Hantavirus cardiopulmonary syndrome (HCPS) is caused by infection with multiple types of hantaviruses throughout the Americas. All strains induce a pulmonary capillary leak syndrome with cardiogenic shock in severe cases, and almost all strains have an overall mortality rate of 35%. Some strains in South America are commonly associated with either mild disease without pulmonary edema or severe disease with pulmonary hemorrhage. Early recognition during the thrombocytopenic prodrome phase and transport to intensive care improve survival, due to very rapid progression of respiratory failure and shock in some patients. Limited fluid replacement, early inotropic therapy, and mechanical ventilation also improve survival. Extracorporeal membrane oxygenation (ECMO) has been life saving for patients with refractory shock. Ribavirin does not appear to reduce mortality, but hyperimmune serum offers a promising future therapy because survival is correlated with higher neutralizing antibody titers at admission.