Some people continue to have leg swelling, aching, heaviness or skin changes after a deep vein thrombosis (DVT). This long-term complication is called post-thrombotic syndrome. It develops when the clot and inflammation damage veins or their valves, making it harder for blood to return from the leg.
New or suddenly worsening symptoms still need assessment because a recurrent DVT can feel similar. A previous clot should never be used to dismiss a new change.

Key takeaways
- Post-thrombotic syndrome can cause chronic swelling, heaviness, discomfort and skin discolouration.
- Sudden worsening requires assessment for another clot or another cause.
- Compression is not suitable for everyone and should be individually assessed.
- Protecting the skin and maintaining suitable movement can support long-term care.
Why symptoms remain after DVT
A DVT blocks a deep vein and can injure one-way valves that normally help blood travel back to the heart. Even after anticoagulant treatment, residual obstruction or valve damage may leave higher pressure in the lower-leg veins.
Symptoms often worsen after long periods of standing or sitting. They may improve with walking or leg elevation, but patterns vary.

Symptoms to discuss with a clinician
Common features include swelling, aching, heaviness, cramps, itching, tingling, visible veins and darker skin near the ankle. Severe disease can cause eczema-like inflammation or a venous ulcer.
The clinician may compare both legs, examine the skin and pulses, review the original DVT and arrange ultrasound when a new clot or persistent obstruction is suspected.
Management is individual
A plan may include suitable walking and calf-muscle activity, weight management, periods of elevation, moisturising dry skin and properly fitted compression. Compression strength and suitability should be assessed, especially when arterial circulation may also be reduced.
Continue anticoagulants exactly as prescribed. They prevent clot extension and recurrence but do not instantly repair damaged valves. Never change treatment without medical advice.

Red flags after a previous blood clot
Seek urgent care for a sudden increase in one-sided swelling or pain. Chest pain, unexplained breathlessness, coughing blood, collapse or a very fast heartbeat may indicate pulmonary embolism and require emergency attention.
Prompt review is also important for broken skin, spreading redness, fever or a wound that is not healing.
Getting appropriate care in Seremban
For an individual assessment, contact CMH Vascular Surgery service. The appropriate specialty, test or urgency depends on your symptoms, medical history and examination.
This article provides general health information and is not a diagnosis or a substitute for personalised medical advice. Seek urgent medical care for severe or rapidly worsening symptoms.