Common Causes of Lower-Extremity Deep Vein Thrombosis and Its TCM Treatment

Deep vein thrombosis (DVT) of the lower extremities is a condition in which a clot forms in the larger veins of the leg. Its main feature is blood coagulating into a thrombus within a deep vein of the leg, blocking the vessel, impeding blood flow, and possibly causing inflammation. The medical abbreviation is DVT, and it most commonly occurs in the leg. The most typical symptom is sudden unilateral (especially left-sided) leg swelling. During the acute phase, the skin over the swollen area may be red and warm to the touch, hotter than the healthy leg. In severe edema the skin may take on a purplish or mottled appearance, and some patients' legs look as if they had been soaked in water.

Thrombi in the popliteal, femoral, and common iliac veins can travel with venous blood to the right atrium and then into the pulmonary artery, causing pulmonary embolism. Small and medium emboli usually do not cause serious consequences, but a large embolus lodged in the main pulmonary artery or a major branch can cause sudden dyspnea, cyanosis, and shock; severe cases may die of acute respiratory and circulatory failure (sudden death).

Slowed blood flow, a tendency of blood to coagulate, and damage to the vascular intima are the three key precipitating factors; they must act together to produce DVT, which is why DVT is also called Virchow's triad. These three factors are associated with malignancy, trauma, surgery, prolonged bed rest, sedentary sitting, long flights or drives ("economy-class syndrome"), uterine compression of the iliac vein during pregnancy, and injury from chemotherapy drugs.

DVT is common in cancer patients, postoperative patients, and fracture patients, and predominates in people over sixty. In recent years, however, young people (18–45) have increasingly been diagnosed, linked to unhealthy habits such as long office hours, sedentary gaming, and long-distance travel.

In TCM this condition is attributed to binding of stasis-heat. Treatment must address three aspects: one, activate blood and resolve stasis; two, promote urination and reduce swelling; three, clear heat and resolve toxins. In the acute phase, decoctions are appropriate, with large doses of Jinyinhua (Lonicerae Flos), Zhizi (Gardeniae Fructus), Yimucao (Leonuri Herba), Dilong (Pheretima), Mugua (Chaenomelis Fructus), Cangzhu (Atractylodis Rhizoma), Niuxi (Achyranthis Bidentatae Radix), Taoren (Persicae Semen), Honghua (Carthami Flos), and Yiyiren (Coicis Semen).

In elderly or cancer patients with DVT, treatment should not be rushed; pills may be used for gradual effect. My empirical formula for chronic DVT is: Dilong (Pheretima) 40 g, Niuxi (Achyranthis Bidentatae Radix) 40 g, Mugua (Chaenomelis Fructus) 40 g, Yiyiren (Coicis Semen) 40 g, Duzhong (Eucommiae Cortex) 20 g, Xuduan (Dipsaci Radix) 20 g, Fushen (Poriae Sclerotium Pararadicis) 20 g, Yuanzhi (Polygalae Radix) 20 g, Zhizi (Gardeniae Fructus) 20 g, Jinyinhua (Lonicerae Flos) 40 g, Yimucao (Leonuri Herba) 60 g. Grind all finely, refine with honey into small pills 6–10 mm in diameter; take 20–30 pills three times daily after meals. This formula works very well, but the patient must persist. For frail patients add Sheng Huangqi (raw Astragali Radix) 50–100 g and Dangshen (Codonopsis Radix) 30–60 g to the formula.