronary artery Stenosis (OPTIMIS) study randomly assigned eighty-two patients with chronic coronary syndrome to two pre-dilatation treatment strategies. Patients were randomized in a 1:1 ratio to pre-dilatation with either a non-compliant scoring balloon or a standard non-compliant balloon prior to implantation of a MgBRS. The treated segment was evaluated with OCT and IVUS at baseline, after 6 and 12 months to assess changes in lumen and vessel dimensions. The hypothesis was that more intense pre-dilatation with a non-compliant scoring balloon before MgBRS implantation can reduce the risk of late lumen reduction compared to standard pre-dilatation. The power calculation used expected MLA after 6 months (6.22 mm2 for the scoring balloon and 5.01 mm2 for the standard non-compliant balloon), power of 80 %, significance level of 0.05 and expected drop-out rate of 15 %, requiring 82 patients to be enrolled. Results: Eighty-two patients were included in the study. Enrollment was from December 2020 to September 2023. Conclusion: The hypothesis was that more intense pre-dilatation with a non-compliant scoring balloon before MgBRS implantation can reduce the risk of late lumen reduction compared to standard pre-dilatation.

Long-term outcomes after coronary intervention with biodegradable polymer stents in patients with acute coronary syndromes.

BACKGROUND: Patients with acute coronary syndromes (ACS) may have worse outcomes after percutaneous coronary intervention compared to patients without ACS. AIMS: To compare 5-year efficacy and safety outcomes in patients with and without ACS treated with biodegradable polymers, the ultrathin strut sirolimus-eluting Orsiro stent (O-SES) or the biolimus-eluting Nobori stent (N-BES). METHODS: The Scandinavian Organisation for Randomized Trials with Clinical Outcome VII is a randomized trial comparing O-SES and N-BES in an all-comer setting. Of 2525 patients, 1329 (53%) patients had ACS and 1196 (47%) patients were without ACS. Endpoints were target lesion failure (TLF) (a composite of cardiac death, target lesion myocardial infarction, or target lesion revascularization) and definite stent thrombosis within 5 years. RESULTS: At 5-year follow-up, TLF did not differ significantly between patients with and without ACS (12.3% vs. 13.2%; rate ratio (RR) 1.00; 95% confidence interval (CI): 0.70-1.44), whereas the risk of definite stent thrombosis was increased in patients with ACS (2.3% vs. 1.3; RR: 2.01 [95% CI: 1.01-3.98]). In patients with ACS, the rate of TLF was similar between O-SES and N-BES (12.4% vs. 12.3%; RR: 1.02; 95% CI: 0.74-1.40). The reduced risk of definite stent thrombosis in O-SES treated ACS patients within the first year (0.2% vs. 1.6%; RR: 0.12; 95% CI: 0.02-0.93) was not maintained after 5 years (1.8% vs. 2.7%; RR: 0.77; 95% CI: 0.37-1.63). CONCLUSION: Patients with ACS had an increased risk of stent thrombosis regardless of the stent type used. Long-term outcomes were similar for ACS patients treated with O-SES or N-BES at 5 years.

The Influence of Microcirculatory Dysfunction on the Resting Full Cycle Ratio Compared to Fractional Flow Reserve.

BACKGROUND: The relation between the resting full cycle ratio (RFR) and fractional flow reserve (FFR) is not fully understood. This study aims to investigate the influence of coronary microvascular dysfunction, assessed by the index of microvascular resistance (IMR), on RFR compared to FFR in patients undergoing functional assessment for coronary stenosis. MATERIALS AND METHODS: Two-hundred patients with borderline stenosis underwent functional assessment of RFR, FFR, coronary flow reserve (CFR) and IMR. Retriever operator curve analysis was performed to assess the diagnostic value of RFR in patients with (IMR ≥ 24) and (IMR < 24). RESULTS: Median RFR did not differ significantly in patients with IMR ≥ 24 compared to patients with IMR < 24: 0.89 (interquartile range (IQR) 0.84, 0.95) vs. 0.90 (IQR 0.84, 0.92), p = 0.29). FFR was significantly higher in patients with IMR ≥ 24 compared to patients with IMR < 24: median FFR 0.85 (IQR (0.76, 0.92)) vs. 0.82 (IQR 0.73, 0.86), p = 0.009, and median CFR was significantly lower 1.80 (IQR 1.40, 2.55) vs. 2.70 (IQR 1.80, 3.95), p < 0.001. The diagnostic value of RFR was high (Area under the curve (AUC) 0.89 95 % Confidence Interval: [0.85, 0.93]) and AUC did not differ between patients with IMR ≥ 24 compared to patients with IMR < 24: 0.89 vs. 0.90, p = 0.89. An overall optimal cut off of 0.88 was identified. The cut off did not differ significantly between patients with IMR ≥ 24 compared to patients with IMR < 24: 0.88 vs. 0.90, p = 0.397. CONCLUSION: In patients with coronary borderline stenosis, the coronary microvascular function did not influence on the cut off values or AUC of RFR compared to FFR.

