目的:探讨T1 mapping联合钆延迟强化（LGE）对扩张型心肌病（DCM）的诊断价值。方法:选择2018年4月至2019年11月因不明原因急性心力衰竭（心衰）而经超声检查考虑为DCM的32例患者为研究对象；同时纳入同一时间段检查心脏磁共振成像（CMRI）的18例体检者为对照组。采用飞利浦Ingenia 3.0T检查所有受检者心脏，平扫检查项目包括T2加权成像（T2WI）、电影序列、增强前的native T1 mapping；增强检查项目包括延迟增强及增强后post T1 mapping、首过灌注。使用钆喷酸葡胺注射液作为对比剂，首过灌注剂量为0.1 mL/kg，以相同速度追加生理盐水20 mL，延迟7 min开始进行延迟增强序列扫描，包括4层2腔心位和4腔心位。观察LGE联合T1 mapping的CMRI结果，包括心功能指数〔左室舒张期末容积（LVEDV）、左室收缩期末容积（LVESV）、左室射血分数（LVEF）、瓣膜反流〕、心脏形态学指标〔左心室质量（LVM）〕、组织学特点（T2图像心肌信号、有无灌注缺损及其位置和范围、有无延迟增强及其位置、形态和范围、增强前后T1值）、细胞外容积（ECV）及伴随征象（心包积液、胸腔积液）等指标；绘制受试者工作特征曲线（ROC），评价增强前T1 mapping的T1值对DCM的诊断价值；同时观察临床终点事件发生情况。结果:DCM组患者性别、年龄、体重指数（BMI）、血压、心率（HR）、血细胞比容（HCT）、肌酐（Cr）、高血压和心脏病家族史患者比例比较差异均无统计学意义。DCM组患者N末端脑钠肽前体（NT-proBNP）水平和心功能Ⅲ级、糖尿病、吸烟史、饮酒史、用药史患者比例明显高于对照组（均n P<0.05）。与对照组比较，DCM组LVEDV（mL/mn 2：234.9±35.9比121.8±27.6）、LVESV（mL/mn 2：189.7±42.8比54.8±17.0）、LVM（g：197.6±56.3比110.5±22.9）、增强前T1值（ms：1 332.1±35.9比1 272.0±41.0）、ECV 〔（45.7±4.9）%比（28.0±2.1）%〕水平均明显升高；LVEF（0.191±0.107比0.554±0.103）、增强后T1值（ms：453.9±72.7比493.5±43.9）均明显降低（均n P<0.05）。DCM组瓣膜反流、心包积液和胸腔积液患者比例分别为25.0%、18.8%、25.0%。ROC曲线分析显示，T1 mapping增强前T1值的截断值为1 220.22 ms时，ROC曲线下面积（AUC）为0.84，n P＝0.015，敏感度为77.8%，特异度为88.9%，说明固有心肌T1值对诊断DCM有一定参考价值。32例DCM患者中有22例（68.8%）出现LGE，位置为室间隔、下壁壁间或心外膜下，范围为局部或弥漫多发，室间隔和下壁均受累的有9例（28.1%）；平均随访16个月，其中3.1%出现心搏骤停。n 结论:一站式CMRI检查可以提高DCM的诊断效力，T1 mapping联合LGE可提高诊断准确性，对诊断和随访患者治疗很有意义。“,”Objective:To explore the role of T1 mapping and late gadolinium enhancement (LGE) for detection of dilated cardiomyopathy (DCM).Methods:Thirty-two DCM patients detected by ultrasonic testing with unknown origin heart failure from April 2018 to November 2019 were involved. In addition, they were compared with 18 physical examiner under cardiac magnetic resonance imaging (CMRI) in the same period. Phillip's Ingenia 3.0T MRI was used to examine heart function, plain scan included cine, T2 weighted imaging (T2WI) and pre-contrast native T1 mapping. The enhancement scan included perfusion weighted imaging, LGE imaging and post-contrast post T1 mapping. Using gadolinium injection, a bolus of 0.1 mL/kg of gadolinium-based contrast followed by a 20 mL saline flush was administered. After a 7-minute later start scanning, delay enhance sequence was started, including 4 layers, 2 cavities and 4 cavities. LGE and T1 mapping results were observed, including cardiac function indexes [left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), valvular regurgitation], cardiac morphological indexes [left ventricular mass (LVM)], histological characteristics (T2WI myocardial signal, presence of perfusion defect and its position and scope, presence of delayed enhancement and its position, shape and scope, pre- and post-contrast T1 values), extracellular volume (ECV) and the accompanying signs (pericardial effusion and pleural effusion). The receiver-operating characteristic curve (ROC) was drawn, the diagnostic value of T1 value of pre-contrast T1 mapping for DCM was evaluated, and the occurrence of clinical endpoint events was observed.Results:There were no statistically significant differences in DCM patients with gender, age, body mass index (BMI), blood pressure, heart rate (HR), hematocrit (HCT), creatinine (Cr), family history of hypertension or heart disease. In DCM group N-terminal brain natriuretic peptide precursor (NT-proBNP) level and proportion of patients with heart function level Ⅲ, diabetes, smoking history, drinking history and medication history were significantly higher than those in control group. Compared with control group, LVEDV (mL/mn 2: 234.9±35.9 vs. 121.8±27.6), LVESV (mL/mn 2: 189.7±42.8 vs. 54.8±17.0), LVM (g: 197.6±56.3 vs. 110.5±22.9), pre-contrast T1 values (ms: 1 332.1±35.9 vs. 1 272.0±47.0), ECV [(45.7±4.9)% vs. (28.0±2.1)%] were significantly increased in the DCM group; LVEF (0.191±0.107 vs. 0.554±0.103), post-contrast T1 values (ms: 453.9±72.7 vs. 493.5±43.9) were significantly decreased (all n P < 0.05). In DCM group, the proportions of valvular regurgitation, pericardial effusion and pleural effusion were 25.0%, 18.8% and 25.5%, respectively. ROC curve analysis showed that the cutoff value of pre-contrast T1 values was 1 220.22 ms, the area under ROC curve (AUC) was 0.84 ( n P = 0.015), the sensitivity and specificity were 77.8% and 88.9%, indicating that pre-contrast T1 values may be a certain prediction for diagnosis of DCM. In 32 patients with DCM, 22 cases (68.8%) had LGE in position wall, interventricular septum, inferior wall or under the epicardium, with local or multiple diffuse, 9 cases (28.1%) were both interventricular septum and inferior wall involved. During an average of 16 months follow-up, 3.1% patients appeared sudden cardiac death.n Conclusion:One-stop CMRI can improve the diagnostic efficacy of DCM, and T1 mapping with LGE imaging can improve the diagnostic accuracy, which is very meaningful for diagnosis and follow-up of patients.