Chronic thromboembolic pulmonary hypertension
From Standard of Care
Progressive process which is debilitating and caused by abnormally resolved thromboembolic material in the pulmonary vasculature.
Defined as mean pulmonary artery pressure greater than 25 mm Hg that persists 6 months after pulmonary embolism is diagnosed.
Occurs in 2-4% of patients after acute pulmonary embolism.
True incidence is unknown because acute emboli events often occur without symptoms, and even symptomatic pulmonary embolism is overlooked or misdiagnosed.
Frequency among patients with pulmonary hypertension is unknown.
Generally present in their 40s.
Diagnosis often overlooked because of a lack of a history of a history og acute pulmonary embolism.
5-year survival rate of 10-30%.
Symptoms include shortness of breath and right sided heart failure.
Death usually due to progressive pulmonary hypertension and right heart failure.
Increased risk for thrombophilia and genetic predisposition.
Thyroid disease is a risk factor.
Diagnosis is usually made following ventilation perfusion radionuclide scanning or helical CT scans of the chest with measurement of pulmonary hemodynamics.
Severity of the disease measured by echocardiography, and pulmonary angiography.
Treatment for pulmonary hypertension is pulmonary thromboendarterectomy with a mortality rate of 4.4%.
Pulmonary endarterectomy requires circulatory arrest with ischemia for up to 20 minutes, as a totally bloodless field is required to perform the procedure, otherwise, the procedure will be inadequate or perforation of the pulmonary artery may occur.
Presently no drug therapy can prevent the process, except for anticoagulation with or without fibrinolysis treatment.
Fibrinolytic treatment in hemodynamically stable patients with acute pulmonary embolism and right ventricular dysfunction can decrease the frequency of chronic thromboembolic pulmonary hypertension (Kline JA et al).