Benefit and Limitation of Present Diagnostic Methods of Pulmonary Embolism：A Case Study of Absence of Right Upper Pulmonary Artery Misdiagnosed as Pulmonary Embolism

MI Yu-hong; WANG Jing; LIANG Ying; LU Yan-hui; XU Xiao-feng; YAN Shu-feng; GUO Chang

doi:10.3969/j.issn.1002-3429.2015.04.007

Abstract：Objective From collecting the diagnostic information of an absent pulmonary artery case to clarify the characteristics of the different diagnostic techniques for pulmonary embolism. Methods The detailed information of the diag-nostic procedure was retrospectively collected from an absent right upper pulmonary artery case, initially misdiagnosed as pul-monary embolism, and a review of the diagnostic techniques for the diagnosis of pulmonary embolism was conducted. Results A middle-aged man was admitted to our hospital for dyspnea on exertion and bilateral extremity edema for three weeks. After diagnostic procedures, the patient was diagnosed with chronic obstructive pulmonary disease, severe obstructive sleep apnea syndrome, cor pulmonale, pulmonary hypertension, and right heart failure. After lung scintigraphy, perfusion-ventilation mis-match was detected in 5 segments, and the patient was also diagnosed with pulmonary embolism. Warfarin was prescribed for anticoagulation, and the patient was discharged after symptom was relieved. 13 days later, he was hospitalized again for cough and hemoptysis. Laboratory test revealed that his international normalized ratio was 2. 20. Hemoptysis continued for several days after warfarin was stopped. Further assessments besides routine laboratory tests were performed. Pulmonary angiography revealed that the proximal of his right upper pulmonary artery was very thin and the distal was absent. The mean pulmonary ar-tery pressure was 35 mmHg. Bronchial artery angiography identified the hemoptysis associated with distortion and expansion of bronchial arteries in right lower lung and hemoptysis was stopped after bronchial artery embolization. Conclusion The diagno-sis of absent pulmonary artery is very difficult at the early stage. Patients with absent pulmonary artery often complain of cough, hemoptysis, and/or dyspnea. Absent pulmonary artery may be easily misdiagnosed as pulmonary embolism or other pulmonary disorders, such as bronchiectasis. Pulmonary angiography remains as the "gold standard" for the diagnosis or ex-clusion of absent pulmonary artery. The diagnostic value of lung scintigraphy is limited for absent pulmonary artery. The diag-nostic strategies for pulmonary embolism are based on pre-test probability. In order to avoid overdiagnosis and underdiagnosis,the diagnostic tests are recommended for possible cases of pulmonary embolism, and the excluding tests for less possible cases of pulmonary embolism.