NHS Patient Information
Deep vein thrombosis (DVT) complications.
National Health Service
Post-Thrombotic Syndrome
Post-thrombotic syndrome (PTS) is the long-term complication of deep-vein thrombosis (DVT). After a DVT, the deep venous valves are often damaged and the vein can remain partially blocked, leaving the leg with chronic venous hypertension, swelling, aching, skin changes and, in severe cases, ulceration. PTS is common, it affects between 20 and 50% of DVT patients within two years, and it is the single most important cause of long-term morbidity after DVT.
KONCEPT® runs a consultant-led PTS clinic at our Kingston upon Thames clinic. Same-day venous duplex confirms reflux and residual obstruction, the Villalta score is used to grade severity, a written compression and lifestyle plan is built around the published guidance, and where there is iliac vein obstruction or a venous ulcer that has not responded, specialist referral pathways are set up.
At a glance
Service
Consultant-led
First visit
Duplex + Villalta
First-line
Compression
Initial consult
from £325
Verified statistics
Drawn from NHS, NICE NG158, the European Society for Vascular Surgery, the AHA Scientific Statement on PTS, the Villalta validation studies, the SOX and ATTRACT randomised trials and the EVRA RCT. Every figure links to its citation in the References section at the bottom of this page.
How common PTS is
Treatment evidence
Iliac stent
specialist referral can substantially relieve symptoms in confirmed iliac obstruction or May-Thurner
ESVS[5]
Post-thrombotic syndrome is the chronic state that develops after a deep-vein thrombosis. The clot itself usually resolves over weeks to months, but the damage it leaves behind can be permanent[1][3][5]:
PTS is not the same as a new DVT, and it is not the same as a venous leg ulcer. It is the underlying physiology that drives both the chronic symptoms and, in some patients, a venous ulcer.
Symptoms
Symptoms typically start months to years after the DVT and tend to be persistent or progressive.
Villalta score
The Villalta score is the international clinical standard for diagnosing and grading post-thrombotic syndrome[6][7]. It scores five symptoms reported by the patient (pain, cramps, heaviness, paraesthesia, pruritus) and six clinical signs (pretibial oedema, induration, hyperpigmentation, redness, venous ectasia, calf compression pain), each 0 to 3, plus the presence or absence of a venous ulcer.
Below the diagnostic threshold for PTS.
Day-to-day symptoms but limited functional impact. Compression and lifestyle measures are first-line.
Significant impact on daily function. Class 2 or 3 compression, treat any superficial reflux, optimise lifestyle.
Marked functional impact or a venous ulcer. Full leg-ulcer pathway, Class 3 compression, consider iliac vein investigation and stenting referral.
Your consultant will use the Villalta score at your first visit, and again at follow-up, to measure your response to treatment objectively.
Risk factors
Not every DVT leads to PTS. The published evidence shows the strongest predictors are[3][5][6]:
May-Thurner syndrome (compression of the left common iliac vein by the right common iliac artery) is a separate but related cause of left-sided iliofemoral DVT and chronic iliac vein obstruction. It is treatable by iliac vein stenting via specialist referral.
Diagnosis
Our work-up follows ESVS guidance and uses the Villalta score[5][6]:
Initial venous consultation with duplex ultrasound is £325 (one leg) or £495 (both legs). Please see the pricing page for the full schedule.
Management
PTS management is compression first, with treatment of any contributing superficial vein reflux, attention to risk factors and lifestyle, and specialist referral where iliac obstruction or refractory ulceration is identified.
Medical-grade graduated compression is the cornerstone of PTS management[3][5][10]. Typical prescription is Class 2 (18 to 24 mmHg) for mild-to-moderate PTS, and Class 3 (25 to 35 mmHg) for severe PTS. Garments are fitted by our compression specialist following an ABPI safety check, and replaced every 3 to 6 months. See Compression therapy fitting for the full pathway.
Where duplex shows symptomatic superficial vein reflux contributing to the venous hypertension, endovenous closure (EVLA, RFA, VenaSeal, ClariVein or foam sclerotherapy) reduces overall venous pressure and, in patients with a venous ulcer, reduces ulcer recurrence (EVRA randomised trial)[9]. See Varicose vein treatment.
