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Background and Aims Survivors of acute coronary syndromes face an elevated risk of recurrent atherosclerosis-related vascular events despite advanced medical treatments. The underlying causes remain unclear. This study aims to investigate whether myocardial infarction (MI)-induced trained immunity in monocytes could sustain proatherogenic traits and expedite atherosclerosis. Methods Apolipoprotein-E deficient (ApoE−/−) mice and adoptive bone marrow transfer chimeric mice underwent MI or myocardial ischaemia–reperfusion (IR). A subsequent 12-week high-fat diet (HFD) regimen was implemented to elucidate the mechanism behind monocyte trained immunity. In addition, classical monocytes were analysed by flow cytometry in the blood of enrolled patients. Results In MI and IR mice, blood monocytes and bone marrow-derived macrophages exhibited elevated spleen tyrosine kinase (SYK), lysine methyltransferase 5A (KMT5A), and CCHC-type zinc finger nucleic acid-binding protein (CNBP) expression upon exposure to a HFD or oxidized LDL (oxLDL) stimulation. MI-induced trained immunity was transmissible by transplantation of bone marrow to accelerate atherosclerosis in naive recipients. KMT5A specifically recruited monomethylation of Lys20 of histone H4 (H4K20me) to the gene body of SYK and synergistically transactivated SYK with CNBP. In vivo small interfering RNA (siRNA) inhibition of KMT5A or CNBP potentially slowed post-MI atherosclerosis. Sympathetic denervation with 6-hydroxydopamine reduced atherosclerosis and inflammation after MI. Classical monocytes from ST-elevation MI (STEMI) patients with advanced coronary lesions expressed higher SYK and KMT5A gene levels. Conclusions The findings underscore the crucial role of monocyte trained immunity in accelerated atherosclerosis after MI, implying that SYK in blood classical monocytes may serve as a predictive factor for the progression of atherosclerosis in STEMI patients. [ABSTRACT FROM AUTHOR]

Lipoprotein(a) (Lp[a]) is associated with an increased risk of myocardial infarction (MI). However, the mechanism underlying this association has yet to be fully elucidated. This multicenter study aimed to investigate whether association between Lp(a) and MI risk is reinforced by the presence of low-attenuation plaque (LAP) identified by coronary computed tomography angiography (CCTA). In a derivation cohort, a total of 5,607 patients with stable chest pain suspected of coronary artery disease who underwent CCTA and Lp(a) measurement were prospectively enrolled. In validation cohort, 1,122 patients were retrospectively collected during the same period. High Lp(a) was defined as Lp(a) ≥50 mg/dL. The primary endpoint was a composite of time to fatal or nonfatal MI. Associations were estimated using multivariable Cox proportional hazard models. During a median follow-up of 8.2 years (Q1-Q3: 7.2-9.3 years), the elevated Lp(a) levels were associated with MI risk (adjusted HR [aHR]: 1.91; 95% CI: 1.46-2.49; P < 0.001). There was a significant interaction between Lp(a) and LAP (P interaction <0.001) in relation to MI risk. When stratified by the presence or absence of LAP, Lp(a) was associated with MI in patients with LAP (aHR: 3.03; 95% CI: 1.92-4.76; P < 0.001). Mediation analysis revealed that LAP mediated 73.3% (P < 0.001) for the relationship between Lp(a) and MI. The principal findings remained unchanged in the validation cohort. Elevated Lp(a) augmented the risk of MI during 8 years of follow-up, especially in patients with LAP identified by CCTA. The presence of LAP could reinforce the relationship between Lp(a) and future MI occurrence. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: In recent years, transcatheter aortic valve replacement (TAVR) has emerged as a pivotal treatment for pure native aortic regurgitation (PNAR). Given patients with severe aortic regurgitation (AR) are prone to suffer from pulmonary hypertension (PH), understanding TAVR's efficacy in this context is crucial. This study aims to explore the short-term prognosis of TAVR in PNAR patients with concurrent PH., Methods: Patients with PNAR undergoing TAVR at Zhongshan Hospital, Affiliated with Fudan University, were enrolled between June 2018 to June 2023. They were categorized based on pulmonary artery systolic pressure (PASP) into groups with or without PH. The baseline characteristics, imaging records, and follow-up data were collected., Results: Among the 103 patients recruited, 48 were afflicted with PH. In comparison to PNAR patients without PH, the PH group exhibited higher rates of renal dysfunction (10.4% vs. 0.0%, p = 0.014), increased Society of Thoracic Surgeons scores (6.4 ± 1.9 vs. 4.7 ± 1.6, p < 0.001), and elevated Nterminal fragment of pro-brain natriuretic peptide (NT-proBNP). Transthoracic ultrasound examination revealed that patients with PH displayed lower left ventricular ejection fraction, larger left ventricle dimension, and more frequent moderate to severe tcuspid regurgitation (TR). Following TAVR, both groups experienced significant reductions in PASP, mitral regurgitation (MR) and TR. There were no significant differences in the incidence of postoperative adverse events in patients with or without PH., Conclusions: We found TAVR to be a safe and effective treatment for patients with PNAR and PH, reducing the degree of aortic regurgitation and PH without increasing the risk of postoperative adverse events., Competing Interests: The authors declare no conflict of interest., (Copyright: © 2024 The Author(s). Published by IMR Press.)