Immune Mechanisms of Plaque Instability.

Inflammation crucially drives atherosclerosis from disease initiation to the emergence of clinical complications. Targeting pivotal inflammatory pathways without compromising the host defense could compliment therapy with lipid-lowering agents, anti-hypertensive treatment, and lifestyle interventions to address the substantial residual cardiovascular risk that remains beyond classical risk factor control. Detailed understanding of the intricate immune mechanisms that propel plaque instability and disruption is indispensable for the development of novel therapeutic concepts. In this review, we provide an overview on the role of key immune cells in plaque inception and progression, and discuss recently identified maladaptive immune phenomena that contribute to plaque destabilization, including epigenetically programmed trained immunity in myeloid cells, pathogenic conversion of autoreactive regulatory T-cells and expansion of altered leukocytes due to clonal hematopoiesis. From a more global perspective, the article discusses how systemic crises such as acute mental stress or infection abruptly raise plaque vulnerability and summarizes recent advances in understanding the increased cardiovascular risk associated with COVID-19 disease. Stepping outside the box, we highlight the role of gut dysbiosis in atherosclerosis progression and plaque vulnerability. The emerging differential role of the immune system in plaque rupture and plaque erosion as well as the limitations of animal models in studying plaque disruption are reviewed.

Impact of oral anticoagulation on clinical outcomes of COVID-19: a nationwide cohort study of hospitalized patients in Germany.

OBJECTIVES: The aim of this study was to investigate the impact of concomitant long-term medication-with a focus on ACE inhibitors and oral anticoagulation-on clinical outcomes in patients hospitalized with coronavirus disease 2019. METHODS: This is a retrospective cohort study using claims data of the biggest German health insurance company AOK, covering 26.9 million people all over Germany. In particular, patient-related characteristics and co-medication were evaluated. A multivariable logistic regression model was adopted to identify independent predictors for the primary outcome measure of all-cause mortality or need for invasive or non-invasive ventilation or extracorporeal membrane oxygenation. RESULTS: 6637 patients in 853 German hospitals were included. The primary outcome occurred in 1826 patients (27.5%). 1372 patients (20.7%) died, 886 patients (13.3%) needed respiratory support, and 53 patients (0.8%) received extracorporeal membrane oxygenation. 34 of these patients survived (64.2%). The multivariable model demonstrated that pre-existing oral anticoagulation therapy with either vitamin-K antagonists OR 0.57 (95% CI 0.40-0.83, p = 0.003) or direct oral anticoagulants OR 0.71 (95% CI 0.56-0.91, p = 0.007)-but not with antiplatelet therapy alone OR 1.10 (95% CI 0.88-1.23, p = 0.66)-was associated with a lower event rate. This finding was confirmed in a propensity match analysis. CONCLUSIONS: In a multivariable analysis, a therapy with both direct oral anticoagulants or vitamin-K antagonists-but not with antiplatelet therapy-was associated with improved clinical outcomes. ACE inhibitors did not impact outcomes. Prospective randomized trials are needed to verify this hypothesis.