PTS - Post Thrombotic Syndrome
By Natalie S. Evans, MD, MS
A 68-year-old man with recurrent deep vein thrombosis (DVT) presented with a difficult-to-heal venous ulcer on his left ankle. He had significant, dramatic skin changes (see image). The patient reported that any type of exercise caused his leg to become swollen and painful.
We diagnosed the patient with the post-thrombotic syndrome (PTS), a constellation of signs and symptoms that occurs in 20 to 50 percent of patients with proximal DVT despite standard anticoagulant therapy.
Background and Diagnosis
Symptoms of PTS may range from mild to severe and may wax and wane. The condition can be severely debilitating, causing not only leg ulcers and changes in leg skin color, but also activity-limiting venous claudication and disability.
PTS is characterized by:
- heaviness of the legs;
- “bursting” sensation when walking;
- itching, burning, tingling, swelling, redness, tenderness in the legs.
PTS may increase the cost of DVT treament by up to 75 percent (Aashrani, J. J Thromb Thrombolysis. 2009; 28:465), and up to two million work days are lost each year due to venous ulcers.
Risk Factors and Severity Scale
Recurrent DVT, especially in the same leg, is the strongest single risk factor for PTS. Other risk factors include older age, higher BMI and subtherapeutic dosing of initial anticoagulation.
PTS usually develops within the first one to two years after DVT. The diagnosis is clinical; there is no gold standard test for the condition. The diagnosis of PTS should be deferred until after the acute phase of thrombosis, i.e., after the first three months.
The Villalta scale is used to diagnose PTS and grade its severity. Five signs (e.g., cramps, pain) and six symptoms (e.g., erythema, pain upon calf compression) are ranked on a scale of zero to three (none, mild, moderate, severe), and the scores are totaled to determine severity (5-9: mild; 10-14: moderate; ≥ 15 [or ulcer]: severe). The Villalta scale is valid and reliable, and it is the diagnostic scale recommended by the International Society on Thrombosis & Haemostasis.
Treatment and Prevention
In this case, the patient’s first DVT, which was anatomically extensive, occurred when he was 56 years old. The patient reported that he subsequently suffered from venous ulcers for years and received skin grafts on two occasions that were unsuccessful. The patient experienced a second DVT when he was 64 years old.
Patients with acute symptomatic DVT should be custom-fitted with graduated compression stockings with 30-40 mmHg compression - not just TED hose. Current clinical guidelines recommend that the stockings be worn for two years, and they can be worn longer if the patient finds them helpful.
In addition to fitting the patient in this case with the tightest compression stockings that he could tolerate, we recommended physical therapy. Anecdotally, walking and pool exercises have been found to be helpful. Patients also can benefit from elevating their legs. In this patient’s case, his wife encouraged him to buy a laptop so that when he was working on his computer, leg elevation would be easier.
Ongoing Research—ATTRACT Study
Treating patients with PTS can be discouraging, because treatment options are limited. PTS is a poorly understood and studied condition for which we have limited evidence-based treatment and prevention options.
The case discussed here illustrates the importance of future and ongoing research in this area, such as the multi-center, randomized clinical trial called the ATTRACT Study, which is sponsored by the National Heart Lung and Blood Institute (NHLBI). Cleveland Clinic is serving as a research site for the study and currently is enrolling patients.
The ATTRACT study is evaluating the use of pharmacomechanical catheter-directed thrombolysis (PCDT) to rapidly eliminate venous thrombus in an attempt to prevent PTS.
More information is available by contacting the ATTRACT Study Clinical Coordinating Center toll-free at 866.974.CLOT (974.2568).
Dr. Evans is a vascular internist in the Section of Vascular Medicine within Cleveland Clinic’s Heart & Vascular Institute. She is board certified in internal medicine and vascular medicine, with specialty interests in PTS, DVT, peripheral artery disease and general vascular medicine.