Assessment of Effectiveness of the Algorithm for Automated Quantitative Analysis of Metallic Strut Tissue Short-Term Coverage with Intravascular Optical Coherence Tomography.

Background: Due to its high resolution, optical coherence tomography (OCT) is the most suitable modality for neointimal coverage assessments. Evaluation of stent healing seems crucial to accurately define their safety profile since delayed healing is connected with stent thrombosis. This study aimed to present an algorithm for automated quantitative analysis of stent strut coverage at the early stages of vessel healing in intravascular OCT. Methods: A set of 592 OCT frames from 24 patients one month following drug-eluting stent implantation was used to assess the algorithm's effectiveness. Struts not covered on any side or covered but only on one side were categorized as uncovered. The algorithm consists of several key steps: preprocessing, vessel lumen segmentation, automatic strut detection, and measurement of neointimal thickness. Results: The proposed algorithm proved its efficiency in lumen and stent area estimation versus manual reference. It showed a high positive predictive value (PPV) (89.7%) and true positive rate (TPR) (91.4%) in detecting struts. A qualitative assessment for covered and uncovered struts was characterized by high TPR (99.1% and 80%, respectively, for uncovered and covered struts) and PPV (77.3% and 87%). Conclusions: The proposed algorithm demonstrated good agreement with manual measurements. Automating the stent coverage assessment might facilitate imaging analysis, which might be beneficial in experimental and clinical settings.

Sex Differences in Fractional Flow Reserve Utilization.

Background: The literature review shows that female patients are more frequently underdiagnosed or suffer from delayed diagnosis. Recognition of sex-related differences is crucial for implementing strategies to improve cardiovascular outcomes. We aimed to assess sex-related disparities in the frequency of fractional flow reserve (FFR)-guided procedures in patients who underwent angiography and/or percutaneous coronary intervention (PCI). Methods: We have derived the data from the national registry of percutaneous coronary interventions and retrospectively analyzed the data of more than 1.4 million angiography and/or PCI procedures [1,454,121 patients (62.54% men and 37.46% women)] between 2014 and 2022. The logistic regression analysis was conducted to explore whether female sex was associated with FFR utilization. Results: The FFR was performed in 61,305 (4.22%) patients and more frequently in men than women (4.15% vs. 3.45%, p < 0.001). FFR was more frequently assessed in females with acute coronary syndrome than males (27.75% vs. 26.08%, p < 0.001); however, women with chronic coronary syndrome had FFR performed less often than men (72.25% vs. 73.92%, p < 0.001). Females with FFR-guided procedures were older than men (69.07 (±8.87) vs. 65.45 (±9.38) p < 0.001); however. less often had a history of myocardial infarction (MI) (24.79% vs. 36.73%, p < 0.001), CABG (1.62% vs. 2.55%, p < 0.005) or PCI (36.6% vs. 24.79%, p < 0.001) compared to men. Crude comparison has shown that male sex was associated with a higher frequency of FFR assessment (OR = 1.2152-1.2361, p < 0.005). Conclusions: Despite a substantial rise in FFR utilization, adoption in women remains lower than in men. Female sex was found to be an independent negative predictor of FFR use.

Role of Lipid-Lowering and Anti-Inflammatory Therapies on Plaque Stabilization.

Atherosclerosis is the predominant underlying etiopathology of coronary artery disease. Changes in plaque phenotype from stable to high risk may spur future major adverse cardiac events (MACE). Different pharmacological therapies have been implemented to mitigate this risk. Over the last two decades, intravascular imaging modalities have emerged in clinical studies to clarify how these therapies may affect the composition and burden of coronary plaques. Lipid-lowering agents, such as statins, ezetimibe, and proprotein convertase subtilisin/kexin type 9 inhibitors, were shown not only to reduce low-density lipoprotein levels and MACE but also to directly affect features of coronary plaque vulnerability. Studies have demonstrated that lipid-lowering therapy reduces the percentage of atheroma volume and number of macrophages and increases fibrous cap thickness. Future studies should answer the question of whether pharmacological plaque stabilization may be sufficient to mitigate the risk of MACE for selected groups of patients with atherosclerotic coronary disease.

Importance of Short-Term Neointimal Coverage of Drug-Eluting Stents in the Duration of Dual Antiplatelet Therapy.

