During sea level rise, salt marshes transgress inland invading low-lying forests, agricultural fields, and suburban areas. This transgression is a complex process regulated by infrequent storms that flood upland ecosystems increasing soil salinity. As a result upland vegetation is replaced by halophyte marsh plants. Here we present a review of the main processes and feedbacks regulating the transition from upland ecosystems to salt marshes. The goal is to provide a process-based framework that enables the development of quantitative models for the dynamics of the marsh-upland boundary. Particular emphasis is given to the concept of ecological ratchet, combining the press disturbance of sea level rise with the pulse disturbance of storms.

The retreat of coastal forests as sea level rises is well documented; however, the mechanisms which control this retreat vary with the physical and biological setting of the interface between tidal marsh and forest. Tidal flooding and saltwater intrusion as well as flooding and wind associated with storms can kill trees. Even if these processes do not kill stands, they may halt regeneration because seedlings are more sensitive to stress. We present a case study of a coastal pine forest on the Delmarva Peninsula, United States. This forest contains a persistent but nonregenerating zone of mature trees, the size of which is related to the sea level rise experienced since forest establishment. The transgression of coastal forest and shrub or marsh ecosystems is an ecological ratchet: sea-level rise pushes the regeneration boundary further into the forest while extreme events move the persistence boundary up to the regeneration boundary.

The Mid‐Atlantic coastal forests in Virginia are stressed by episodic disturbance from hurricanes and nor'easters. Using annual tree ring data, we adopt a dendroclimatic and statistical modeling approach to understand the response and resilience of a coastal pine forest to extreme storm events, over the past few decades. Results indicate that radial growth of trees in the study area is influenced by age, regional climate trends, and individual tree effects but dominated periodically by growth disturbance due to storms. We evaluated seven local extreme storm events to understand the effect of nor'easters and hurricanes on radial growth. A general decline in radial growth was observed in the year of the extreme storm and 3 years following it, after which the radial growth started recovering. The decline in radial growth showed a statistically significant correlation with the magnitude of the extreme storm (storm surge height and wind speed). This study contributes to understanding declining tree growth response and resilience of coastal forests to past disturbances. Given the potential increase in hurricanes and storm surge severity in the region, this can help predict vegetation response patterns to similar disturbances in the future.

Background Omecamtiv mecarbil (OM) is a selective cardiac myosin activator that promotes contractility in patients with Heart Failure with Reduced Ejection Fraction (HFrEF). We aimed to study the clinical outcomes of OM in this population. Methods PubMed, Cochrane CENTRAL Registry of Controlled Trials, and ClinicalTrials.gov were searched for randomized controlled trials (RCTs) that compared OM with placebo for the management of HFrEF. Efficacy and safety data were summarized with odds ratios (OR) and a 95% confidence interval (CI) using a fixed-effect model predicting low heterogeneity between studies. Results Four RCTs were included, totalizing 9,364 patients, 4,779 treated with OM and 4,585 with placebo. Mean age ranged from 63–66 years, 15–22% female, ejection fraction 26–29%, ischemic etiology 53–66%. Length of follow up ranged from 1 to 21 months. There was no difference in the outcomes all cause death (OR 0.99, 95% CI 0.9–1.1, p=0.91), cardiovascular death (OR 1.01, 95% CI 0.91–1.12, p=0.87) and heart failure events or hospitalizations (OR 0.96, 95% CI 0.87–1.05, p=0.35), Figure. Conclusion In a meta-analysis of 4 RCTs, OM showed no difference compared with placebo in the risk of all-cause death, cardiovascular death, or heart failure events among patients with HFrEF. Funding Acknowledgement Type of funding sources: None.

Background Atrial fibrillation (AF) in patients with hypertrophic cardiomyopathy (HCM) is associated with high thromboembolic risk, morbidity, and mortality. Purpose We aimed to study the role of cardiac implantable devices (CID) for AF diagnosis in patients with HCM without prior AF history. Methods A comprehensive systematic review and meta-analysis was conducted using Pubmed, Embase, and ClinicalTrials.gov through November 2021 for studies reporting incidence of new-onset AF detected by CID including implantable cardioverter defibrillators, pacemakers, cardiac resynchronization therapy, and loop recorder devices in HCM patients. We used a Freeman-Tukey transformation to calculate the weighted summary proportion of the incidence of AF and stroke and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated using a random-effects model. Results Eight cohort studies were included, totalizing 910 patients with HCM and CID without baseline AF. Mean age was 54 years and 21% were female. Mean left ventricular wall thickness was 22.6 mm. Mean follow-up was 3.1 years. New-onset AF was detected in 27.6% (95% CI 18.7–37.5) of patients (Figure A) and 84% of the episodes were subclinical. Stroke occurred in 4.7% (95% CI 1.8–9.0) of patients without baseline AF (Figure B). There was no significant difference in the unadjusted risk of stroke between patients with newly diagnosed AF vs no AF detected at the end of follow-up (9.4% vs 4.7%, OR 1.93, 95% CI 0.83–4.48, p=0.13). Conclusion There is a high incidence of subclinical new-onset AF in patients with HCM, supporting the use of CID for early detection of AF in this population. Funding Acknowledgement Type of funding sources: None.