Background: Liver diseases drive the development and progression of atrial fibrillation (AF). The Fibrosis-4 (FIB4) index is a non-invasive scoring method for detecting liver fibrosis, but the prognostic impact of using it for AF patients is still unknown. Herein, we evaluated using the FIB4 index as a risk assessment tool for cardiovascular events and mortality in patients with AF. Methods: We performed a post-hoc analysis of a prospective, observational multicenter study. A total of 3067 patients enrolled in a multicenter Japanese registry were grouped as first tertile (FIB4 index < 1.75, n = 1022), second tertile (1.75 ≤ FIB4 index < 2.51, n = 1022), and third tertile (FIB4 index ≥ 2.51, n = 1023). Results: The third tertile had statistically significant results: older age, lower body mass index, increased heart failure prevalence, and lower clearances of hemoglobin and creatinine (all p < 0.05). During the follow-up period, incidences of major bleeding, cardiovascular events, and all-cause mortality were significantly higher for the third tertile (all p < 0.05). After multivariate adjustment, the third tertile associated independently with cardiovascular events (HR 1.72; 95% CI 1.31–2.25) and all-cause mortality (HR 1.43; 95% CI 1.06–1.95). Adding the FIB4 index to a baseline model with CHA₂DS₂-VASc score improved the prediction of cardiovascular events and all-cause mortality, as shown by the significant increase in the C-statistic (all p < 0.05), net reclassification improvement (all p < 0.001), and integrated discrimination improvement (all p < 0.001). A FIB4 index ≥ 2.51 most strongly associated with cardiovascular events and all-cause mortality in AF patients with high CHADS₂ scores (all p < 0.001). Conclusions: The FIB4 index is independently associated with risks of cardiovascular events and all-cause mortality in AF patients.

Objectives Atrial fibrillation (AF) is a heterogeneous condition. We performed a cluster analysis in a cohort of patients with AF and assessed the prognostic implication of the identified cluster phenotypes. Methods We used two multicentre, prospective, observational registries of AF: the SAKURA AF registry (Real World Survey of Atrial Fibrillation Patients Treated with Warfarin and Non-vitamin K Antagonist Oral Anticoagulants) (n=3055, derivation cohort) and the RAFFINE registry (Registry of Japanese Patients with Atrial Fibrillation Focused on anticoagulant therapy in New Era) (n=3852, validation cohort). Cluster analysis was performed by the K-prototype method with 14 clinical variables. The endpoints were all-cause mortality and composite cardiovascular events. Results The analysis subclassified derivation cohort patients into five clusters. Cluster 1 (n=414, 13.6%) was characterised by younger men with a low prevalence of comorbidities; cluster 2 (n=1003, 32.8%) by a high prevalence of hypertension; cluster 3 (n=517, 16.9%) by older patients without hypertension; cluster 4 (n=652, 21.3%) by the oldest patients, who were mainly female and with a high prevalence of heart failure history; and cluster 5 (n=469, 15.3%) by older patients with high prevalence of diabetes and ischaemic heart disease. During follow-up, the risk of all-cause mortality and composite cardiovascular events increased across clusters (log-rank p<0.001, p<0.001). Similar results were found in the external validation cohort. Conclusions Machine learning-based cluster analysis identified five different phenotypes of AF with unique clinical characteristics and different clinical outcomes. The use of these phenotypes may help identify high-risk patients with AF.

BACKGROUND: Left atrial (LA) dysfunction is common in heart failure (HF) with preserved ejection fraction. However, data on the pathophysiologic impacts of impaired LA functional reserve remained limited. We sought to determine the association of abnormal LA dynamics during exercise with cardiovascular reserve, exercise capacity, and clinical outcomes. METHODS: Patients with HF with preserved ejection fraction (n=231) and controls without HF (n=219) underwent exercise stress echocardiography with simultaneous expired gas analysis. LA function was assessed at rest and during exercise using speckle-tracking echocardiography. RESULTS: Patients with HF with preserved ejection fraction demonstrated less increase in LA reservoir and booster pump strain during exercise than those in controls. The degree of LA dilation was more closely related to exercise LA reservoir strain than to resting LA strain (Meng test, P =0.002). The presence of impaired LA reservoir strain during exercise was associated with poorer biventricular systolic reserve and cardiac output augmentation, more severe right ventricular-pulmonary artery uncoupling, and lower peak oxygen consumption. Patients with a lower exercise LA reservoir strain had a 2.7-fold increased risk of HF events (hazard ratio, 2.66 [95% CI, 1.32–5.38]; P =0.006). Among patients with follow-up echocardiography, initiation of guideline-directed medical therapy or atrial fibrillation ablation showed significant improvements in LA reservoir ( P <0.001 and P =0.022) and booster pump strain ( P =0.011 and 0.028) at rest and during exercise, respectively. CONCLUSIONS: Impaired LA reservoir function during exercise in HF with preserved ejection fraction is associated with biventricular reserve limitations, exercise intolerance, and increased risks of HF events.

