分段注射对比剂结合双期扫描在房颤患者左心耳血栓检测中的应用  

Application of Segmented Injection of Contrast Medium Combined with Biphasic Scanning in the Detection of Left Atrial Appendage Thrombus in Patients with Atrial Fibrillation

作　　者：缪俞凤 莫仁彬 王甜 赖迪 MIAO Yufeng;MO Renbin;WANG Tian;LAI Di(Department of Radiology,Liuzhou People's Hospital Affiliated to Guangxi Medical University,,Liuzhou 545006,China;Guangxi Key Clinical Specialties of Medical Imaging;Liuzhou KeyLaboratory of Molecular Imaging;Graduate School of Guangxi Medical University Address:8WenchangRoad,Liuzhou545006,China)

机构地区：[1]广西医科大学附属柳州市人民医院放射科,广西壮族自治区柳州市545006 [2]广西医科大学研究生院 [3]广西医学影像临床重点专科 [4]柳州市分子影像重点实验室

出　　处：《中国医学计算机成像杂志》2024年第6期674-677,共4页Chinese Computed Medical Imaging

基　　金：广西壮族自治区卫生健康委员会科研课题(Z20200148,Z-B20221300,Z-B20241224)。

摘　　要：目的:探讨分段注射对比剂结合双期扫描在房颤患者左心耳血栓检测中的应用价值。方法:前瞻性纳入因房颤入院行射频消融术的患者60例,随机分为A组、B组,每组30例。患者术前均行左心房CT血管成像(CTA)和经食管超声心动图(TEE)检查。左心房CTA采用320排容积CT行心电门控容积模式扫描,第一期扫描范围为气管隆突上2cm至心脏膈底,二期延迟60s后扫描左心耳。注射方案:A组第一期注射对比剂35~45mL,注射速率4mL/s,同等速率追加生理盐水30mL;第二期注射对比剂25mL,注射速率1mL/s,同等速率追加生理盐水20mL。B组注射对比剂60~70mL,注射速率4mL/s,同等速率追加生理盐水30mL。2名从事心血管影像学诊断的副主任医师采用4分法评价左心房、肺静脉及左心耳等CTA影像。金标准为TEE检查,评价左心房CTA检测左心耳血栓的特异度和阳性预测值。计算2组图像第二期延迟扫描左心耳平均CT值。结果:分段注射对比剂结合分期扫描的A组检测左心耳血栓的特异度(96.1%)和阳性预测值(86.8%)比B组的高。A组二期延迟扫描左心耳平均CT值高于B组,差异有统计学意义。结论:二期延迟60s扫描左心耳结合分段注射对比剂具有较高的诊断价值,值得推广应用。Purpose:To evaluate the effectiveness of segmented injection of contrast medium combined with biphasic scanning in detecting left atrial appendage(LAA)thrombus in patients with atrial fibrillation(AF).Methods:Sixty AF patients scheduled for radiofrequency ablation were prospectively enrolled and randomly divided into two groups:group A(n=30)and group B(n=30).All patients underwent left atrial CT angiography(CTA)and transesophageal echocardiography(TEE)prior to the procedure.The left atrial CTA was performed with a 320-row volume CT scanner in ECG-gated volume mode.The first scan phase covered from 2 cm above the tracheal carina to the diaphragmatic floor of the heart,while the second phase was delayed by 60 seconds to capture the LAA.Injection protocol:In group A,patients received 35-45 m L of contrast medium at an injection rate of 4 m L/s in the first phase,followed by 30 m L of saline at the same rate.For the second phase,25 m L of contrast was injected at 1 m L/s,with an additional 20 m L of saline at the same rate.In group B,60-70 m L of contrast was injected at 4 m L/s,followed by 30 m L of saline at the same rate.Vascular images of the left atrium,pulmonary veins,and LAA were evaluated by two associate chief cardiovascular radiologists using a four-point scale.TEE served as the gold standard for assessing the specificity and positive predictive value of left atrial CTA in detecting LAA thrombus.The average CT values of the delayed LAA scan in the second phase were calculated for both groups.Results:The specificity(96.1%)and positive predictive value(86.8%)for detecting LAA thrombus were higher in group A than in group B.The average CT attenuation in the delayed LAA sacn in group A was significantly higher than in group B.Conclusion:A 60-second delayed scan of the LAA combined with segmented contrast injection offers high diagnostic accuracy and is a valuable approach for clinical application.

关 键 词：心房颤动 分段注射 分期扫描 左心耳血栓 

分 类 号：R445.3[医药卫生—影像医学与核医学]