This is due to the right ventricular stress and ischemia that can occur in PE. Other symptoms are syncope and hemoptysis. DVT is a common cause. Thus, symptoms including leg pain, redness, and swelling can be present. The likelihood of pulmonary embolism can be evaluated through various criteria. The Wells score is often calculated. It gives points based on these symptoms and patient risk factors. Causes
Causes include any obstruction of blood flow to and from the heart. There are multiple, including pulmonary embolism, cardiac tamponade, and tension pneumothorax. Other causes include abdominal compartment syndrome, severe aortic valve stenosis, and disorders of the aorta. Constrictive pericarditis is a rare cause. Masses can grow to press on major blood vessels causing shock. Tension pneumothorax
A pneumothorax occurs when air collects in the pleural space around the lungs. Normally, this space has negative pressure to allow the lung to fill. Pressure increases as more air enters this space. The lung collapses, impairing normal breathing. Surrounding structures may also shift. When severe enough to cause these shifts and hypotension, it is called a tension pneumothorax. This is life-threatening. The veins supplying the heart are compressed. Thus, venous return is decreased. With the heart unable to fill, cardiac output drops. Hypotension and shock ensue. If not rapidly treated, it can lead to cardiac arrest and death. Pulmonary embolism
A pulmonary embolism (PE) is an obstruction of the pulmonary arteries. Deaths from PE have been estimated at ~100,000 per year in the United States. However, this may be higher in recent years.
With proper medical attention, infections can usually be successfully treated without long-term visual loss. In non-humans
Feline eosinophilic keratitis — affecting cats and horses; possibly initiated by feline herpesvirus 1 or other viral infection. See also
Chronic superficial keratitis, or pannus, for the disease in dogs
Thygesons superficial punctate keratopathy
Keratoendotheliitis fugax hereditaria

References
External links

Facts About the Cornea and Corneal Disease The National Eye Institute (NEI)
Filimentary keratitis