Knowing the Facts
Basic Facts About Thrombosis:
Q – What is DVT?A – DVT (deep vein thrombosis) is a blood clot in a major vein, usually in the leg.
Q – What is PE?
A – PE (pulmonary embolism) is a blood clot in the lungs.
Q – What is VTE?
A – VTE (Venous thromboembolism) is a disease that includes DVT and PE.
Q – What is the connection between DVT and PE?
A – PE is most often caused by part or all of a recently formed DVT breaking away and traveling to the veins in the lungs.
Q – How frequently do these occur?
A – These occur in hundreds of thousands of people in the United States every year. In the estimation of many doctors, as many as 80% of these are not diagnosed and many of those are never noticed by the patient and have minimal adverse effects.
Q – Who is at risk for DVT and PE?
A – There are many risk factors. The most likely of these is inherited genetic factors. Inactivity, surgery, smoking, cancer, advanced age and use of birth control pills or hormone medications also increase the risks. Approximately 2/3 of clots have no known cause.
Q – What are the symptoms of DVT?
A – DVT frequently show up as a deep pain in the calf, sometimes accompanied by swelling and redness.
Q – What are the symptoms of a PE?
A – PE usually presents itself as unusual shortness of breath following exertion. This is often accompanied by pain in the back or chest in the area of the lungs.
Q – How is DVT diagnosed?
A – The simplest, most common and accurate diagnosis is made with venous ultrasound examination of the legs. The ultrasound test will often show if the flow has been stopped by a blood clot in a vein, which will also show up as an incompressible area in the vein.
Q – How is PE diagnosed?
A – PE can be most accurately diagnosed with a CT scan of the lungs using contrast dye. This will show areas of the lungs where the blood flow is impeded.
Additional Information:
Everyone has experienced the superficial clotting that normally occurs with minor cuts and abrasions. However, most patients are completely unfamiliar with deep vein clots despite the fact that perhaps 5% of the population will experience these at some point in their lives. Frequently clots go undiagnosed for many weeks because their symptoms are similar to so many other diseases, and because the patients themselves don’t suspect this as a potential cause of their discomfort.
Thrombosis is the formation of a blood clot within a blood vessel causing a partial or total blockage and preventing blood from flowing normally through the circulatory system. Partial or complete detachment of the clot from the blood vessel wall permits the clot to travel (embolize) to vital organs, such as the brain, heart, lungs, or leg arteries, within the body. The free-flowing blood clot can lodge within the blood vessels and prevent blood from flowing to these organs. Life threatening conditions can follow, such as stroke, heart attack, pulmonary embolism, limb-threatening gangrene.
Each year, in the United States alone, somewhere between 900,000 to 2,000,000 people will develop blood clots in the lungs or major veins. Annually, more people die from blood clots and the resulting complications than from AIDS, breast cancer, and motor vehicle accidents combined. Fatal pulmonary embolism (PE) – blood clot in the lungs – may be the most common preventable cause of hospital death in the United States.
Deep vein thrombosis or DVT is often considered the "silent disease" reflecting, at least in part, the limited public awareness. The high frequency of vascular thrombosis and the potential of a devastating or fatal outcome make VTE a public health risk. Despite the severity of the disease, the public does not know enough about prevention, treatment, or the potential of the devastating or even possibly fatal outcome of VTE.
Risk factors that contribute to VTE are varied and include:
- Immobilization
- Hypercoagulability
- Vessel wall damage
- Previous history of DVT/PE
- Age
- Surgery
- Cancer
- Heredity (including the Factor V Leiden genetic mutation)
- Pregnancy
- Increased estrogen levels (oral contraception, HRT)
- Obesity
- Smoking
- Crohn’s Disease
- Sickle Cell Disease
- Air Pollution
There is greater public awareness about blood clots within the arteries or arterial thrombosis. Arterial thrombosis within the coronary arteries leads to heart attack, while blockage of the cerebral blood vessels causes stroke. Of note is that venous and arterial thromboses share many of the same risk factors, including cigarette smoking, hypertension, and diabetes.
Stroke and myocardial infarction are major causes of death. It is estimated that every 45 seconds, someone in the United States suffers from a stroke. Annually, approximately 700,000 people experience a new or recurrent stroke; about 500,000 of these are first attacks, and 200,000 are recurrent attacks. The estimated frequency of a heart attack is even greater. Each year approximately 1,2000,000 people living in the United States will suffer from a new or recurrent myocardial infarction. In addition, it is estimated that there are 175,000 silent first heart attacks each year.
Patient Experiences:
"In retrospect, I realize how much my life style contributed to my risk of suffering from a VTE. I was in my early 40’s and was still taking birth control pills. As a professional speaker and author, I was either on my feet for long period of times or sitting in front of a computer. My sitting habits didn’t help either. I was most comfortable sitting on my legs, a position I kept until I could feel my feet fall asleep."
"When I first woke up with a pain in my leg, I assumed it was a pulled or strained muscle and didn't think much about it. As the days progressed, it became more painful, achy, and tender; it became more difficult to walk. The pain felt like it was coming from behind my knee but, as the days passed, it seemed to travel down my leg. In my ignorance, I thought the pain was working itself down and out my leg because it seemed to be improving. All of this lasted for almost two weeks before I finally went to see my doctor late one Friday afternoon. As I discovered later, I was lucky that I finally sought medical attention before I boarded a plane for a long haul flight early scheduled for the following Monday morning! Not only did I have a DVT, but I later learned that I had a Pulmonary Embolism as well."
"I had never thought about it, but I had a family history of blood clots; my father had suffered from a DVT. It didn’t occur to me to bring it up when I gave my medical history prior to my orthopedic surgery. Of course, I guess it didn’t help that when I was younger and an avid skier I was convinced that the using extra tight ski boots, which cut off my circulation, would make me a better skier."
"I was only in my 30’s when I suffered my VTE. It was several weeks after my knee surgery. Up until that point, I was healing normally; I had even returned to work. Suddenly, my leg started to hurt – far worse than it had immediately after my surgery. The excruciating pain was centered just behind my knee. I didn’t think to belabor the point when the doctor reassured me that I was still post-surgery. It was only when I suddenly had difficulty breathing that I knew there was something seriously wrong. Fortunately, my co-workers saw the turn for the worse and rushed me to the hospital."