Dual antiplatelet therapy (DAPT) is mandatory after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation, but optimal DAPT duration remains a topic of intense discussion. The shorter regimen of DAPT might be especially beneficial for high-bleeding-risk (HBR) patients. Novel stent platforms have been designed with innovations that should facilitate vessel healing following stent implantation and enable short DAPT. This review aimed to summarize evidence of the neointimal coverage of short-term stents and their implications for DAPT duration. Results from histological and optical coherence tomography (OCT) studies confirm the significant role of uncovered struts after the implantation of a stent in patients presenting with late stent thrombosis. Several studies have shown favorable vessel healing at one month (with 83.2% of covered struts, on average) and three months following stent implantation (with 93.3% of covered struts, on average). Solely HBR patient trials have proven that one month of DAPT can be applicable and safe in this population. Three-month DAPT was tested in a more diverse population and remains effective and safe in comparison to a longer DAPT regimen. That evidence proves that short-term DAPT might be applicable, especially for HBR patients.

Robotic-Assisted Solutions for Invasive Cardiology, Cardiac Surgery and Routine On-Ward Tasks: A Narrative Review.

Robots are defined as programmable machines that can perform specified tasks. Medical robots are emerging solutions in the field of cardiology leveraging recent technological innovations of control systems, sensors, actuators, and imaging modalities. Robotic platforms are successfully applied for percutaneous coronary intervention, invasive cardiac electrophysiology procedures as well as surgical operations including minimally invasive aortic and mitral valve repair, coronary artery bypass procedures, and structural heart diseases. Furthermore, machines are used as staff-assisting tools to support nurses with repetitive clinical duties i.e., food delivery. High precision and resolution allow for excellent maneuverability, enabling the performance of medical procedures in challenging anatomies that are difficult or impossible using conventional approaches. Moreover, robot-assisted techniques protect operators from occupational hazards, reducing exposure to ionizing radiation, and limiting risk of orthopedic injuries. Novel automatic systems provide advantages for patients, ensuring device stability with optimized utilization of fluoroscopy. The acceptance of robotic technology among healthcare providers as well as patients paves the way for widespread clinical application in the field of cardiovascular medicine. However, incorporation of robotic systems is associated with some disadvantages including high costs of installation and expensive disposable instrumentations, the need for large operating room space, and the necessity of dedicated training for operators due to the challenging learning curve of robotic-assisted interventional systems.

Revascularization in Ischemic Heart Failure with Reduced Left Ventricular Ejection Fraction.

PURPOSE OF REVIEW: Coronary artery disease (CAD) is estimated to account for over 60% of heart failure (HF) patients and is associated with worse outcomes than a non-ischemic etiology. In patients with ischemic HF, myocardial revascularization has multiple mechanisms of action based on the concept that blood flow restoration of viable but underperfused myocardium might reverse the hibernation of the left ventricle and prevent future spontaneous myocardial infarction, which could potentially improve patients' outcomes. Here, we aim to elaborate on indications, timing, type, and impact of completeness of revascularization in patients with heart failure with reduced ejection fraction (HFrEF) and ischemic etiology. RECENT FINDINGS: For decades, coronary artery bypass graft surgery has been the pilar of revascularization in patents with multivessel CAD and reduced EF. Recent development in the interventional field led to overall increase of percutaneous coronary intervention (PCI) adoption in treatment of ischemic HFrEF. However, recently published randomized study demonstrated no added benefit of PCI over optimal medical therapy in patients with severe ischemic cardiomyopathy challenging the beneficial role of revascularization in this setting. Since the decision on revascularization in ischemic cardiomyopathy frequently cannot be made based strictly on guidelines, tailored treatment strategy should be mandated with the essential role of multidisciplinary approach. These decisions should be based on capability to achieve complete revascularization, with the consideration that in certain situations it may not be accomplished.

Impact of smoking on outcomes in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention.

INTRODUCTION: Smoking is a well­established risk factor for cardiovascular diseases. However, in patients with ST­segment elevation myocardial infarction (STEMI), smoking has been associated with better clinical outcomes; this phenomenon became known as the "smoker's paradox." OBJECTIVES: The aim of this study was to evaluate the association between smoking and clinical outcomes in STEMI patients treated with primary percutaneous coronary intervention (PCI), using 3 large national registries. PATIENTS AND METHODS: We retrospectively analyzed the data of 82 235 hospitalized STEMI patients treated with primary PCI. Among the analyzed population, 30 966 patients (37.96%) were smokers, and 51 269 (62.36%) were nonsmokers. We evaluated the baseline characteristics, pharmacotherapy, clinical outcomes, and readmission causes in a 36­month follow­up. RESULTS: The smokers were significantly younger (median [interquartile range] age, 58 [52-64] vs 68 [59-77] years; P <0.001) than the nonsmokers, and there were more men in this group. The patients who smoked were less likely to have traditional risk factors, as compared with the nonsmokers. In the unadjusted analysis, in­hospital and 36­month mortality and rehospitalization rates were lower in the smokers group. However, after adjustment for baseline characteristics that differed between the 2 groups, the multivariable analysis showed that tobacco use was one of the independent risk factors for 36­month mortality (hazard ratio, 1.11; 95% CI, 1.06-1.18; P <0.001). CONCLUSIONS: In the present large­scale, registry­based analysis, the observed lower 36­month crude rates of adverse events among the smokers, as compared with the nonsmokers, might be partially explained by a significantly lower burden of traditional risk factors and younger age of the smokers. After accounting for age and other baseline differences, smoking was found to be one of the independent risk factors for 36­month mortality.

