Pulmonary thromboendarterectomy (PTE) can provide a surgical cure for the pulmonary hypertension of chronic pulmonary embolism. This form of pulmonary hypertension often goes unrecognised, yet it is progressive and carries a high mortality. Many physicians are unaware that a corrective operation exists, and rely instead on referral for transplantation or merely palliative medical treatment. PTE is technically demanding for the surgeon, and requires careful dissection of the pulmonary artery planes and the use of circulatory arrest. Excellent short and long term results can be achieved, however, and increased awareness of both the prevalence of this condition and the possibility of a surgical cure should avail more patients of the opportunity for relief from this debilitating and often fatal disease.

Acute pulmonary embolism has been said to result in more than 600 000 symptomatic episodes in the United States each year, and to be the principal cause of death in 200 000 patients.1 However, this may be an underestimation as necropsy studies have shown that the diagnosis of acute pulmonary embolism was unsuspected in 70–80% of patients in whom it was the principal cause of death.2 ,3The majority of surviving patients appear gradually to resolve their pulmonary emboli over time. However, complete resolution of embolic material does not always occur; the pulmonary clots then organise, and narrow or occlude the pulmonary arterial branches—pulmonary hypertension results.

How many patients affected by acute pulmonary embolism develop chronic sequelae? The natural history of acute pulmonary embolism is not entirely clear as most patients are not followed serially with lung scans or echocardiography, and acute pulmonary embolism is an underdiagnosed condition. However, significant pulmonary hypertension due to chronic pulmonary embolism is not a rare disease. Presti4 found chronic massive thrombosis of major pulmonary arteries in nearly 1% of 7753 necropsies. Many patients …