Vascular and Endovascular Sciences

Vice President:
Vascular Access Society of India

Editorial Board:
Annals of Vascular Surgery

Asian Society of Vascular Surgery

Medanta Hospital, Gurugram, Haryana 122001

World Thrombosis Day 2019: Everything you need to know about blood clots

World Thrombosis Day 2019: Everything you need to know about blood clots

October 23, 2019

Recently, a 19-year-old boy in the city of Hyderabad suffered a brain stroke after playing a trending online game for hours at a stretch. The stroke occurred due to the stressful nature of the game, leading to the development of blood clots in the brain, a condition known as thrombosis. The occurrence of this condition cuts off the blood supply to the rest of the body, resulting in a stroke and other fatalities.

Blood clots (thrombus) are not as uncommon as one thinks and even though they usually dissolve on their own, there is an equal probability that they can travel to other parts of the body like lungs or heart and lead to stroke or cardiac arrest. The most common sign of thrombosis that one tends to ignore is the shooting, persistent pain in the leg. This is because clots cannot be easily spotted and can feel like a noticeable swelling in one leg or inflammation in the leg or arm. Therefore, these signs should not be overlooked basis self-diagnosis and medical intervention should be sought immediately.

Understanding thrombosis

Thrombosis is an abnormal blood clot that forms in the artery or vein and is the one disorder which causes the top three cardiovascular killers, namely, heart attack, stroke and venous thromboembolism (VTE) mostly found in the legs, known as DVT (Deep Vein Thrombosis) and lungs (Pulmonary embolism). The clots are formed through a series of chemical reactions between special blood cells (platelets) and proteins (clotting factors) in blood preventing it from flowing normally through the circulatory system.

According to The Association of Physicians of India, venous thromboembolism (VTE) has higher incidence in the South Indian population as compared to the rest of the population. Higher incidence of VTE have been reported among soldiers posted in high altitude regions of Himalayan ranges. However, there is limited data about the magnitude of Deep Vein Thrombosis (DVT) in Indian population.

Types of thrombosis

Thrombosis is primarily of two types- venous thrombosis caused due a blood clot in the veins (which carry deoxygenated blood back to the heart) and arterial thrombosis caused by a blood clot in the arteries (which carry oxygenated blood from heart to all organs of the body). Their effect on the body depends on the type and location of the clot.

Venous thrombosis

When a blood clot forms in the deep veins of the arms or legs it is called Deep Vein Thrombosis (DVT). If not prevented or detected early, DVT can cause serious medical problems. Pulmonary Embolism (PE) is another type of venous thrombosis when the blood clot in the deep vein of the arms or legs breaks away and travels to the lungs. Together, DVT and PE are known as venous thromboembolism (VTE).

Arterial thrombosis

If a blood clots form in an artery in the heart, it may cut off the flow of blood and oxygen to the heart resulting in a heart attack. Stroke is caused when a blood clot occurs in an artery leading to the brain, disrupting the blood supply.

Risk factors

Blood clots can happen to anyone at any age and sometimes they are not accompanied by warning signs or symptoms, thereby making detection difficult. Therefore, being aware of the risk factors and symptoms can help prevent the formation of a blood clot.

What causes the clots to form?

Blood flow through the veins is helped along by movement of the muscles which squeeze the veins.

Most clots occur because of three factors:

Risk factors for blood clots


Warning signs


DVT and PE are serious, life-threatening conditions that require immediate medical attention. The damage caused by blood clots is usually treated through anti-coagulants, commonly known as blood thinners. These help decrease the clotting power of blood, thereby preventing growth and propagation of a clot. The common blood thinners are heparin, low molecular weight heparin, warfarin and many newer oral anticoagulants like rivaroxaban, dabigatran, apixaban. While the first two (heparin, LMWH) are administered through an injection, rest are taken orally.

If detected early (within 2 weeks), they can also be dissolved by admitting in the hospital through certain injectable medicines known as thrombolytics. If the blood thinners cannot be given to patients for some reasons, a filter can be implanted in the main vein (Inferior Vena Cava) temporarily which is to be taken out once the blood thinners can be started.


The best way to prevent blood clots is to keep moving as immobility increases the risk of developing a blood clot in the legs. Professionals who often sit at their desks for long hours or travel for extended duration must take short breaks in between to stretch themselves and walk around as this is important for maintaining a healthy blood flow.

Keeping other health problems such as diabetes, high blood pressure and high cholesterol in check is also important. Apart from these, consumption of natural blood thinners such as turmeric, ginger, garlic, cayenne peppers, Vitamin E and grape seed extracts can aid prevention. For patients who are hospitalised, assessing the risk of a blood clot becomes very crucial so that preventive measures can be undertaken during and post the hospital stay.
Remember these important points to help reduce your risk of a DVT:

Consult a vascular surgeon for more information and report early if any symptoms are noted in yourself or any near or dear ones, to treat it completely and avoid serious complications.

This article’s author, Tarun Grover, is the Director at Peripheral Vascular and Endovascular Sciences, Medanta, the Medicity.