Your Health A-Z



Venous thromboembolism is a serious and often overlooked condition. But many deaths and disabilities can be prevented through greater awareness of its causes, risk factors, signs and symptoms, says Professor Barry Jacobson, haematologist and director of the Thrombosis and Haemostasis Research Unit at Wits University Health Consortium.

What is venous thromboembolism?
Generally referred to as blood clots, venous thromboembolism (VTE) includes deep-vein thrombosis (a blood clot formed in the deep veins of the leg or pelvis) and pulmonary embolism (when such a blood clot lands in the lungs). ‘Blood clots in the veins cause stasis or lack of blood flow, damaging the lining of the blood vessels and bringing about changes in the consistency of blood,’ says Prof Jacobson. ‘A deep-vein thrombosis in any vein of the leg or pelvis can break away, travel through the heart and into the lung, causing a blockage that could be fatal.’

What are the risk factors?
‘Patients are at risk during long periods of immobility, for example after undergoing surgery. It’s also a risk in the presence of inflammatory conditions such as pneumonia or influenza,’ Prof Jacobson says. Blood clots in the legs and lungs are very common and occur in about one in every 1 000 adults. These rates increase sharply after the age of 45. Oestrogen-based medications such as oral contraceptives or hormone-replacement therapy also increase one’s risk, as does a family history of the condition, obesity, and pregnancy or recent delivery (deep-vein thrombosis and subsequent pulmonary embolism is the leading cause of maternal death).

Few people know how dangerous VTE could be. Are figures available for its prevalence in South Africa?
‘There is much more awareness of the negative health outcomes of breast cancer, prostate cancer, car accidents and HIV/Aids, for example. While we have no local statistics with regard to VTE in South Africa, we can extrapolate from the UK, which has excellent statistics. In that country the number of people who die annually from a VTE is double the combined death rate of the four aforementioned conditions.’

What are the warning signs of VTE?
In the case of deep-vein thrombosis: pain or tenderness starting in the calf; swelling of the leg, ankle and foot; a warm sensation and redness or discoloration of the leg.
In the case of pulmonary embolism: unexplained shortness of breath, rapid breathing, chest pain that worsens with a deep breath, rapid heart rate and light-headedness or fainting.
It’s important to note, however, that some people do not experience any warning signs or symptoms.

If someone suspects they have an increased risk or they’ve had an episode before, what can they do to prevent VTE?
• If you experience any of the warning signs or symptoms, get medical attention immediately.
• If you require surgery, discuss the risk of VTE, your family history and the possible need for prophylaxis with your healthcare team – and comply with their recommendations.
• Move around as much as possible when travelling.
• Maintain a healthy lifestyle to control your weight.

The information provided in this article was correct at the time of publishing. At Mediclinic we endeavour to provide our patients and readers with accurate and reliable information, which is why we continually review and update our content. However, due to the dynamic nature of clinical information and medicine, some information may from time to time become outdated prior to revision.

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