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.

Morphological characteristics of lesions with thin cap fibroatheroma-a substudy from the COMBINE (OCT-FFR) trial.

AIMS: To study if any qualitative or quantitative optical coherence tomography (OCT) variables in combination with thin cap fibroatheroma (TCFA) patients could improve the identification of lesions at risk for future major adverse cardiac events (MACEs). METHODS AND RESULTS: From the combined optical coherence tomography morphologic and fractional flow reserve hemodynamic assessment of non- culprit lesions to better predict adverse event outcomes in diabetes mellitus patients: COMBINE (OCT-FFR) trial database (NCT02989740), we performed a detailed assessment OCT qualitative and quantitative variables in TCFA carrying diabetes mellitus (DM) patients with vs. without MACE during follow-up. MACEs were defined as a composite of cardiac death, target vessel myocardial infarction, clinically driven target lesion revascularization, and hospitalization for unstable angina. From the 390 fractional flow reserve (FFR)-negative DM patients, 98 (25.2%) had ≥1 OCT-detected TCFA, of which 13 (13.3%) had MACE and 85 (86.7%) were event-free (non-MACE). The baseline characteristics were similar between both groups; however, a smaller minimal lumen area (MLA) and lower mean FFR value were observed in MACE group (1.80 vs. 2.50 mm2, P = 0.01, and 0.85 vs. 0.89, P = 0.02, respectively). Prevalence of healed plaque (HP) was higher in the MACE group (53.85 vs. 21.18%, P = 0.01). TCFA were predominantly located proximal to the MLA. TCFA area was smaller in the MACE group, while no difference was observed regarding the lesion area. CONCLUSION: Within TCFA carrying patients, a smaller MLA, lower FFR values, and TCFA location adjacent to a HP were associated with future MACE. Carpet-like measured lesion area surface was similar, while the TCFA area was smaller in the MACE arm, and predominantly located proximal to the MLA.

Long-term outcomes of patients with normal fractional flow reserve and thin-cap fibroatheroma.

BACKGROUND: The long-term prognostic implications of fractional flow reserve (FFR)-negative lesions hosting vulnerable plaques remain unsettled. AIMS: The aim of this study was to evaluate the association of non-ischaemic lesions hosting optical coherence tomography (OCT)-detected thin-cap fibroatheromas (TCFA) with first and recurrent cardiovascular events during follow-up up to 5 years in a diabetes mellitus (DM) patient population. METHODS: COMBINE OCT-FFR is a prospective, international, double-blind, natural history study. Patients with DM and with ≥1 FFR-negative lesion were classified into 2 groups based on the presence or absence of ≥1 TCFA lesion. The primary endpoint (PE) is a composite of cardiac mortality, target vessel-related myocardial infarction (TV-MI), clinically driven target lesion revascularisation (TLR), or unstable angina (UA) requiring hospitalisation during follow-up up to 5 years. RESULTS: Among 390 DM patients (age 67.5±9 years; 37% female) with ≥1 FFR-negative lesion, 292 (74.9%) were TCFA-negative while 98 (25.1%) were TCFA-positive. The PE occurred more frequently in TCFA-positive than in TCFA-negative patients (21.4% vs 8.2%, hazard ratio [HR] 2.89, 95% confidence interval [CI]: 1.61-5.20; p<0.001; 6.42 vs 2.46 events per 100 patient-years, rate ratio [RR] 2.61, 95% CI: 1.38-4.90; p=0.002). Furthermore, when TV-MI, TLR, and UA were treated as recurrent components of the PE, TCFA-positive patients experienced a higher risk of recurrent events (HR 2.89, 95% CI; 1.74-4.80; p<0.001; 13.45 vs 2.87 events per 100 patient-years, RR 4.69, 95% CI: 2.86-7.83; p<0.001). A multivariable analysis identified the presence of TCFA as an independent predictor of the PE (HR 2.76, 95% CI: 1.53-4.97; p<0.001). CONCLUSIONS: OCT-detected TCFA-positive lesions, although not ischaemia-generating, are associated with an increased risk of adverse events during long-term follow-up. CLINICALTRIALS: gov: NCT02989740.

