成人孤立性左室心肌致密化不全的少见MRI表现

Atypical magnetic resonance imaging features in adult isolated left ventricular non-compaction

目的:探讨成人孤立性左室心肌致密化不全(ILVNC)的少见MR表现,提高对该病的诊断及鉴别诊断能力。方法:回顾性分析本院2009年8月-2017年12月经心脏超声及MRI共同诊断的20例成人ILVNC的MR影像资料(诊断标准为舒张末期致密化不全节段心肌厚度与致密心肌厚度比值大于2.3),所有患者均行心肌短轴快速自旋回波TSE-T_1WI及TSE-T_2WI脂肪抑制序列及全心短轴电影序列,其中14例行增强扫描,6例行胸部CT平扫检查。1例最终行心脏移植。20例ILVNC中男13例,女7例,年龄15~68岁,平均年龄(39±3)岁。结果:同时合并右室心肌致密化不全者5例。左室心肌致密化不全心尖段受累最多,共17个节段(85.0%,17/20),3例心尖未受累,第2、3、8、9节段所有患者均未受累;3例特殊表现病例(2例致密化不全节段单独累及心尖且伴心尖室壁瘤样膨出,表现为数个粗大肌小梁突入腔内,1例单独累及心底下壁第4节段,同样表现为数个粗大肌小梁突入腔内);1例ILVNC于胸部CT见散在心内膜下钙化影;2例ILVNC出现心尖部血栓,1例血栓位于心尖部心内膜下,1例血栓位于致密化不全心肌的粗大小梁间隙内,增强后电影序列得以显示清晰;14例增强扫描中,6例共84个节段出现延迟强化(致密化不全节段29个,正常节段55个),强化以心内膜下分布为主,部分呈透壁样,部分位于右室插入点。心脏移植病理符合心肌致密化不全改变。结论:除典型的心肌两层结构之外,ILVNC可以出现其他不典型MR表现及伴随征象,心脏MR能够很好地显示并诊断此病。

Objective:To analyze the atypical cardiac magnetic resonance imaging(CMRI)findings in patients with adult isolated left ventricular non-compaction(ILVNC),and to improve the differential diagnostic skills in clinical work.Methods:The cardiac MR images of 20 patients with ILVNC diagnosed with CMRI and echocardiography in our centrefrom August 2009 to December 2017 were retrospectively analyzed.An end-diastolic ratio between non-compacted and compacted layers greater than 2.3 was considered as diagnostic criteria.TSE-T 1WI and TSE-T 2WI with fat suppression sequences and whole-heart TrueFISP Cine sequences in short-axis view were performed in all patients,of which 14 were performed contrast enhanced scan,6 patients were performed chest CT and 1 patient underwent heart transplantation ultimately.20 patients included 13 males and 7 females with age ranging from 15 to 68 years old(mean age39±3).Results:Right ventricular non-compaction was concurrently detected in 5 patients.The left apex was the most frequently affected segment in 17 of 20 patients(85.0%,17/20),2-,3-,8-and 9-segments were not affected in all patients.The prominent trabecular in apex with apical bulging similar to ventricular aneurysm in 2 patients,and focal ventricular non-compaction with prominent trabecular in single 4-segment in 1 patient was found as uncommon sign of ILVNC.Scattered subendocardial calcifications in left ventricle were detected in 1 patient on chest CT scan.Apical thrombus was found in 2 patients,in which one thrombus localized in apical deep intertrabecular recesses,which was only detected in contrast cine TrueFISP sequence.Delayed enhancement was seen in 84 segments of 6 patients,including 29 non-compaction segments and 55 normal segments.The patterns of enhancement included subendocardial,transmural and patchy enhancement in right ventricular insert points.The pathology result of ILVNC was confirmed in 1 patientof heart transplantation.Conclusion:In addition to the typical two-layer structure of myocardium,other atypical manifestations and concomitant signs can be detected in ILVNC,and CMRI has excellent ability for displaying and diagnosis of ILVNC.