This study plans to learn about heart function among individuals with chronic obstructive pulmonary disease (COPD). In particular, the investigators want to understand the different patterns of right ventricular response during rest and moderate- vs high-intensity exercise. By identifying patterns of right ventricular dysfunction, this study will help identify better treatments for patients with COPD in the future.

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%