Underlying Causes of Myocardial Infarction with Nonobstructive Coronary Arteries: Optical Coherence Tomography and Cardiac Magnetic Resonance Imaging Pilot Study.

BACKGROUND: Scientific statements recommend multimodality imaging in myocardial infarction with non-obstructive coronary arteries (MINOCA) to define the underlying cause. AIM: We evaluated the diagnostic yield of intravascular optical coherence tomography (OCT) and cardiac magnetic resonance (CMR) in the MINOCA setting. METHODS: In this prospective, single center, observational pilot study, we enrolled patients with MINOCA without previous coronary interventions. All patients underwent three vessel OCT, followed by CMR. Imaging results were combined to determine the mechanism of MINOCA, when possible. RESULTS: We enrolled 10 patients in this pilot study. Women constituted 50% of the analyzed population. The mean age of patients was 52 years. ST-segment elevation was found in 30% of patients. A possible culprit lesion was identified by OCT in 70% of participants, most commonly plaque rupture or erosion. An ischemic pattern of CMR abnormalities was identified in 70% of participants. Myocarditis and Tako-Tsubo were identified in 30%. A cause of MINOCA was identified in all patients using multimodality imaging, while using OCT alone identification occurred in only 70% of patients. CONCLUSION: In this pilot study, multimodality imaging with OCT and CMR identified potential mechanisms in all patients with a diagnosis of MINOCA, and it has the potential to guide medical therapy for secondary prevention.

Gel Point Determination in Resin Transfer Molding Process with Fiber Bragg Grating Inscribed in Side-Hole Elliptical Core Optical Fiber.

Material as well as process variations in the composites industry are reasons to develop methods for in-line monitoring, which would increase reproducibility of the manufacturing process and the final composite products. Fiber Bragg Gratings (FBGs) have shown to be useful for monitoring liquid-composite molding processes, e.g., in terms of online gel point detection. Existing works however, focus on in-plane strain measurements while out-of-plane residual strain prevails. In order to measure out-of-plane strain, FBG inscribed in highly birefringent fiber (HB FBG) can be used. The purpose of this research is the cure stage detection with (a) FBG inscribed in single mode and (b) FBG inscribed in highly-birefringent side-hole fiber in comparison to the reference gel point detected with an in-mold DC sensor. Results reveal that the curing process is better traceable with HB FBG than with regular FBG. Thus, the use of HB FBG can be a good method for the gel point estimation in the RTM process.

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.

Thin-Cap Fibroatheroma Rather Than Any Lipid Plaques Increases the Risk of Cardiovascular Events in Diabetic Patients: Insights From the COMBINE OCT-FFR Trial.

BACKGROUND: Autopsy studies have established that thin-cap fibroatheromas (TCFAs) are the most frequent cause of fatal coronary events. In living patients, optical coherence tomography (OCT) has sufficient resolution to accurately differentiate TCFA from thick-cap fibroatheroma (ThCFA) and not lipid rich plaque (non-LRP). However, the impact of OCT-detected plaque phenotype of nonischemic lesions on future adverse events remains unknown. Therefore, we studied the natural history of OCT-detected TCFA, ThCFA, and non-LRP in patients enrolled in the prospective multicenter COMBINE FFR-OCT trial (Combined Optical Coherence Tomography Morphologic and Fractional Flow Reserve Hemodynamic Assessment of Non-Culprit Lesions to Better Predict Adverse Event Outcomes in Diabetes Mellitus Patients). METHODS: In the COMBINE FFR-OCT trial, patients with diabetes and ≥1 lesion with a fractional flow reserve >0.80 underwent OCT evaluation and were clinically followed for 18 months. A composite primary end point of cardiac death, target vessel-related myocardial infarction, target-lesion revascularization, and hospitalization for unstable angina was evaluated in relation to OCT-based plaque morphology. RESULTS: A total of 390 patients (age 67.5±9 years; 63% male) with ≥1 nonischemic lesions underwent OCT evaluation: 284 (73%) had ≥1 LRP and 106 (27%) non-LRP lesions. Among LRP patients, 98 (34.5%) had ≥1 TCFA. The primary end point occurred in 7% of LRP patients compared with 1.9% of non-LRP patients (7.0% versus 1.9%; hazard ratio [HR], 3.9 [95% CI, 0.9-16.5]; P=0.068; log rank-P=0.049). However, within LRP patients, TCFA patients had a much higher risk for primary end point compared with ThCFA (13.3% versus 3.8%; HR, 3.8 [95% CI, 1.5-9.5]; P<0.01), and to non-LRP patients (13.3% versus 1.9%; HR, 7.7 [95% CI, 1.7-33.9]; P<0.01), whereas ThCFA patients had risk similar to non-LRP patients (3.8% versus 1.9%; HR, 2.0 [95% CI, 0.42-9.7]; P=0.38). Multivariable analyses identified TCFA as the strongest independent predictor of primary end point (HR, 6.79 [95% CI, 1.50-30.72]; P=0.013). CONCLUSIONS: Among diabetes patients with fractional flow reserve-negative lesions, patients carrying TCFA lesions represent only one-third of LRP patients and are associated with a high risk of future events while patients carrying LRP-ThCFA and non-LRP lesions portend benign outcomes. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02989740.

