Phenotyping Resting and Exertional Right Ventricular Dysfunction Among Patients With Chronic Obstructive Pulmonary Disease

Inclusion Criteria:

* COPD (determined by ratio of forced expiratory volume in 1 second to forced vital capacity \[FEV1/FVC\] \<0.7)
* Age \>= 40 years

Exclusion Criteria:

* Exacerbation of COPD in the 3 months prior to enrollment
* Change in COPD therapy in the 3 weeks prior to enrollment
* Requirement of \>6 LPM supplemental oxygen at rest
* Requirement of \>10 LPM supplemental oxygen with exertion
* Active/uncontrolled cardiovascular disease (e.g. hypertension with blood pressure \>150/100 despite antihypertensives; coronary artery disease with angina; left ventricular ejection fraction ≤40%; arrhythmia; pulmonic, mitral or aortic valvular abnormality greater than mild in severity; tricuspid regurgitation greater than moderate in severity)
* Volume overload (jugular vascular distension or greater than trace peripheral edema)
* World Health Organization Functional Class IV
* Known pulmonary hypertension with mean pulmonary artery pressure \>45 mmHg
* Untreated severe obstructive sleep apnea or obesity hypoventilation syndrome
* Active malignancy (other than skin)
* Medical conditions that limit exercise on an upright stationary bicycle (e.g. severe osteoarthritis, imbalance/gait instability, etc.)
* Pregnancy
* Body mass index \<18 or \>40
* Hematocrit \<25% or \>55%
* For invasive CPET, chronic anticoagulation that is unable to be held for the study visit
* For invasive CPET, forced expiratory volume in 1 second of \<20%