Usefulness of Red Cell Distribution Width as a Prognostic Marker in Pulmonary Hypertension††Conflicts of interest: Dr. Gomberg-Maitland has received research grant support from Actelion Pharmaceuticals Ltd., Allschwil, Switzerland; CoTherix, Inc., South San Francisco, California; Encysive Pharmaceuticals Inc., Houston, Texas; Gilead Sciences Inc., Foster City, California; Eli Lilly/ICOS, Indianapolis, Indiana; Pfizer Inc., New York, New York; and United Therapeutics, Silver Spring, Maryland. Dr. Gomberg-Mai