The American College of Chest Physicians (ACCP) published its latest (8th edition) guidelines for antithrombotic treatment of thromboembolic diseases in Chest in 2008, which is conducive to standardizing the treatment of venous thromboembolic diseases in China by studying and learning from ACCP-8 in Europe and the United States!
1.Deep vein thrombosis (DVT) of lower extremity
1.1 Anticoagulation treatment of DVT of lower limbs DVT of lower limbs is not terrible in itself, and the purpose of its treatment is to prevent and reduce the incidence and death rate of pulmonary embolism (PE), to prevent the recurrence of thrombosis, to restore venous patency, to preserve valve function, and to reduce the incidence of post-thrombosis syndrome (PTS) of lower limb veins. The incidence of post-thrombosis syndrome (PTS) is reduced. Anticoagulation is the most commonly used treatment for DVT and is the core and foundation of all VTE treatment, as it prevents the spread and recurrence of venous thrombosis and reduces the incidence of PE and mortality.
ACCP-8 recommends early anticoagulation for all patients with DVT without contraindications and makes anticoagulation the basis for all other treatments, emphasizing the need for immediate implementation of rapid-acting anticoagulation for patients with a clear diagnosis or high suspicion of lower extremity DVT, regardless of the anticoagulation method used. These rapid-acting anticoagulation methods include subcutaneous low molecular heparin (LMWH), intravenous or subcutaneous plain heparin, or subcutaneous pentosan sodium (fondaparinux). Of course, of these rapid-acting anticoagulants, LMWH is generally recommended, unless the patient also has severe renal insufficiency, in which case plain heparin is preferred. If a vitamin K antagonist (VKA), i.e. warfarin, is required, it should be administered orally from day 1 of anticoagulation therapy and combined with other anticoagulants for at least 5 d. Heparin should not be discontinued until warfarin achieves its anticoagulation goal (INR 2.0-3.0).
1.2 There is still much clinical controversy regarding the duration of long-term anticoagulation therapy. Of course, the longer the anticoagulation therapy, the better, because anticoagulation requires strict monitoring of coagulation function (especially oral VKA), otherwise it is easy to have insufficient anticoagulation effect or overdose leading to bleeding; while non-oral drugs, even subcutaneous LMWH, are relatively cumbersome in use. Therefore, anticoagulation therapy should be appropriate so that the clinical patient can obtain the maximum benefit-risk ratio.
For patients with temporary or reversible risk factors (e.g., bed-ridden due to surgery, trauma, etc., and patients with idiopathic DVT with a distal thrombus for the first time), anticoagulation may be considered for 3 months.
For patients with idiopathic DVT, anticoagulation may be considered for 6 months, and for 3 months for first-time disease, but after 3 months the benefit-risk ratio needs to be re-evaluated, and long-term anticoagulation is considered if the benefit is significant, or recommended if it is a recurrence.
In patients with DVT in combination with tumors, long-term anticoagulation is recommended, and subcutaneous LMWH is recommended for an initial period of 3-6 months.
For all patients requiring long-term anticoagulation, the benefit-risk ratio should be evaluated periodically. The duration of anticoagulation varies with individual circumstances. In general, if the patient has a high benefit, continue anticoagulation, and if the patient has a high risk, stop anticoagulation.
For all patients with DVT, ACCP-8 recommends that the INR should reach the target range of 2.0 to 3.0 during anticoagulation with VKA. For patients with idiopathic DVT, after 3 months of strict anticoagulation, if the patient strongly desires to reduce the number of INR monitoring, a lower intensity of anticoagulation can be considered, targeting 1.5 to 1.9. Whether this range of anticoagulation is appropriate for the national population is still inconclusive, and some domestic experts suggest that Asian patients have lower coagulation function and are more prone to bleeding than patients in Europe and the United States, and recommend the use of lower intensity anticoagulation. therapy.
1.4 Application of Thrombolysis and Thrombolysis ACCP-8 recommends that for some patients with proximal DVT (e.g., iliac femoral DVT) in the acute phase (usually within 14 d of onset), subcatheter thrombolysis, subcatheter thrombolysis combined with thrombectomy, or open surgical thrombectomy may be considered if there are no contraindications such as bleeding. The effect of these operations is mainly to reduce the symptoms in the acute phase and to decrease the incidence of post-thrombotic syndrome (PTS). However, the guidelines clearly suggest that the intensity and duration of anticoagulation therapy for patients remains the same regardless of whether thrombolysis or embolization is taken.
1.5 Vena cava filters in DVT ACCP-8 does not recommend the routine use of vena cava filters in patients with DVT, but only in patients with anticoagulation contraindications and proximal DVT; it also states that anticoagulation should be added as soon as the patient’s contraindication to anticoagulation is removed. The guidelines state that filter placement does not correlate with the rate of VTE recurrence. In this case, the purpose and role of anticoagulation remains to stop the spread of the thrombus and prevent the development of PE.