Five-Year Clinical Outcome of the Biodegradable Polymer Ultrathin Strut Sirolimus-Eluting Stent Compared to the Biodegradable Polymer Biolimus-Eluting Stent in Patients Treated With Percutaneous Coronary Intervention: From the SORT OUT VII Trial.

BACKGROUND: Biodegradable polymer drug-eluting stents were developed to improve safety and efficacy outcomes for patients undergoing percutaneous coronary intervention. However, few long-term follow-up efficacy studies are available. The study sought to investigate 5-year results from the SORT OUT VII trial (Scandinavian Organization for Randomized Trials With Clinical Outcome) comparing the biodegradable polymer ultrathin-strut sirolimus-eluting Orsiro stent (O-SES) versus the biodegradable polymer biolimus-eluting Nobori stent (N-BES). METHODS: This registry-based, randomized, multicenter, single-blinded, noninferiority trial compared O-SES and N-BES in an all-comer population. The composite primary end point, target lesion failure, consisted of cardiac death, myocardial infarction related to the target lesion, or target lesion revascularization within 1 year. Follow-up was extended to 5 years. RESULTS: Five-year follow-up was completed for 2521 patients (99.8%). Five-year target lesion failure did not differ between O-SES (12.4%) and N-BES (13.1%; rate ratio [RR], 0.94 [95% CI, 0.75-1.18]). Cardiac death (RR, 0.95 [95% CI, 0.67-1.34]), target myocardial infarction (RR, 1.14 [95% CI, 0.76-1.71]), target lesion revascularization (RR, 0.90 [95% CI, 0.67-1.21]), and definite stent thrombosis rates (RR, 0.73 [95% CI, 0.41-1.33]) did not differ significantly between the 2 stents. Within the first year, definite ST was significantly lower for O-SES (0.4%) compared to N-BES (1.2%; RR, 0.33 [95% CI, 0.12-0.92]), but no difference was from 1 through 5 years: O-SES 1.2% and N-BES 0.9% (RR, 1.28 [95% CI, 0.58-2.82]). CONCLUSIONS: Five years after treatment with biodegradable polymer stents, target lesion failure did not differ among O-SES and N-BES. Definite stent thrombosis was less often seen within the first year in the O-SES but the difference was not maintained after 5 years. REGISTRATION: URL: https://clinicaltrials.gov; Unique identifier: NCT01879358.

Impact of diabetes on long-term all-cause re-hospitalization after revascularization with percutaneous coronary intervention.

PURPOSE: The purpose of the study was to investigate the incidence, cause and probability of re-hospitalization within 30 and 365 days after percutaneous coronary intervention (PCI) in patients with diabetes. METHOD: Between January 2010 and September 2014, 2763 patients with diabetes were treated with PCI at two Hospitals in Western Denmark. Reasons for readmission within 30 and 365 days were identified. RESULTS: Readmission risks for patients with diabetes were 58% within 365 days and 18% within 30 days. Reason for readmission was ischemic heart disease (IHD) in 725 patients (27%), and non-IHD-related reasons in 826 patients (31%). IHD-related readmission within 365 days was associated with female gender (OR 1.3, 95% CI: 1.1-1.5), and non-ST-segment elevation myocardial infarction, compared to stable angina at the index hospitalization (OR 1.3, 95% CI: 1.1-1.6). Among patients with diabetes, increased risk of readmission due to other reasons were age (OR 1.3, 95% CI: 1.2-1.5) and higher scores of modified Charlson Comorbidity index (CCI): CCI ≥3 (OR 3.6, 95% CI: 2.8-4.6). CONCLUSION: More than half of the patients with diabetes mellitus undergoing PCI were readmitted within 1 year. Comorbidities were the strongest predictor for non-IHD-related readmission, but did not increase the risk for IHD-related readmissions.

Early vascular healing after implantation of the polymer-free biolimus-eluting stent or the ultrathin strut biodegradable polymer sirolimus-eluting stent in patients with ST-segment elevation myocardial infarction.

