Hypertrophic cardiomyopathy (HCM) is the most common monogenic heart disease, with an estimated prevalence of 1:600 in the general population, and is associated with significant morbidity. HCM is characterized by left ventricular hypertrophy and interventricular septal thickening due to sarcomere protein gene mutations. The recent emergence of cardiac myosin inhibitors (CMIs), specifically mavacamten and aficamten, has introduced a paradigm shift in HCM management by directly targeting the hypercontractile state of the disease. This review comprehensively discusses the molecular mechanisms of mavacamten and aficamten, highlighting their biochemical similarities and differences from available data. It evaluates their reported efficacy in completed clinical trials, such as reducing left ventricular outflow tract (LVOT) obstruction, improving functional capacity, and enhancing quality of life in HCM. It further provides insight and updates to ongoing trials of both CMIs. Finally, it compares and elaborates on the safety profiles of mavacamten and aficamten, discussing their favorable safety profiles shown in completed studies. In current clinical practice, only mavacamten is approved for use, and clinical insights concerning both CMIs are limited, but encouraging. In summary, cardiac myosin inhibitors are a promising class of disease-modifying drugs for HCM with proven short-term safety and efficacy, but limited data are available to fully determine their long-term effects and efficacy in diverse patient populations. Ongoing research is necessary to further explore and define their role in HCM management.

Background: Out-of-hospital cardiac arrest (OHCA) remains a major public health challenge across Europe. While prehospital emergency medical services (EMS) vary widely, the degree to which regional infrastructure, dispatch guidance, and community responder frameworks influence clinical outcomes when mapped against standardized reporting templates remains insufficiently synthe-sized. This scoping review evaluates European OHCA evidence across standardized Utstein re-porting domains to analyze prehospital system factors, responder interventions, and clinical out-comes. Methods: Following PRISMA-ScR guidelines and Joanna Briggs Institute (JBI) methodology, a systematic literature search was performed across PubMed, Scopus, and Web of Science (January 2021–March 2026). From 8,882 records identified, 2,126 full-text articles were evaluated using a Population, Exposure, Outcome (PEO) framework. Data were synthesized across four core Utstein domains. Results: Forty three primary studies (N = 43) were included. System Factors demonstrated that prolonged ambulance response intervals severely diminish survival, particularly in sparsely populated rural sectors. Dispatch Protocols highlighted that rapid dispatcher recognition signifi-cantly increases telephone CPR instructions and community resource activation. Under bystander a prominent gap was identified between public AED availability and actual lay bystander deployment (< 5%). Dispatched Volunteer Community Responders (VCR) and First Responders (FR) achieved median arrival time-gains of 4–5 minutes; however, survival benefits were descriptively observed primarily when early arrival facilitated ultra-early defibrillation or high-quality CPR. Clinical Out-comes confirmed that 30-day survival and favorable neurological recovery (CPC 1–2) remain highly variable, heavily constrained by reporting heterogeneity. Conclusions: Strengthening early links in the chain of survival—specifically dispatcher recognition, app-alerted volunteer dispatch, and public defibrillation—is consistently associated with improved clinical survival. Universal adoption of the updated Utstein 2024 reporting template is essential to eliminate reporting heterogeneity and enable meaningful cross-system benchmarks across Europe.