Common symptoms include: Shortness of breath. This symptom usually appears suddenly. Trouble catching your breath happens even when resting and gets worse with physical activity. Chest pain. You may feel like you're having a heart attack. The pain is often sharp and felt when you breathe in deeply. However, symptoms of a blood clot waiting to dislodge and travel to the lungs may include leg pain, swelling and warmth. Take those signs just as seriously and seek medical care right away. A pulmonary embolism (PE) is a blood clot that blocks the flow of blood to part of one lung. Many people with this condition have two or more clots in one or both lungs. Symptoms of a pulmonary embolism can be subtle: for example, shortness of breath on exertion or intermittent chest pains. Every year, about 900,000 Americans develop a pulmonary embolism (PE), or a blood clot in the lungs. Learn more about this acute life-threatening problem, including the seven warning signs that should prompt you to seek emergency care. What are the Symptoms of Pulmonary Embolism? The signs and symptoms of pulmonary embolism vary greatly depending on the size of the clot, how much of the lung is involved and whether you have an underlying medical condition. The most common symptoms are: Chest pain that becomes worse when breathing in. The signs and symptoms of a pulmonary embolus are caused by decreased lung function and the inability of the lung to provide adequate oxygen to the rest of the body. Signs and symptoms of pulmonary embolism can include: If you have a wearable device, you may also notice your heart rate go up unexpectedly even when you’re at rest. “Once the blood clot travels to the lungs, the symptoms can be really nonspecific,” Pugliese says. A pulmonary embolism (PE) can strike with no symptoms. But most of the time, your body will let you know something’s wrong. WebMD describes the telltale signs and explains when to call the... It can be life-threatening if not treated quickly. Symptoms of a pulmonary embolism include: You may also have pain, redness and swelling in one of your legs (usually the calf). These are symptoms of a blood clot, also called DVT (deep vein thrombosis). You can call 111 or get help from 111 online. Learn the key warning signs of a pulmonary embolism, from chest pain and breathlessness to subtle clues you might overlook, and when to seek emergency care.