OBJECTIVE: To evaluate the difference in early vascular healing between the ultrathin-strut biodegradable-polymer sirolimus-eluting Orsiro stent (O-SES) and the polymer-free biolimus-A9-eluting BioFreedom stent (BF-BES), assessed with optical coherence tomography (OCT) after primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarctions (STEMIs). METHODS: Eighty patients with STEMI who underwent primary PCI were randomly allocated 1:1 to treatment with BF-BES or O-SES. OCT was acquired after PCI and at 1-month follow-up. The primary endpoint was 1-month OCT-assessed vascular healing index based on the presence of uncovered and malapposed stent struts and intraluminal filling defects where low vascular healing index indicated favorable vascular healing. RESULTS: At 1-month, the vascular healing index was similar in O-SES 11.5 [interquartile range (IQR) 9.5-17.5], compared to BF-BES 11.5 (IQR 7.1-12.5; P = 0.14). Percentage of uncovered struts [O-SES 31.5% (IQR 20.7-41.9), P = 0.43] vs. BF-BES 27.8% (IQR 19.4-41.9; P = 0.44), and median volume of neointimal hyperplasia [O-SES 4.9 mm3 (IQR 1.4-13.1) vs. BF-BES 7.1 mm3 (IQR 2.8-17.0), P = 0.18] did not differ significantly between the two stent groups. Complete coverage was not observed in any of the stents. The percentages of stents with malapposition did not differ significantly (O-SES 87.1% vs. BF-BES 71.4%, P = 0.14) whereas percentage of malapposed struts [O-SES 3.5% (IQR 0.8-5.5) vs. BF-BES 0.8% (IQR 0.0-1.8), P = 0.003] was lower in the BF-BES group. CONCLUSION: In patients with STEMI, the drug-coated BF-BES and the thin strut O-SES had similar vascular healing index at 1-month. However, the thin O-SES struts were more often malapposed.

Optical Coherence Tomography- Versus Angiography-Guided Magnesium Bioresorbable Scaffold Implantation in NSTEMI Patients.

BACKGROUND: The purpose of a bioresorbable scaffold (BRS) is to provide radial support during coronary healing. In this study, coronary artery healing after optical coherence tomography (OCT)- versus angiography-guided magnesium BRS (MBRS) implantation in patients with non-ST-segment-elevation myocardial infarction (NSTEMI) is compared. METHODS: 75 patients were randomized 1:1 to OCT- or angiography-guided implantation of a MBRS with protocolled pre- and post-dilation. In the OCT-guided group, prespecified criteria indicating additional intervention were (1) scaffold under-expansion, (2) strut malapposition, (3) edge dissection, and (4) residual stenosis at distal or proximal reference segments. The primary endpoint was OCT-derived healing stage at 6 months. RESULTS: At 6 months, there was no difference in average healing stage between OCT- and angiography-guided intervention (4.6 [interquartile range (IQR): 4.5-4.7] versus 4.5 [IQR: 4.3-4.7]; p = 0.54). The MBRSs were completely resolved in 77.0% [IQR: 68.5-85.5] versus 76.5% [IQR: 67.9-85.5]; (p = 0.97). Minimal lumen area (MLA) was reduced at 6 months in both the OCT- (32.3%; p < 0.01) and the angiography-guided group (21.3%; p < 0.01), however OCT-guided implantation was associated with a greater reduction of total lumen volume (-27.1 ± 32.5 mm3 versus -5.0 ± 32.9 mm3; p < 0.01) and MLA (-2.3 ± 1.6 mm2 vs. -1.4 ± 1.4 mm2; p = 0.02). CONCLUSIONS: In NSTEMI patients, OCT-guidance with protocolled pre- and post-dilation of MBRS implantation showed similar healing pattern at 6 months compared to angiography-guidance alone. CLINICAL TRIAL REGISTRATION: The Coronary Artery Healing Process after Optical Coherence Tomography Guided Percutaneous Coronary Intervention with Magmaris Bioresorbable Scaffold in Patients with Non-ST-Segment-Elevation Myocardial Infarction: (HONEST) trial is registered with ClinicalTrials.gov, NCT03016624.

Coronary Artery Healing Process after Bioresorbable Scaffold in Patients with Non-ST-Segment Elevation Myocardial Infarction: Rationale, Design, and Methodology of the HONEST Study.

