[Two cases of chronic pulmonary thromboembolism diagnosed clinically as chronic obstructive pulmonary disease].

Two cases of chronic pulmonary thromboembolism accidentally diagnosed in the clinical evaluation of COPD are reported. Case 1, a 69-year-old woman who had never smoked, was given a diagnosis of COPD since she had exertional dyspnea with obstructive pulmonary dysfunction and multiple low attenuation areas on her chest CT. Pulmonary ventilation and perfusion scintigram showed mismatched defects and as chronic pulmonary thromboembolism (CPTE) was finally diagnosed. Case 2, a 70-year-old former smoking man had also been previously given a diagnosis of COPD. He had exertional dyspnea, hypoxemia and multiple low attenuation areas in chest CT. Nonetheless his pulmonary function was normal. Pulmonary ventilation and perfusion scintigram showed mismatched defects and pulmonary angiography identified a floating thrombus in the pulmonary artery. Thus he CPTE was diagnosed. The diagnosis of CPTE in COPD is not easy. Physicians should recognize that CPTE can be associated with COPD and perform further examinations including pulmonary ventilation and perfusion scintigram when patients do not show typical results and/or adequately respond to conventional therapy for COPD.