Yes, this condition can be serious. Any time a blood clot forms, it runs the risk of breaking apart and travelling through the blood stream up to the lungs. When this happens, an individual could develop a pulmonary embolism, a condition where a blood clot lodges in an artery in the lungs. Pulmonary embolism is a life-threatening event that can damage the other organs in the body and even lead to death.
Signs of pulmonary embolism include shortness of breath, chest pain, lightheadedness, rapid pulse and coughing up blood. If you are having any of these symptoms, you should call 911 or go to your nearest emergency room.