Role of a Novel Exercise Program to Prevent Post-thrombotic Syndrome

Despite standard care, 25%-50% of patients with clots in the deep veins of the arms and legs progress to chronic post-clot problems resulting in significant disability, loss of productivity, and healthcare costs. Reverse flow in the veins from an organizing clot is the primary cause of post-clot problems. Veins with early clot breakdown have a lower incidence of reverse flow. The investigators have observed that clot breakdown is enhanced by increased blood flow and that moderate arm and leg exercise result in increased venous blood flow. Hence, the investigators predict that a supervised exercise program in patients with deep vein clots could increase leg vein blood flow, accelerate clot breakdown, and decrease the risk of post clot problems. The primary hypothesis is that increased blood flow across the clot (induced by supervised exercise) will increase clot breakdown and decrease severity of post clot problems. The investigators are conducting a randomized clinical trial of standard therapy compared to progressive exercise training in patients with leg deep vein clots.

Standard anticoagulation therapy for acute deep vein thrombosis (DVT) reflects the current short term focus on preventing pulmonary embolism (PE) and recurrent DVT. Despite standard care, 25% to 50% of patients with DVT progress to the chronic post-thrombotic syndrome (PTS) resulting in significant disability, loss of productivity, and healthcare costs. The investigators postulate that a supervised exercise program in patients with acute DVT could increase lower extremity venous flow, accelerate thrombus resolution, and thereby decrease the risk of PTS. If the patient is unable to perform exercises, neuromuscular electrical stimulation (NMES) will be used to induce contraction of the muscles of the lower extremities.

Aim 1 will test whether a 3-month exercise program has long-term clinical benefits in acute DVT. The primary outcome measures will be the 2-year change in Villalta score for PTS and VEINES-QOL score (Venous Insufficiency Epidemiological and Economic Study-QOL).

Aim 2 will evaluate whether exercise therapy in patients with acute DVT enhances thrombus resolution. The outcome measure will be 3-month change in thrombus volume.

Aim 3 will assess the relationship between PTS, venous hemodynamics and exercise capacity. The outcome measures will be Villalta score, common femoral reflux, and 400-meter walk time.

Eligibility Criteria:
Inclusion Criteria:

* Acute Lower Extremity DVT
* DVT documented by ultrasound, CT/Magnetic Resonance imaging (MR) venogram, or conventional venogram
* Enrolled within 4 weeks of onset of symptoms
* Age 18 years or older

Exclusion Criteria:

* Peripheral arterial disease (disabling claudication, rest pain, tissue loss) with ankle brachial index (ABI)\&lt;0.5
* Immediate need for thrombolysis/thrombectomy
* DVT involving the inferior vena cava (IVC)
* Contraindication to anticoagulation
* Contraindications to exercise training
* Medical illness interfering with evaluation/follow-up
* Life expectancy \&lt;2 years
* Pregnancy
* Inability to walk
* Hemodynamically significant PE