RELATED: If You Feel This in Your Legs, Call 911 Immediately. Pulmonary hypertension (PH) is a serious condition that occurs when the arteries that deliver blood from the heart to the lungs narrow, causing high blood pressure. In the event of PH, “overworked and enlarged, the right ventricle gradually becomes weaker and loses its ability to pump enough blood to the lungs,” explains the Cleveland Clinic. Ultimately, this can cause some patients with pulmonary hypertension to develop heart failure, a life-threatening progressive condition in which the heart fails to pump blood as it should. Symptoms of PH include irregular pulse, weakened heartbeat, shortness of breath during exercise, dizziness, and labored breathing while at rest. This lung condition can also present with symptoms that specifically occur in the legs: namely pain, cramping, and swelling. Some people with pulmonary hypertension will notice pain or swelling in their ankles and feet as well. RELATED: This Is Why Your High Blood Pressure Isn’t Responding to Medication. Pulmonary embolism (PE) occurs when one of the pulmonary arteries in your lungs becomes blocked. This usually takes place as the result of a blood clot in the deep veins of the legs, though blood clots can also (albeit less frequently) travel to the lungs from the arms or other body parts.ae0fcc31ae342fd3a1346ebb1f342fcb People with PE often experience chest pain, shortness of breath, or persistent cough. They may also experience lightheadedness, sweating, irregular heartbeat, fever, or clammy skin. Those with deep vein thrombosis (DVT), a direct precursor to pulmonary embolism, may experience swelling, pain, soreness, or swelling in one leg. Some DVT patients also experience skin discoloration, or a feeling of warmth in the affected leg. If you notice that your legs appear blue, purple, or gray in color, it could be a sign of cyanosis, a condition of the heart and lungs which occurs when blood oxygen saturation levels fall below 85 percent. While there are a range of underlying conditions that can cause cyanosis, several of its most common causes are linked to the lungs. These include chronic obstructive pulmonary disease (COPD), pulmonary hypertension, asthma, and pneumonia. For more health news sent directly to your inbox, sign up for our daily newsletter. Pulmonary edema is a potentially life-threatening condition marked by the presence of excess fluid in the air sacs of the lungs. Because fluid pools where air should be, patients with pulmonary edema find it increasingly difficult to breathe. Acute pulmonary edema occurs suddenly, often presenting with shortness of breath, anxiety, wheezing, persistent cough (sometimes producing pink, frothy sputum), rapid heartbeat, or lightheadedness. As a chronic condition, pulmonary edema may include these symptoms and also include weight gain, fatigue, and swelling in the legs and sometimes feet. Speak with you doctor if you notice any abnormal changes in your legs, especially if you have a known condition affecting your lungs. It is especially important to seek medical assistance if you experience pain, swelling, discoloration, or persistent cramping with no known cause. RELATED: If Your Legs Feel Like This, Get Your Heart Checked.