Ever heard of a medical condition which is caused by a blood clot which lodges inside one of those blood vessels (vein), located deep inside your body and causes one-sided swelling, cramping pain and discomfort on the foot, ankle or calves? Sounds a bit creepy, but yes, there is a condition as such-called Deep Vein Thrombosis.

To shed light on this topic, which is not uncommon and has an incidence of around 1 per 1000 annually in adult populations, we had a discussion with Dr Vindya Wellala, Registrar in Medicine, Teaching Hospital Karapitiya, Galle.

“Often affecting deep veins of the legs, thighs or pelvis, Deep Vein Thrombosis has found to be commonly affecting one’s left leg as a result of the compression of left iliac vein through the right iliac artery” says Dr Wellala. As far as the ‘multifactorial’ causative phenomenon of this condition is concerned medics will be concerned about the following:

• nDamage to the inner layer of the blood vessel due to inflammation  trauma.
• nVenous stasis (stagnation of blood flow hindering the normal drift) due to conditions like varicosis, external pressure on the extremities and long-term immobilisation usually during long hours in flights, bed ridden patients 
• Hypercoagulability (increase tendency for blood clotting) resulted from increased platelet adhesion and medical conditions giving rise to increased clotting tendency (thrombophilia) play the major role.

People exposed to risk
According to the doctor the risk of DVT is unpredictable- but medics would say that if you are suffering from the conditions mentioned below you are exposed to risk. The conditions:

• History of DVT - There is a 30- fold risk 
• History of Pulmonary embolism which usually happens when a blood clot formed in your leg due to DVT, travels to your lungs and blocks a blood vessel. This will lead to low oxygen saturation in your blood which can ultimately damage the lung and other organs possibly causing heart failure, in the end.
• Immobilisation (Long surgeries, long-distance flights, trauma)-There is 20-fold increased risk
• Age > 60 years
• Malignancy
• Family history of hypercoagulability 
• Pregnancy (a natural state of hypercoagulability which increases the tendency to form blood clots)
• Usage of hormonal contraceptives, Hormone replacement therapy
• Obesity
• Smoking

How patients present with the condition 

• Localised and unilateral swelling, feeling of tightness, discomfort or heaviness in limbs particularly calves
• Warmth, erythema, and possibly livid discoloration (signs of inflammation)
• Progressive  dull pain
• Calf pain on dorsal flexion of the foot
• Distention of surface veins
• Possibly palpable cord
• General symptoms like fever
• Possible signs of  distance spread (pulmonary embolism) such as shortness of breath, chest pain.

At certain circumstances they can be associated with other features which are related to systemic disease such as anti-phospholipid syndrome characterised by recurrent miscarriages, migraine like headache.

Many ask whether the pain is felt only the legs? The doctor’s answer is no. “Some people can rarely develop DVT in the upper extremity as well and can present with symptoms including,

• Neck and shoulder pain 
• Pain which radiates down the arm to the forearm
• Swollen arms or hands
• Bluish discoloration of the skin around the affected area
• Weakness in the hand on the affected side

“However, the bad news associated with DVT is that some patients would get diagnosed only when they enter hospital due to Pulmonary Embolism- a medical emergency, occurs as a complication of DVT which takes place when a blood clot from the lower extremity, dislodges and places in a blood vessel carrying blood to the lungs. This is why proper awareness about these medical conditions is extremely important, because having few right facts in your head can save lives before they get complicated with unnecessary trouble-even if you are not a health care professional” highlights Dr. Wellala.

The process of getting diagnosed
We can visualise blood vessels via imaging such as compression ultrasonography with Doppler, which  is the test of choice when it comes to DVT. This is a test in which a combination of ultrasonography to visualise the vein and Doppler to assess blood flow abnormalities is used.However, there are other options such as,

• Blood investigations such as D dimer which indicate you are harboring a possible blood clot  is a product which results from blood clot. D-Dimer testing (95% sensitivity but less than 50% specificity where normal test results rules out DVT yet elevated D-dimers alone are not proof of DVT as it can elevate in some other conditions as well.
• Venography 
• CT Scan in patients suspecting pulmonary embolism or malignancy

Once confirmed with DVT we need to look in to the cause such as hypercoagulable state, internal malignancy, unusual site blood clot specially when there is no provocation factor such as immobilization.

Treatment 
According to Dr. Wellala it is important to seek immediate medical advice once you notice the first signs and symptoms of DVT as it can give rise to life threatening complications, in the event there is a delay.

Initial treatment usually needs inward care and intravenous or subcutaneous medications to prevent further blood clotting. Meanwhile oral medication will be continued such as warfarin which is a blood thinner. 

Lysis of the clot or thrombolytic therapy or removal of the clot by a surgery thrombectomy-used in rare instances in massive proximal DVT. Additionally,

• Compression therapy with bandages and stockings
• Inferior Vena Cava Filters- These are indicated in patients who are at a high risk of developing pulmonary embolism, but contraindicated to go for anticoagulation, thrombolysis, and thrombectomy, However, these filters can only prevent  clot dislodge from lower extremity vessels to lungs  

 Prevention

• Regular exercise-Try your best to move and stretch your legs when you have been sitting for sometime
• Early mobilisation after surgery, pregnancy and post delivery 
• Compression stockings and intermittent compression as indicated by a health care professional during pregnancy post-delivery or when bed ridden sate.
• Avoid certain drugs such as hormonal contraceptives (birth control pills) in patients who are at high risk

Additional food for thought
There are two subtypes of Deep Vein Thrombosis. They are:

• Phlegmasia cerulea dolens

This is a severe form of phlebo-thrombosis which is characterised by the obstruction of all veins of one extremity with subsequent compression of arterial flow and high mortality. In this case you will present with severe swelling, oedema and pain on your limbs associated with coldness, cyanosis (bluish discoloration on the area) and pulselessness.

Complications: Shock, gangrene, acute renal failure (due to Rhabdomyolysis)
Treatment is usually an emergency surgery which is venous thrombectomy or fasciotomy where amputation is kept as the last resort. However Fibrinolysis can be considered in case the surgery fails.

• Paget-Schroetter disease (upper extremity deep vein thrombosis)

This is another form of DVT which is defined as the acute thrombosis of a brachial, axial or subclavian vein. Sometimes called as “Effort-induced thrombosis”, this can be triggered by an extreme activity of the arms during sports, operation of a jackhammer etc. or can be a complication of Thoracic outlet syndrome and lodging a foreign object in veins (central venous catheter, pacemaker lead)
Treatment is usually anticoagulation or fibrinolysis.

Additionally you can develop massive blood clots in your proximal blood vessels which can compress other blood vessels- causing a lack of blood supply to the limb of the affected side, increasing pressure within the limb compartment and causing muscle damage, kidney and impairment. Though it is very rare , it can be a life threatening condition which needs urgent surgery.