Serena Williams' Pulmonary Embolism, Hematoma

Tennis star Serena Williams is recovering from a pulmonary embolism and a hematoma resulting from her treatment, according to media reports.
What is a pulmonary embolism? How can something so scary happen to a world-class athlete? Do people fully recover from a pulmonary embolism?
To answer these and other questions, WebMD consulted Shirin Shafazand, MD, MPH, assistant professor of medicine in the division of pulmonary critical care at the University of Miami Miller School of Medicine.
Shafazand has not examined Williams and has not seen her medical records. She commented on publicly available details of Williams' condition and on her extensive experience treating patients with pulmonary embolisms.
-What happened to Serena Williams?
Shortly after winning her fourth Wimbledon title last July, Williams cut her foot on a shard of glass. The severe cut required surgery and 18 stitches. Although she played an exhibition match shortly thereafter, continuing problems with the foot has kept her out of competition since then.
According to a statement from her representative in People magazine, Williams was in New York last week undergoing further treatment for her foot injury. She flew back to Los Angeles and apparently suffered a pulmonary embolism during or shortly after the flight.
On Feb. 28, she "underwent emergency treatment" for a hematoma she suffered as a result of her treatment for pulmonary embolism.
Williams is reported to be recovering.
-What is a pulmonary embolism?
A pulmonary embolism is a blood clot that blocks a major artery feeding the lungs.
These clots usually arise in the leg, usually in a deep vein. Doctors call such a clot a thrombosis. A clot arising in a deep leg vein is called a deep venous thrombosis or DVT. DVTs often arise after a period of inactivity and are particularly common after long airplane flights. A clot originating in a deep leg vein in some cases will break free and travel to the lungs, causing a pulmonary embolism.
Williams may have been relatively inactive because of the foot injury. The risk of DVT is increased with inactivity.
"Her injury could have led to a clot in the leg," Shafazand suggests. "And New York to California is quite a long trip -- and that could increase risk of the slowing down of blood flow in the leg, which could lead to a DVT."
Some people with very small pulmonary embolisms never notice them. But larger clots block blood flow to significant portions of the lungs.
"A large pulmonary embolism cuts blood circulation to the lungs and decreases oxygen levels in the body. A patient can very quickly deteriorate and die," Shafazand says. "And the heart, which is supposed to pump the blood through the arteries, can fail because it cannot stand the pressure buildup from the blockage.
**published in "WEB MD"