Intravascular Lithotripsy for the Treatment of Stent Underexpansion: The Multicenter IVL-DRAGON Registry.

Background: Whereas the efficacy and safety of intravascular lithotripsy (IVL) have been confirmed in de novo calcified coronary lesions, little is known about its utility in treating stent underexpansion. This study aimed to investigate the impact of IVL in treating stent underexpansion. Methods and Results: Consecutive patients with stent underexpansion treated with IVL entered the multicenter IVL-Dragon Registry. The procedural success (primary efficacy endpoint) was defined as a relative stent expansion >80%. Thirty days device-oriented composite endpoint (DOCE) (defined as a composite of cardiac death, target lesion revascularization, or target vessel myocardial infarction) was the secondary endpoint. A total of 62 patients were enrolled. The primary efficacy endpoint was achieved in 72.6% of patients. Both stent underexpansion 58.5% (47.5−69.7) vs. 11.4% (5.8−20.7), p < 0.001, and the stenotic area 82.6% (72.4−90.8) vs. 21.5% (11.1−37.2), p < 0.001, measured by quantitative coronary angiography improved significantly after IVL. Intravascular imaging confirmed increased stent expansion following IVL from 37.5% (16.0−66.0) to 86.0% (69.2−90.7), p < 0.001, by optical coherence tomography and from 57.0% (31.5−77.2) to 89.0% (85.0−92.0), p = 0.002, by intravascular ultrasound. Secondary endpoint occurred in one (1.6%) patient caused by cardiac death. There was no target lesion revascularization or target vessel myocardial infarction during the 30-day follow-up. Conclusions: In this real-life, largest-to-date analysis of IVL use to manage underexpanded stent, IVL proved to be an effective and safe method for facilitating stent expansion and increasing luminal gain.

'Ref! Could You Help Me?'-Building a Positive Climate by Referees during Floorball Competitions in Youth Sport.

In creating a positive climate in sport for children and youth, the role of adults is of key importance as their behavior and attitudes determine the experiences and multilateral development of young players. Relatively recently, the importance of the referee in creating a supportive sporting environment has begun to be emphasized. This concerns, in particular, team sports in which the referees interact with players many times and influence the course of the game. The aim of the study was to evaluate the quality of the referee-players' interactions during youth floorball matches in terms of building a positive climate and responsiveness to the players' needs. Another aim of the study was to examine whether the referee's qualifications and players' gender affect the quality of their interactions with the players. The study was conducted among 21 referees officiating matches for girls and boys aged 12-18. Naturalistic and structured observation methods were used in the study. The observation was conducted using a wireless intercom that allows listening to verbal messages directed to the players. Furthermore, the referee's work was recorded using a camera. The results of the statistical tests did not show any significant differences in the assessment of referees between the groups distinguished in terms of the referees' license and players' gender in both examined dimensions. The observations showed that the average rating of building a positive climate by referees during a sporting event measured on a seven-point scale was 'poor' (2.81 pts). The referees were assessed significantly higher on the second dimension (responsiveness to the players' needs), although an overall rating of 3.81 pts means a medium level of interaction quality. The results indicate areas in which referees can improve. They lead to the following conclusions: (i) the contents of training for floorball referees should include problems of pedagogy and developmental psychology; (ii) referees should be equipped with appropriate competencies for building a positive climate during matches and monitoring the players' needs; (iii) referees appointed to officiate children and youth games should be characterized by appropriate predispositions.