Young Adults in the Cardiac Intensive Care Unit: Insights from the Critical Care Cardiology Trials Network Registry.

AIMS:While the aging cardiac intensive care unit (CICU) population has been well studied, young adults represent a distinct and underexplored subgroup. We aimed to characterize the demographics, clinical presentations, resource utilization, and outcomes of young adults admitted to contemporary CICUs. METHODS AND RESULTS:We analysed consecutive adult CICU admissions from 2018 to 2023 within the Critical Care Cardiology Trials Network, a multicentre registry of advanced CICUs in North America. Patients aged 18-39 years were classified as 'young adults' and compared with those aged ≥40 years. Among 29 035 CICU admissions, 6.7% (n = 1959) were aged 18-39 years. Young adults were more likely to be female (40.0% vs. 36.4%, P = 0.001) and non-White (55.3% vs. 43.0%, P < 0.001), with fewer traditional cardiovascular risk factors. Heart failure was the leading admission diagnosis among young adults (26.4% vs. 19.5%, P < 0.001). Compared with older adults, young patients were more likely to present with cardiogenic shock (22.4% vs. 18.7%, P < 0.001) and cardiac arrest (12.7% vs. 10.6%, P = 0.003). Utilization of critical care therapies was higher, including mechanical circulatory support (13.1% vs. 11.4%, P = 0.02), with extracorporeal membrane oxygenation comprising a greater share (29.3% vs. 9.9%, P < 0.001). Young admissions had longer CICU stays [2.7 (1.2-5.8) vs. 2.2 (1.1-4.6) days, P < 0.001]. CICU mortality (6.5% vs. 10.5%, P < 0.001) and hospital mortality (9.5% vs. 14.4%, P < 0.001) were significantly lower in the young. CONCLUSION:Young adults admitted to the CICU represent a clinically distinct population, with higher rates of high-acuity presentations and intensive resource use yet lower short-term mortality.