For patients with a current or recurrent venous leg ulcer in the context of PTS, full leg-ulcer management runs alongside (TVN-led wound care + compression + treatment of the cause). See Leg ulcer treatment.
For patients with confirmed iliac vein obstruction (most commonly post-thrombotic iliac scarring, or anatomical compression in May-Thurner), iliac vein stenting by specialist endovascular referral can substantially relieve symptoms[5].
KONCEPT® does not perform iliac vein stenting at the Kingston clinic. Cross-sectional venography and any stenting are arranged at a suitable specialist centre, with the second opinion, pre-intervention planning and post-procedure follow-up at KONCEPT®.
Anticoagulation prevents DVT recurrence and progression but does not directly treat established PTS[3]. Decisions about anticoagulation duration and choice are made in collaboration with your GP and your usual anticoagulation team.
First visit
For full pre-care and post-care instructions, see our Patient instructions page. PTS sits alongside the compression and wound-care pathways in that guide.
You receive a written quote before any treatment is booked.
Insurance
PTS assessment and treatment is recognised by most major UK private medical insurers when there is a clinical indication, particularly where symptoms affect daily life or where there is recurrent ulceration. Cover for ongoing compression, wound care and any onward iliac vein referral varies by policy.
Recognition at KONCEPT® is at both clinic and consultant level, and cover is expanding. Call 020 8129 1011 with your insurer and policy details and we will come back to you within one working day with confirmation, before any appointment is booked.
Read more on the Insurance & access page →
Your consultants and team
PTS consultations at KONCEPT® are carried out by one of our Consultant Vascular Surgeons, both on the GMC Specialist Register for Vascular Surgery and both Platinum BUPA Consultants. They hold substantive NHS consultant posts at St George’s University Hospitals NHS Foundation Trust and see private patients here on a practice-privileges basis.
Day-to-day compression fitting is delivered by our compression specialist, and wound care for any active venous ulcer by our Tissue Viability Nurse (NMC registered).
FAQs
Post-thrombotic syndrome (PTS) is the long-term complication of deep-vein thrombosis (DVT). After a DVT, the deep venous valves are often damaged and the vein can remain partially blocked, leaving the leg with chronic venous hypertension, swelling, aching, skin changes and, in severe cases, ulceration. It affects between 20 and 50% of DVT patients within two years.
Common symptoms are leg heaviness, aching, swelling around the ankle that worsens through the day, cramping leg pain on walking (venous claudication) that is relieved by rest and elevation, skin changes such as discolouration or eczema, and in severe cases a venous leg ulcer. Symptoms typically start months to years after the DVT.
PTS is diagnosed clinically using the Villalta score, supported by venous duplex ultrasound to map deep and superficial reflux and any residual venous obstruction. Cross-sectional venography (MRV or CTV) by specialist referral is used where iliac vein obstruction or May-Thurner is suspected.
The Villalta score is the international standard for grading PTS. It combines five patient-reported symptoms and six clinician-assessed signs, each scored 0 to 3, plus the presence or absence of a venous ulcer. Scores of 5 to 9 indicate mild PTS, 10 to 14 moderate, 15 or higher (or any ulcer) severe.
Partly. The single most important step is appropriate anticoagulation in the first three months after a DVT, with early ambulation and early compression. Once PTS has developed, it cannot be reversed but it can be controlled.
Compression therapy is first-line and the cornerstone of management. Lifestyle measures (walking, weight, elevation, skin care), treating any contributing superficial vein reflux, full leg-ulcer pathway management if there is an ulcer, and iliac vein stenting by specialist referral for confirmed iliac obstruction or May-Thurner are the next layers.
May-Thurner syndrome is compression of the left common iliac vein by the overlying right common iliac artery, a normal anatomical variant that can cause left-sided iliofemoral DVT and chronic iliac vein obstruction. It is treatable by iliac vein stenting via specialist endovascular referral.
Most PTS patients do not. Iliac vein stenting is reserved for patients with confirmed iliac vein obstruction on cross-sectional venography (MRV or CTV) and persisting symptoms despite optimal compression and conservative management. Where indicated, your consultant will refer you to a specialist endovascular centre.
