3 Part Study to Assess Inhaled Nitric Oxide on Functional Pulmonary Imaging in Subj. Pulmonary Hypertension Associated w/ COPD and IPF

Inclusion Criteria: * Subjects must meet all of the following inclusion criteria to be enrolled and eligible to participate in the study: 1. A confirmed diagnosis of COPD by the Global initiative for chronic Obstructive Lung Disease (GOLD) criteria 2. Pulmonary hypertension determined by one of the following within the past 12 months: 1. A right heart catheterization (not obtained within ± 7 days of an exacerbation) with an mPAP ≥ 25 mmHg, or 2. An echocardiogram (not obtained within ± 7 days of an exacerbation) with a TRV ≥ 2.9 m/s or sPAP ≥ 38 mmHg (Note: a subject with an acceptable mPAP ≥ 25 mmHg determined by right heart catheterization will meet this inclusion criteria even with a TRV \< 2.9 m/s) 3. Current or former smokers with at least 10 pack-years of tobacco cigarette smoking before study entry 4. Age ≥ 40 years, ≤ 80 years 5. A post-bronchodilatory FEV1/FVC \< 0.7 and a FEV1 \< 60% predicted (values obtained within 6 months prior to screening can be used unless obtained within ± 7 days of an exacerbation; otherwise, the test must be performed during screening) 6. Receiving LTOT for ≥ 3 months and ≥ 10 hours per day as determined by history 7. Females of childbearing potential must have a negative pre-treatment urine pregnancy test 8. Signed informed consent prior to the initiation of any study mandated procedures or assessments Exclusion Criteria: * Subjects who meet any of the following criteria are not eligible for enrollment: 1. A diagnosis of asthma or other non-COPD respiratory disease, in the opinion of the Investigator 2. Lack of patency of nares upon physical examination 3. Experienced during the last month an exacerbation requiring: 1. start of or increase in systemic oral corticosteroid therapy and/or 2. hospitalization 4. Left ventricular dysfunction as measured by: 1. Screening echocardiographic evidence of left ventricular systolic dysfunction (left ventricular ejection fraction \[LVEF\] \< 40%), or 2. Screening echocardiographic evidence of left ventricular diastolic dysfunction \> moderate (i.e., \> Grade 2), or 3. Any history of pulmonary capillary wedge pressure (PCWP), left atrial pressure (LAP) or left ventricular end diastolic pressure (LVEDP) \> 18 mmHg as measured during cardiac catheterization within the past 6 months unless documented to have resolved by a subsequent cardiac catheterization 5. Renal impairment (i.e., an estimated GFRMDRD \< 60 ml/min/1.73 m2) or history of renal failure using the equation (Levey et al., 2007): estimated GFRMDRD = 175×Scr -1.154×Age-0.203 ×1.212 (if black) ×0.742 (if female) where Scr = Standardized serum creatinine 6. Known allergy to contrast media. 7. Clinically significant valvular heart disease that may contribute to PH, including mild or greater aortic valvular disease (aortic stenosis or regurgitation) and/or moderate or greater mitral valve disease (mitral stenosis or regurgitation), or status post mitral valve replacement 8. Use within 30 days of screening or current use of approved PH medications such as sildenafil or bosentan (use of Cialis® or Viagra® for erectile dysfunction is permitted) 9. Use of investigational drugs or devices within 30 days prior to enrollment into the study 10. Any underlying medical or psychiatric condition that, in the opinion of the Investigator, makes the subject an unsuitable candidate for the study