1.6 Other Patients with acute DVT are encouraged to move as early as their condition allows to reduce pain and edema. Use elastic stockings or elastic bandages as soon as possible after anticoagulation therapy and bring the pressure in the foot and ankle to 30-40 mmHg (1 mmHg = 0.133 kPa) for a minimum of 2 years, or longer if post-thrombotic syndrome develops. In patients with post-thrombotic syndrome, elastic stockings are recommended for mild edema without combined ulcers; for severe edema, intermittent inflatable compression therapy (IPC) can be considered; for venous ulcers, in addition to local treatment of the wound, elastic stockings or IPC are recommended, and the application of drugs such as diosmin and hexaconitine can also be considered.
2.Acute pulmonary embolism (PE)
2.1 Duration and intensity of anticoagulation for PE ACCP-8 recommends long-term anticoagulation for patients presenting with PE at the first episode of VTE, if there is no risk of bleeding and coagulation can be well monitored. Other aspects of anticoagulation therapy are basically the same as those described above for DVT, and the choice, duration and intensity of anticoagulation therapy can be referred to the aforementioned anticoagulation therapy for DVT. It can be seen that, like DVT, anticoagulation is the most important and basic treatment method for PE.
2.2 Thrombolysis and Thrombectomy in PE ACCP-8 recommends that all patients with PE should undergo immediate risk stratification and that thrombolysis is not recommended for most patients. Stratification is based on the patient’s clinical presentation and impaired cardiac function, with a high mortality rate of 58% in hemodynamically unstable or shocked patients and only 15% in hemodynamically stable patients. In patients with hemodynamic instability, immediate systemic thrombolytic therapy is recommended in the absence of significant contraindications to bleeding. The guidelines recommend thrombolysis via peripheral veins for a short period of time (e.g., 2 h of intravenous application) as opposed to thrombolysis with pulmonary artery placement. For most patients with PE, the guidelines do not recommend pulmonary artery catheter intervention; catheter-based local thrombolysis, catheter-based embolization, or surgical embolization should be considered only for those patients at risk of severe bleeding or in poor general condition, and only if skilled physicians and appropriate equipment are available.
2.3 Role of vena cava filters in PE As with the use of filters in DVT, the guidelines do not recommend the routine use of vena cava filters in patients with PE; they are recommended only for patients with contraindications to anticoagulation, such as bleeding risk, and routine anticoagulation should still be performed as soon as the contraindication is resolved.
2.4 Treatment of chronic thromboembolic pulmonary hypertension (CTPH) has been studied and the incidence of CTPH is 0.8% to 3.8% within 2 years after PE. For all patients with CTPH, guidelines recommend lifelong oral VKA anticoagulation to control INR to 2.0-3.0. For some patients (e.g., central), pulmonary artery thromboembolic endarterectomy may be considered with an experienced medical team, and preoperative or intraoperative placement of a vena cava filter may be considered.
3.Other
3.1 Treatment of thrombotic superficial phlebitis For thrombotic superficial phlebitis due to intravenous infusion, ACCP-8 recommends oral diclofenac sodium or other nonsteroidal anti-inflammatory drugs (NSAIDs); or topical topical diclofenac ointment or heparin ointment (Evidence 2B) for 2 weeks or until symptomatic relief; systemic anticoagulation is not recommended.
3.2 Treatment of superficial vein thrombosis For patients with spontaneous superficial vein thrombosis, ACCP-8 recommends anticoagulation for 4 weeks, either with LMWH, heparin, or oral VKA (target INR 2.0 to 3.0); the addition of NSAIDs to anticoagulation is not recommended.
3.3 Treatment of upper extremity DVT ACCP-8 recommends that the approach, intensity, and duration of anticoagulation for upper extremity DVT should be based on lower extremity DVT. For most patients, the guidelines oppose routine thrombolysis; catheter thrombolysis is recommended only for those patients with severe symptoms who are not at risk for bleeding. The guidelines also do not recommend routine catheterization or surgical thrombectomy or angioplasty for most patients; these procedures may be considered for patients with first-time disease who have failed anticoagulation or thrombolytic therapy and have persistent symptoms. Superior vena cava filters are recommended only for those with contraindications to anticoagulation and DVT re-progression or definite PE.
Upper extremity DVT is often associated with the placement of a central venous catheter, but its removal is not recommended in cases where the catheter is still clinically indicated. Anticoagulation for VTE has evolved from plain heparin to LMWH to newer anticoagulants represented by pentosan sodium, with a trend toward simpler and safer anticoagulation, but oral VKA is still the mainstay of long-term anticoagulation.