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Significant left main coronary artery disease is a very high-risk subgroup of coronary artery disease that is a crucial indicator of heightened morbidity and mortality rates. Despite its clinical significance, uncertainties persist regarding the optimal management strategy for patients, particularly given its phenotypic variations. Existing evidence-based guidelines offer insights into revascularization options, yet questions remain regarding long-term prognoses and clinical outcomes when comparing percutaneous coronary intervention to coronary artery bypass grafting. This comprehensive review aims to provide an in-depth analysis of contemporary strategies for the diagnosis, assessment, and treatment of left main coronary artery disease. By synthesizing current literature and addressing the evolving landscape of revascularization modalities, this review seeks to contribute valuable insights for clinicians and researchers grappling with the complexities of managing left main coronary artery disease.
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This paper reports the effect of a magnetic field on plasma parameters and surface structuring of the Mg alloy after laser irradiation. Femtosecond pulses of a Ti:sapphire laser system (800 nm, 35 fs, 1 KHz) are employed as the source of irradiation at various irradiances ranging from 0.011P W/c m 2 to 0.117P W/c m 2 to generate ablated Mg-alloy plasma. A transvers magnetic field (TMF) of strength 1.1 Tesla is employed to confine laser generated Mg plasma. All the measurements are performed with and without TMF. The two plasma parameters, i.e., excitation temperature (T e x c ) and electron number density (n e) of Mg plasma, have been evaluated by laser-induced breakdown spectroscopy (LIBS) analysis. It is observed that the values of T e x c and n e of laser produced plasma (LPP) of the Mg alloy are higher in the presence of a magnetic field as compared to the field free case. Both show initially an increasing trend with increasing laser irradiance and after attaining their respective maxima a decreasing trend is observed with the further increase of irradiance. The magnetic confinement validity is confirmed by analytically evaluating thermal beta (ß t), directional beta (ß d), confinement radius (R b), and diffusion time (t d) for LPP of the Mg alloy. To correlate the LPP parameters of the Mg alloy with surface modifications a field emission scanning electron microscope (FE-SEM) analysis is performed. It was revealed that structures like laser-induced periodic surface structures (LIPSSs), agglomerates, islands, large sized bumps, along with channels and multiple ablative layers are observed. Distinct and well-defined surface structuring is observed in the presence of TMF as compared to the field free case. It is concluded that by applying an external magnetic field during laser irradiation, controlled material surface structuring is possible for fabrication of nanogratings and field emitters where spatial uniformity is critically important.
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BACKGROUND: Cardiac allograft vasculopathy (CAV) is associated with increased mortality in patients with orthotopic heart transplantation (OHT). In addition to immunosuppression, CAV can be treated with percutaneous coronary intervention (PCI) with drug eluting stents (DES) for focal lesions. There is a paucity of data on the rate of DES restenosis in patients with small vessel CAV. METHODS: This was a retrospective observational study of 101 coronary vessels treated with a DES diameter of 2.5 mm or less (small vessels) in 61 OHT patients compared to 72 coronary vessels treated with a DES diameter of >2.5 mm (large vessels) in 44 OHT patients at a single center between 2004 and 2022. Baseline demographic data, angiographic characteristics, and clinical outcomes were analyzed. RESULTS: At an average of 1.6 years after DES placement, follow-up angiography revealed in-stent restenosis in 36 (39 %) small vessel interventions and 11 (17 %) large vessel interventions (p = 0.003). Long term mortality did not differ between the groups (59 % vs 59 % at a median of 4.7 [IQR 2.4-7.8] years follow up). CONCLUSION: DES restenosis rates are high in small vessel CAV. Additional studies specifically examining PCI in small vessel CAV as well as the potential role for newer treatment strategies for CAV are warranted.