 This study examined the causes, clinical burden, and outcomes of patients admitted to the intensive care unit, ICU, with pulmonary arterial hypertension, PAH. It found that right heart failure, RHF, was the most common cause for ICU admission, followed by infections and arrhythmias. Patients with connective tissue disease associated PAH had lower one-year survival than those with idiopathic PAH. Additionally, certain risk factors such as low sodium levels, elevated pro-B type natriuretic peptid, pro-BNP, hyperbillirubinemia, hyperlactemia, need for vasopressors, burnotropes, mechanical ventilation, renal replacement therapy, and connective tissue disease associated PAH were associated with higher mortality rates. This article was authored by Mario Naronjo, Valentina McEwio, Hussain Hassan, and others.