High blood pressure in your lungs (pulmonary hypertension): Unlike systemic high blood pressure, this condition affects only the arteries in your lungs. It begins when the smallest arteries and capillaries are compressed by scar tissue, causing increased resistance to blood flow in your lungs. This in turn raises pressure within the pulmonary arteries and the lower right heart chamber (right ventricle). Some forms of pulmonary hypertension are serious illnesses that become progressively worse and are sometimes fatal.
Right-sided heart failure (cor pulmonale): This serious condition occurs when your heart's lower right chamber (ventricle) has to pump harder than usual to move blood through partially blocked pulmonary arteries.
Respiratory failure: This is often the last stage of chronic lung disease. It occurs when blood oxygen levels fall dangerously low.
Lung cancer: Long-standing pulmonary fibrosis also increases your risk of developing lung cancer.
Lung complications: As pulmonary fibrosis progresses, it may lead to complications such as blood clots in the lungs, a collapsed lung or lung infections.
Courtesy: Mayo Clinic