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Transgenic expression of Cre recombinase driven by a specific promoter is normally used to conditionally knockout a gene in a tissue- or cell-type-specific manner. In αMHC-Cre transgenic mouse model, expression of Cre recombinase is controlled by the myocardial-specific α-myosin heavy chain (αMHC) promoter, which is commonly used to edit myocardial-specific genes. Toxic effects of Cre expression have been reported, including intro-chromosome rearrangements, micronuclei formation and other forms of DNA damage, and cardiomyopathy was observed in cardiac-specific Cre transgenic mice. However, mechanisms associated with Cardiotoxicity of Cre remain poorly understood. In our study, our data unveiled that αMHC-Cre mice developed arrhythmias and died after six months progressively, and none of them survived more than one year. Histopathological examination showed that αMHC-Cre mice had aberrant proliferation of tumor-like tissue in the atrial chamber extended from and vacuolation of ventricular myocytes. Furthermore, the αMHC-Cre mice developed severe cardiac interstitial and perivascular fibrosis, accompanied by significant increase of expression levels of MMP-2 and MMP-9 in the cardiac atrium and ventricular. Moreover, cardiac-specific expression of Cre led to disintegration of the intercalated disc, along with altered proteins expression of the disc and calcium-handling abnormality. Comprehensively, we identified that the ferroptosis signaling pathway is involved in heart failure caused by cardiac-specific expression of Cre, on which oxidative stress results in cytoplasmic vacuole accumulation of lipid peroxidation on the myocardial cell membrane. Taken together, these results revealed that cardiac-specific expression of Cre recombinase can lead to atrial mesenchymal tumor-like growth in the mice, which causes cardiac dysfunction, including cardiac fibrosis, reduction of the intercalated disc and cardiomyocytes ferroptosis at the age older than six months in mice. Our study suggests that αMHC-Cre mouse models are effective in young mice, but not in old mice. Researchers need to be particularly careful when using αMHC-Cre mouse model to interpret those phenotypic impacts of gene responses. As the Cre-associated cardiac pathology matched mostly to that of the patients, the model could also be employed for investigating age-related cardiac dysfunction. [ABSTRACT FROM AUTHOR]

Background: Liver transplantation (LT), resection (LR), and ablation (LA) are three curative‐intent treatment options for patients with early hepatocellular carcinoma (HCC). We aimed to develop a prognostic calculator to compare the long‐term outcomes following each of these therapies. Methods: A total of 976 patients with HCC within the Milan criteria who underwent LT, LR, and LA between 2009 and 2019 from four institutions were evaluated. Multistate competing risks prediction models for recurrence‐free survival (RFS), recurrence within the Milan criteria (RWM), and HCC‐specific survival (HSS) were derived to develop a prognostic calculator. Results: During a median follow‐up of 51 months, 420 (43%) patients developed recurrence. In the multivariate analysis, larger tumor size, multinodularity, older age, male, higher alpha‐fetoprotein (AFP), higher albumin‐bilirubin (ALBI) grade, and the presence of portal hypertension were significantly associated with higher recurrence and decreased survival rates. The RFS and HSS were both significantly higher among patients treated by LT than by LR or LA and significantly higher between patients treated by LR than by LA (all p < 0.001). For multinodular HCC ≤3 cm, although LT had better RFS and HSS than LR or LA, LA was noninferior to LR. An online prognostic calculator was then developed based on the preoperative clinical factors that were independently associated with outcomes to evaluate RFS, RWM, and HSS at different time intervals for all three treatment options. Conclusions: Although LT resulted in the best recurrence and survival outcomes, LR and LA also offered durable long‐term alternatives. This prognostic calculator is a useful tool for clinicians to guide an informed and personalized discussion with patients based on their tumor biology and liver function. