On average, patients with Pulmonary hypertension are not diagnosed until the pulmonary vascular bed is significantly damaged, resulting in shortness of breath. A series of diagnostic tests are used to confirm diagnosis, determine etiology and clinical classification, evaluate functional ability, and assess hemodynamic status. These tests can provide valuable information to the clinician and facilitate diagnosis. As stated in the introduction, Pulmonary hypertension is linked to several comorbidities, making it important for the NP to develop a list of possible differential diagnoses. Possible differential diagnoses include sleep apnea, cor pulmonale, pulmonary embolism, hypothyroidism, mixed connective tissue disease (scleroderma and systemic lupus erythematosus), and portal hypertension.