目的：探讨双源CT血管成像在成人先天性主动脉瓣二瓣化畸形（BAV）诊断中的优势及应用价值。方法：回顾性分析CT诊断为BAV并经手术治疗的44例患者的临床和影像资料，着重观察BAV的影像特征及分型，测量主动脉瓣膜厚度、瓣膜钙化的程度、升主动脉直径及左心室舒张末期横轴径等。以手术病理结果为标准，将44例患者按照超声诊断结果分为两组：超声诊断正确组27例，超声诊断错误组17例，依据患者年龄、性别、二瓣化畸形分型、瓣膜钙化程度、瓣膜厚度、瓣膜功能不全程度进行比较。结果：CT对44例BAV患者均做出明确诊断, 其中5型28例，3型7例，1型5例， 2型4例，4型0例，42例伴有升主动脉扩张，13例有左室扩大，4例冠状动脉高位开口，1例冠状动脉-肺动脉瘘，7例冠状动脉存在有意义狭窄（血管狭窄≥50%）；超声诊断错误组中瓣膜中重度钙化比例（88%）显著高于超声诊断正确组（48%），P＝0.01；瓣膜厚度≥3 mm（88%）比例显著高于超声诊断正确组（33%），P＝0.0019；两组间瓣膜钙化程度、瓣膜厚度差异有显著统计学意义（P＜0.05）。结论：双源CT在BAV诊断方面具有重要价值，能够准确检出和诊断BAV，对瓣膜严重增厚钙化者诊断的准确性优于超声，同时能够全面评估心脏的非瓣膜结构及主动脉和冠状动脉，CTA可作为除超声心动图之外评价主动脉瓣畸形的重要检查方法之一。

Objective: To investigate the advantages and value of dual-source CT angiography in diagnosis of adults with congenital bicuspid aortic valve(BAV). Methods: Clinical and imaging data of 44 patients who were diagnosed as BAV and received surgical treatment were retrospectively analyzed, focusing on the imaging characteristics and type of BAV, the thickness of the aortic valve, the degree of valve calcification, ascending aorta diameter, transverse end-diastole diameter of left ventricular and so on. On the basis of surgical pathology results, according to the echocardiographic results, 44 cases of BAV patients were divided into two groups: 27 cases as truly diagnosed group, and 17 cases as falsely diagnosed group. We compared the results based on age, sex, type of the BAV, valve calcification degree, valve thickness, the extent of valve insufficiency. Results: CT made the definite diagnosis in all 44 cases of BAV patients, among whom 28 cases categorized as type 5, 7 as type 3,  5 as type 1, 4 as type 2, and 0 as type 4. Forty-two cases manifested with ascending aortic dilatation, 13 with left ventricular enlargement, 4 with high ostium of coronary artery, 1 with coronary-pulmonary artery fistula, 7 combined with coronary stenosis(≥50%); Proportion of moderate to severe valve calcification and valve thickness ≥3mm in falsely diagnosed group was significantly higher than that in truly diagnosed group(88% vs 48%, P=0.01; 88% vs 33%, P=0.0019), and the valve calcification and thickness were statistical different between the two groups(P<0.05). Conclusion: Dual-source CT plays an important role in BAV diagnosis, it can make accurate detection and diagnosis of BAV, and diagnostic accuracy for valve thickening of severe calcification is better than that of ultrasonic. At the same time to fully evaluate the valves of the heart structure and the aorta and coronary artery, CTA can be used as an important method to evaluate aortic valve malformation besides echocardiography.