BACKGROUND: Bioresorbable scaffolds (BRSs) is a relatively new approach in treating coronary artery stenosis. The initial results of the first commercially available scaffolds consisting of a backbone of poly-L-lactide raised safety concerns related to delayed resorption and healing. The magnesium alloy-based scaffold degrades via bio-corrosion within months, whereas it often takes several years for polymer scaffolds to degrade. The aim of the study was to assess the healing stage by optical coherence tomography (OCT) after 6 months in patients with non-ST-segment elevation myocardial infarct (NSTEMI) randomized to OCT or angiography-guided percutaneous coronary intervention with implantation of a magnesium sirolimus-eluting Magmaris scaffold (Magmaris; Biotronik, Bülach, Switzerland). METHODS: We analyzed the healing process by comparing OCT at baseline and after 6 months. Five stages of healing were defined with stage 1 being the least healed and stage 5 demonstrating complete resorption and healing with no visible scaffold/remnant. The primary end point is a calculated healing score that is based on 5 subtypes of healing stage: (1) malapposed, (2) uncovered with no detection of smooth surface tissue on top of struts or remnants, (3) covered protruding, (4) covered embedded, and (5) complete healing with a smooth neointimal surface and no sign of struts or visible remnants assessed by OCT 6 months after the index procedure. RESULTS: The impact of OCT-guided compared to angiography-guided scaffold implantation will be illuminated. CONCLUSION: The present study will provide new information on midterm healing properties of the magnesium BRS in patients with NSTEMI.

Influence of Plaque Characteristics on Early Vascular Healing in Patients With ST-Elevation Myocardial Infarction.

OBJECTIVES: To compare the early vascular healing of ruptured plaques (RP) and non-ruptured plaques (NRP) one month after primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI), using optical coherence tomography (OCT). BACKGROUND: Vascular healing and strut coverage are important factors in reducing the risk of stent thrombosis after PCI. Influence of underlying lesion characteristics and differences in healing response between RP and NRP are unknown. METHODS: Twenty-six STEMI-patients underwent PCI and implantation of a polymer-free drug-coated Biofreedom stent (BF-BES). OCT was performed pre-PCI, post-PCI and at 1-month follow-up. The patients were divided into two groups: RP = 15 and NRP = 11. OCT analyses of culprit lesion, post stent implantation at baseline and follow-up were performed to determine the difference in vascular healing based on presence of uncovered and/or malapposed stent struts and intraluminal filling defects. RESULTS: The stent coverage did not differ significantly between the two groups at 1-month follow-up with percentage of uncovered struts: RP 26.5% [IQR 15.0-49.0] and NRP 28.1% [IQR 15.5-38.8] for NRP (p = 0.78). At 1-month, RP showed an increased percentage of late acquired malapposed struts (1.4% [IQR 0.8-2.4] vs. 0.0% [IQR 0.0-1.4], p = 0.03) and a larger total malapposition area (1.3 mm2 [IQR 0.4-2.5] vs. 0.0 mm2 [IQR 0.0-0.9], p = 0.01), compared to NRP. CONCLUSION: Three out of four struts were covered within one month after stenting. The vascular healing was comparable in RP and NRP on stent coverage. However, RP had more and larger late acquired malapposition areas.

Lipid-core burden response to stent implantation assessed with near-infrared spectroscopy and intravascular ultrasound evaluation in patients with myocardial infarction.

INTRODUCTION: Near-infrared spectroscopy (NIRS) is a new method to identify lipid core plaque (LCP). The LCP and vascular response were assessed with NIRS to examine whether LCP was compressed or redistributed during percutaneous coronary intervention with stent implantation. METHODS: In 25 patients with non-ST segment elevation myocardial infarction (NSTEMI) NIRS acquisition was performed after predilation, stent implantation with nominal pressure and high-pressure post-dilation with a non-compliant balloon. The intravascular ultrasound (IVUS) measures included volumes of external elastic membrane (EEM), lumen and plaque+media. The NIRS measures included lipid core burden index (LCBI) and maximum value of LCBI for any of the 4-mm segment (maxLCBI4mm). RESULTS: From predilation to stent implantation and post-dilation EEM volume increased from 337±124mm3 to 369±136mm3 and to 397±144mm3 (p<0.001), while plaque volume decreased from 225±84mm3 to 202±85mm3 and to 192±81mm3 (p<0.001). Plaque shift to the proximal reference segment was found in 40% of the lesions. The maxLCBI4mm decreased significantly from predilation to stent implantation (492±235 to 208±193 (p<0.001), whereas post dilation did not cause any further significant reduction. Also LCBI decreased significantly from predilation to stent implantation (173±103 to 68±67, p<0.001), without any further significant reduction during post-dilation. The LCBI did neither in the proximal nor in the distal reference segments change significantly during stent implantation or post-dilation. CONCLUSION: Lumen enlargement was caused by vessel expansion, plaque compression and longitudinally plaque redistribution. Lipid-core burden at the stented segment was decreased.