Historically, humoral immunity was considered unimportant in anti-tumor immunity, and the differentiation and anti-tumor activity of B cells in breast cancer are poorly understood. However, it was recently discovered that B cells participate in tumor immunity through both antibody production and immunosuppressive mechanisms. We analyzed the expression of B-cell differentiation markers in detail using fluorescence-activated cell sorting to investigate the relationship between B-cell subsets and breast cancer etiology.

Aims: Sodium-glucose co-transporter 2 (SGLT2) inhibitors have shown potential therapeutic benefits in heart failure (HF). However, data on their real-world usage and benefits in acute decompensated heart failure (ADHF) are limited. Methods and results: We conducted a post hoc analysis of real-world data from 1108 patients with ADHF admitted to Nihon University Itabashi Hospital (Tokyo, Japan) between 2018 and 2022. Patients were divided into two groups based on the prescription of SGLT2 inhibitors during hospitalization: an SGLT2 inhibitor group (SGLT2i group) (n = 289) and a non-SGLT2i group (n = 819). The primary endpoints were death and rehospitalization for HF after discharge. The median age was 76 [interquartile range (IQR): 66, 83] years, and 732 patients (66%) were male. Data showed an increasing trend in the prescription of SGLT2 inhibitors since 2021. During a median follow-up period of 366 days (IQR: 116, 614), 458 (41.3%) patients reached the primary endpoint. The Kaplan–Meier analysis showed that the SGLT2i group had a significantly lower rate of composite events than the non-SGLT2i group, both overall (log-rank test, P < 0.001) and in the following left ventricular ejection fraction (LVEF) subgroups: HF with reduced ejection fraction (EF) (n = 413), HF with mildly reduced EF (n = 226), and HF with preserved EF (n = 466) (log-rank test; P = 0.044, P = 0.013, and P = 0.001, respectively). Furthermore, patients starting SGLT2 inhibitors during hospitalization had a significantly lower rate of composite events than those not using SGLT2 inhibitors (log-rank test, P < 0.001). This association was also significant in the LVEF subgroups (P = 0.005, P = 0.032, and P = 0.004, respectively). Conclusions: The prescription and initiation of SGLT2 inhibitors during hospitalization are associated with improved post-discharge outcomes in patients with ADHF, irrespective of LVEF.

Aims Malnutrition is common and associated with worse clinical outcomes in patients with heart failure (HF). The Controlling Nutritional Status (CONUT) score is an integrated index for evaluating diverse aspects of the complex mechanism of malnutrition. However, the relationship between the severity of malnutrition assessed by the CONUT score and clinical outcomes of HF patients receiving cardiac resynchronisation therapy (CRT) has not been fully clarified. Methods Clinical records of 263 patients who underwent pacemaker or defibrillator implantation for CRT between March 2003 and October 2020 were retrospectively evaluated. The CONUT score was calculated from laboratory data obtained before CRT device implantation. Patients were divided into three groups: normal nutrition (CONUT scores 0–1, n=58), mild malnutrition (CONUT scores 2–4, n=132) and moderate or severe malnutrition (CONUT scores 5–12, n=73). The primary endpoint was all-cause mortality. Results The moderate or severe malnutrition group had a lower body mass index, more advanced New York Heart Association functional class, higher Clinical Frailty Scale score, lower levels of haemoglobin and higher levels of N-terminal probrain natriuretic peptide (all p<0.05). In the moderate or severe malnutrition group, the CRT response rate was significantly lower than for the other two groups (p=0.001). During a median follow-up period of 31 (10–67) months, 103 (39.1%) patients died. Kaplan-Meier analysis revealed that the moderate or severe malnutrition group had a significantly higher mortality rate (log-rank p<0.001). A higher CONUT score and CONUT score ≥5 remained significantly associated with all-cause mortality after adjusting for previously reported clinically relevant factors and the conventional risk score (VALID-CRT risk score) (all p<0.05). Conclusions A higher CONUT score before CRT device implantation was strongly associated with HF severity, frailty, lower CRT response rate and subsequent long-term all-cause mortality.