从右上肺动脉缺如误诊肺栓塞病例谈肺栓塞现有确诊手段的利与弊

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

目的通过分析肺动脉缺如患者的误诊过程,分析肺通气/灌注显像等肺栓塞确诊手段的特点。方法对我院收治的1例误诊为肺栓塞的右上肺动脉缺如病例资料进行回顾性分析,并针对指南推荐的肺栓塞确诊手段复习相关文献。结果本例为中年男性,以喘憋伴双下肢水肿3周余入院,经相关医技检查诊断为慢性阻塞性肺疾病、慢性肺源性心脏病、右心衰、肺动脉高压、重度阻塞性睡眠呼吸暂停低通气综合征,经肺通气/灌注显像提示双肺多发栓塞(累及5个肺段),补充诊断为肺栓塞,予华法林口服抗凝及对症支持治疗后病情缓解出院。13 d后因咳嗽、咯血再次入院,急查国际标准化比率2.20,停用华法林后观察仍有咯血。行肺动脉、主动脉及支气管动脉造影示:右上肺动脉近段纤细、以远缺如,左下肺动脉纤细,平均肺动脉压35 mm Hg,右下肺支气管动脉迂曲、扩张。修正诊断为右上肺动脉缺如,于病变支气管动脉近端行弹簧圈栓塞术,术后咯血停止。结论肺动脉缺如很难第一时间确诊,多因反复咳嗽、咯血、憋气就诊,常误诊为肺栓塞或支气管扩张等其他呼吸系统疾病,肺动脉造影是诊断该病的"金标准"。肺通气/灌注显像作为肺栓塞的排除性诊断手段对诊断肺动脉缺如价值有限,肺栓塞的诊断应基于医技检查前评估临床诊断的可能性,对高度可能者选择确诊手段,对低度可能者选择排除性诊断检查,最大限度避免肺栓塞的诊断不足和诊断过度。

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 diagnostic procedure was retrospectively collected from an absent right upper pulmonary artery case,initially misdiagnosed as pulmonary 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 mismatch 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 artery pressure was 35 mm Hg. 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 diagnosis 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 exclusion of absent pulmonary artery. The diagnostic value of lung scintigraphy is limited for absent pulmonary artery. The diagnostic 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.