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) is underdiagnosed and especially undertreated in China. We aimed to investigate the prevalence of unknown and untreated AF in community residents (≥65 years old) and to determine whether an education intervention could improve oral anticoagulant (OAC) prescription. Methods and findings: We performed a single–time point screening for AF with a handheld single-lead electrocardiography (ECG) in Chinese residents (≥65 years old) in 5 community health centers in Shanghai from April to September 2017. Disease education and advice on referral to specialist clinics for OAC treatment were provided to all patients with actionable AF (newly detected or undertreated known AF) at the time of screening, and education was reinforced at 1 month. Follow-up occurred at 12 months. In total, 4,531 participants were screened (response rate 94.7%, mean age 71.6 ± 6.3 years, 44% male). Overall AF prevalence was 4.0% (known AF 3.5% [n = 161], new AF 0.5% [n = 22]). The 183 patients with AF were older (p < 0.001), taller (p = 0.02), and more likely to be male (p = 0.01), and they had a higher prevalence of cardiovascular disease than those without AF (p < 0.001). In total, 85% (155/183) of patients were recommended for OAC treatment by the established guidelines (CHA2DS2-VASc ≥ 2 for men; ≥ 3 for women). OAC prescription rate for known AF was 20% (28/138), and actionable AF constituted 2.8% of all those screened. At the 12-month follow-up in 103 patients (81% complete), despite disease education and advice on specialist referral, only 17 attended specialist clinics, and 4 were prescribed OAC. Of those not attending specialist clinics, 71 chose instead to attend community health centers or secondary hospital clinics, with none prescribed OAC, and 15 had no review. Of the 17 patients with new AF and a class 1 recommendation for OAC, only 3 attended a specialist clinic, and none were prescribed OAC. Of the 28 AF patients taking OAC at baseline, OAC was no longer taken in 4. Ischemic stroke (n = 2) or death (n = 3) occurred in 5/126 (4%), with none receiving OAC. As screening was performed at a single time point, some paroxysmal AF cases may have been missed; thus, the rate of new AF may be underestimated. Conclusions: We demonstrated a noticeable gap in AF detection and treatment in community-based elderly Chinese: actionable AF constituted a high proportion of those screened. Disease education and advice on specialist referral are insufficient to close the gap. Before more frequent or intensive screening for unknown AF could be recommended in China, greater efforts must be made to increase appropriate OAC therapy in known AF to prevent AF-related stroke. Ji-Guang Wang and colleagues highlight the gap between AF screening and treatment in Chinese residents over 65 years of age. Author summary: Why was this study done?: Atrial fibrillation (AF) is a common heart rhythm problem that often has no symptoms, so it is often underdiagnosed. People with AF can have a very high stroke risk, which is highly preventable with appropriate oral anticoagulant (OAC) medications. Neither the prevalence of unknown and untreated AF in the Chinese community nor whether patient education in the community health center has the potential to improve OAC prescription are known. What did the researchers do and find?: We screened for AF in residents aged ≥65 years in community health centers in Shanghai and provided disease education and advice on referral to specialist clinics for OAC treatment to people with newly detected or undertreated known AF. We demonstrated a noticeable gap in AF detection and treatment: 2.8% of those screened had unknown or untreated AF. At 12 months, only 17/103 people with newly detected or undertreated known AF attended specialist clinics, and only 4/17 had commenced OAC therapy. What do these findings mean?: We highlight a serious public health issue in China with underdiagnosis and undertreatment of AF in the community that requires a whole-of-system approach. To prevent AF-related stroke in China, greater efforts must be made to increase appropriate OAC therapy in people with AF. [ABSTRACT FROM AUTHOR]

Objective To evaluate the feasibility and effect of three-points ablation approach in in treatment of typical atrial flutter guided by CARTO. Methods Twenty-six patients with typical atrial flutter diagnosed by ECG and electrophysiological study (EPS) were enrolled in this study. Activation sequence mapping and linear ablation were performed in 11 patients (conventional group). Three-points guided linear ablation with CARTO system was performed in another 15 patients (three-points group) . Results There was no significant difference in the success rate between the two groups. Both the procedure and fluoroscopic time in three-points group were significantly shorter than that in conventional group [(72.66 ± 29.82) vs (102.52 ± 32.61) min; (4.26 ± 2.76) vs (7.32 ±3.16) min] . Conclusions The three-points ablations approach is as safe and effective as conventional ablation approach in treatment of typical atrial flutter; however, the former can significantly shorten the procedure time and fluoroscopy time. [ABSTRACT FROM AUTHOR]