Yes, and you should. Walking and calf-muscle pump activity are part of PTS management. Wear your compression while exercising, elevate the leg afterwards if it swells, and avoid prolonged static standing where possible.
Yes. Medical-grade graduated compression is the cornerstone of PTS symptom control. Correctly fitted Class 2 or Class 3 stockings reduce ankle swelling, leg heaviness and the risk of ulcer recurrence. Garments are fitted by our compression specialist after an ABPI safety check.
Yes, recurrence is common in PTS unless the underlying cause is treated. Around 5 to 10% of PTS patients develop a venous ulcer at some point. Treating any contributing superficial vein reflux (EVRA evidence) and lifelong compression substantially reduce recurrence risk.
For self-pay, no, you can book directly. Most insurers also allow direct booking. A small number still require a GP referral letter, we will confirm what your insurer needs when you enquire.
Most major UK private medical insurers cover PTS assessment and treatment where there is a clinical indication. Cover for ongoing compression, wound care and any onward iliac vein referral varies by policy. Call 020 8129 1011 with your insurer and policy details before booking.
The first appointment is 30 to 45 minutes with a Consultant Vascular Surgeon, plus ABPI and venous duplex on the same visit. Allow 60 to 90 minutes for your visit including arrival, reception and the scan.
Surrey catchment also includes Esher, Cobham, Weybridge, Walton-on-Thames, Oxshott and Hampton.
Related vascular services
To book a PTS consultation with one of our Consultant Vascular Surgeons, or to discuss your case, get in touch.
Email info@konceptmedicalclinic.com · Visit 46-48 Wood Street, Kingston upon Thames, KT1 1UW · See full self-pay pricing →
Regulation and standards
KONCEPT® Medical Clinic is registered with the Care Quality Commission (CQC) for the regulated activities provided at our Kingston upon Thames premises. All consultants are on the General Medical Council (GMC) Specialist Register for Vascular Surgery and remain personally accountable to the GMC under Good Medical Practice. Allied-health clinicians supporting the PTS service are registered with their relevant professional bodies (NMC for the Tissue Viability Nurse). Information on this page is written to be factual and verifiable in line with the Committee of Advertising Practice (CAP) Code and Advertising Standards Authority (ASA) rules for medical advertising.
Claims about prevalence, severity grading, diagnosis, management and outcomes on this page are drawn from NHS, NICE NG158, the European Society for Vascular Surgery, the American Heart Association Scientific Statement on PTS, the Villalta validation studies, the SOX and ATTRACT randomised trials and the EVRA RCT. Each source is linked for verification.
Deep vein thrombosis (DVT) complications.
National Health Service
Post-thrombotic syndrome.
BUPA
Venous thromboembolic diseases, diagnosis, management and thrombophilia testing (NG158).
NICE, March 2020, last updated 2023
Quality Standard QS29, Diagnosis and management of venous thromboembolic diseases.
NICE
Management of Chronic Venous Disease, Clinical Practice Guidelines of the European Society for Vascular Surgery (ESVS).
European Journal of Vascular and Endovascular Surgery 2015, 49(6), 678-737
The post-thrombotic syndrome, evidence-based prevention, diagnosis and treatment strategies, a Scientific Statement from the American Heart Association.
Circulation 2014, 130(18), 1636-1661
Assessment of validity and reproducibility of a clinical scale for the post-thrombotic syndrome.
Haemostasis 1994, 24(1), 158a (Villalta score original reference)
Pharmacomechanical Catheter-Directed Thrombolysis for Deep-Vein Thrombosis (ATTRACT).
New England Journal of Medicine 2017, 377(23), 2240-2252
A randomized trial of early endovenous ablation in venous ulceration (EVRA).
New England Journal of Medicine 2018, 378(22), 2105-2114
Compression stockings to prevent post-thrombotic syndrome, a randomised placebo-controlled trial (SOX).
The Lancet 2014, 383(9920), 880-888
Last clinical review: Dr Maryam Attarzadeh, Medical Director (GMC 7193218), 2026-05-28. Next review due: 2026-11-28. Statistical claims are re-verified every 6 months, or sooner if peer-reviewed evidence changes.