REGN5381 in Heart Failure Adult Participants With Elevated Pulmonary Capillary Wedge Pressure

This study is researching an experimental drug called REGN5381, further referred to as study drug. The study is focused on adult participants with heart failure that, in the opinion of the study doctor, have a clinical indication for right heart catheterization (RHC). The aim of the study is to evaluate the safety and tolerability of the study drug. The study is looking at several other research questions, including: * What side effects may happen from taking the study drug * How much study drug is in the blood at different times * Whether the body makes antibodies against the study drug (which could make the drug less effective or could lead to side effects)