COPD can lead to pulmonary hypertension. This is a condition in which blood pressure in the arteries that carry blood from the heart to the lungs is elevated.“People with COPD often have low levels of oxygen in the blood, which is known as hypoxia,” says Dr. Pistenmaa. “Over time, hypoxia can cause the vessels [between the heart and lungs and within the lungs] to constrict, which increases the pressure in those arteries.” Eventually, even mildly low oxygen levels can lead to pulmonary hypertension, she adds.Emphysema, which causes damage to the air sacs in the lungs, can also destroy small blood vessels in the lungs. This further increases pressure in other vessels.With pulmonary hypertension, the right side of your heart has to work harder to move blood through the lungs. This can cause the right side of the heart to enlarge and ultimately fail, a condition called right-sided heart failure, or cor pulmonale.[4]Early signs of pulmonary hypertension include shortness of breath, light-headedness during physical activity, or palpitations (fast heart rate). Over time, symptoms may occur with lighter activity or even while at rest.[4]As pulmonary hypertension progresses, other symptoms include:Ankle and leg swellingBluish color of the lips or skinChest pain or pressure, most often in the front of the chestDizziness or fainting spellsFatigueIncreased abdomen sizeWeaknessMild pulmonary hypertension typically doesn’t require any treatments other than management of the underlying COPD, says Pistenmaa. That said, if your blood oxygen levels are low at rest or while exercising, supplemental oxygen may help reduce the stress on the heart.If you develop moderate to severe pulmonary hypertension, you may need to take blood thinners and use oxygen therapy at home. In rare cases, people with severe pulmonary hypertension may need to undergo a lung or heart-lung transplant.[5]