Varshney AS, Berg DD, Katz JN, et al. - Researchers aimed at determining if the United Network for Organ Sharing (UNOS) donor heart allocation system revision in October 2018 has changed the utilization of temporary mechanical circulatory support (MCS) in cardiac intensive care units (CICUs). In addition, they investigated if US transplant centers and US nontransplant centers and Canadian centers differ in temporary MCS use. From the Critical Care Cardiology Trials Network, a multicenter network of tertiary CICUs in North America, 14 centers contributed 2-month snapshots of consecutive medical CICU admissions between September 1, 2017, and September 1, 2018 (prerevision period), and October 1, 2018, and September 1, 2019 (postrevision period) for this cohort study. From these 14 centers in North America, they included 384 patients who were admitted with acute, decompensated, heart failure–related cardiogenic shock. Among these patients, a significant increase in use of temporary mechanical circulatory support was observed in US transplant centers in the year after the UNOS donor heart allocation system revisions. However, this increase was not observed in other cardiac intensive care units and for other forms of cardiogenic shock.