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Coral diseases contribute to the worldwide loss of coral reefs, with the Black Band Disease (BBD) being a prominent example. BBD is an infectious condition with lesions with a pigmented mat composed of cyanobacteria, sulphate-reducing, sulphide-oxidizing, and heterotrophic bacteria. We compared the heterotrophic bacterial communities of healthy and BBD-affected colonies of the Caribbean coral Orbicella faveolata using culture-dependent and -independent techniques. Twenty and 23 bacterial isolates were identified from healthy and diseased tissues, respectively, which differed in their capacities to metabolize carbohydrates and citrate, either anaerobically or aerobically. They also differed in their quorum-sensing (QS) activity, as QS signaling molecules were found exclusively, and QS-inhibition was found primarily, in isolates from diseased tissues. Screening of bacterial diversity by 16SrDNA metabarcoding showed that members of the bacterial genera Muricauda and Maritimimonas were dominant in healthy tissues whereas members of the cyanobacterial genus Roseofilum were dominant in diseased tissues. These results suggest that bacterial dysbiosis can be linked with altered bacterial communication, likely leading to diachrony and imbalance that may participate in the progression of BBD. Investigating physiological traits and QS-based communication offers insights into the onset and progression of coral infections, paving the way for novel strategies to mitigate their impact., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Background: Age is a major risk factor for development of atrial fibrillation (AF) and associated with increased recurrence rates in the setting of rhythm control. Current data tend to support catheter ablation in elderly patients, but uncertainties exist regarding efficacy and safety of ablation in elderly patients., Methods: This was a prospective single-centre observational study with propensity score matching (PSM) to investigate the influence of age on efficacy and safety of cryoballoon ablation (CBA) stratified by age (< 75 years vs ≥ 75 years) and AF phenotype (paroxysmal vs persistent). Primary efficacy endpoint was recurrence of atrial arrhythmia after a 90-day blanking period. Safety endpoints were death, stroke, or procedure-associated complications., Results: Consecutive patients (n = 953) underwent CBA for first-time AF ablation. Median follow-up was 18 months. By means of PSM, 268 matches were formed. At 1 year, primary efficacy endpoint occurred in 22.4% of young vs 33.2% of elderly patients, including both AF phenotypes (hazard ratio [HR], 0.65; 95% confidence interval [CI], 0.47-0.90; P = 0.01). AF relapse occurred in 19.7% of young vs 28.5% of elderly patients with paroxysmal (HR, 0.63; 95% CI, 0.40-0.99; P = 0.046) compared with 25.9% (30 of 116, young) vs 38.8% (45 of 116, elderly) patients with persistent AF (HR, 0.62; 95% CI, 0.39-0.97; P = 0.038). No difference was observed regarding the incidence of safety endpoints between young and elderly patients (P = 0.38)., Conclusions: CBA is associated with higher recurrence rates in elderly (≥ 75 years) than in younger patients, with highest recurrence rates in elderly patients with persistent AF., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Heart failure with reduced ejection fraction is associated with potentially deleterious imbalance of the cardiac autonomic nervous system. Sacubitril/valsartan (angiotensin receptor-neprilysin inhibitor [ARNI]) reduces cardiovascular mortality and hospitalization for heart failure with reduced ejection fraction. Whether ARNI affects the cardiac autonomic nervous system has not been studied., Methods and Results: This investigator-initiated, prospective, single-center cohort study compared heart rate (HR) variability, HR, deceleration capacity, and periodic repolarization dynamics as noninvasive measures of the cardiac autonomic nervous system before and after initiation of ARNI therapy. Patients underwent standardized 12-lead Holter-ECG, echocardiography and laboratory testing before and 3 months after start of therapy. End points were changes in HR variability (SD of normal-to-normal intervals, mean square of differences between consecutive R-R intervals), HR, deceleration capacity, and periodic repolarization dynamics as well as ventricular function and NT-proBNP (N-terminal pro-B-type natriuretic peptide). Of 63 patients with heart failure with reduced ejection fraction enrolled, 48 (76.2%) patients were still on ARNI at follow-up. SD of normal-to-normal intervals increased from 25 to 36 milliseconds ( P <0.001), mean square of differences between consecutive R-R intervals increased from 12 to 19 milliseconds ( P <0.001), HR decreased from 73±9 bpm to 67±4 bpm, ( P <0.001), and deceleration capacity increased from 2.1 to 4.4 milliseconds ( P <0.001). A trend for periodic repolarization dynamics reduction was observed (5.6 deg 2 versus 4.7 deg 2 , P =0.09). Autonomic changes were accompanied by increased left ventricular ejection fraction (29±6% versus 40±8%, P <0.001) and reduced NT-proBNP (3548 versus 685 ng/L, P <0.001). Correlation analysis showed a significant relationship between volume-unloading (as evidenced by NT-proBNP reduction) and autonomic improvement., Conclusions: Three months of ARNI therapy resulted in a significant increase in cardiac parasympathetic tone. The improvement in autonomic properties may be mediated by "volume unloading" and likely contributes to the beneficial effects of ARNI in heart failure with reduced ejection fraction., Registration: URL: https://www.clinicaltrials.gov; Unique Identifier: NCT04587947.