左心室心肌致密化不全患者致密层心肌Native T1值与基质金属蛋白酶-9的相关性研究

目的:应用心脏核磁共振(CMR)Native T1 mapping定量检测左心室心肌致密化不全(LVNC)患者致密层心肌纤维化程度,并探索该指标与心肌重构指标血清基质金属蛋白酶-9(MMP-9)之间的关系。方法:研究纳入2008年12月至2014年6月期间在北京协和医院就诊,经两名资深的心内科医师通过超声心动图检查确诊的31例LVNC患者,列为LVNC组,另招募性别和年龄相匹配的10名健康志愿者(均为LVNC患者家属)为健康对照组。采用磁共振3.0扫描,胸前置32通道线圈。采用心脏电影成像(CINE)、MOLLI序列以获得左心室射血分数(LVEF)和Native T1值,并检测外周血MMP-9 mRNA及蛋白水平。结果:与健康对照组相比,LVNC组致密层心肌Native T1值较高(1096.0±41.5)ms vs.(1159.0±47.4)ms,P<0.001]。LVNC组患者的MMP-9 mRNA表达水平高于健康对照组(19.59±17.76 vs.1.76±0.72,P=0.003)。LVNC组的MMP-9蛋白水平也高于健康对照组(92.44±62.26)ng/ml vs.(58.32±28.19)ng/ml,P=0.025]。Spearman分析显示,Native T1值与MMP-9蛋白水平呈正相关(r=0.40,P=0.044)。结论:LVNC患者致密层心肌Native T1值显著增高,且与血清中MMP-9的表达有较高的一致性。

Correlation Between Compacted Layer Native T1 Value and Matrix Metalloproteinase-9 in Patients With Left Ventricular Non-compaction

Objectives:To investigate the relationships between compacted layer Native T1 mapping and matrix metalloproteinase-9 in patients with left ventricular non-compaction(LVNC).Methods:31 patients,who were hospitalized in our hospital and diagnosed as LVNC between December 2008 and June 2014,and 10 age and gender matched healthy volunteers were included and scanned by 3.0 T MR using a 32-channel phased array heart coil.Cine and MOLLI sequences were performed to acquire CINE images and Native T1 mapping.The serum protein and mRNA expression of MMP-9 was evaluated by ELISA and RT-PCR.Results:The mean Native T1 value of normal controls and LVNC patients was(1096.0±41.5)ms and(1159.0±47.4)ms(P<0.001)respectively.The mean mRNA of MMP-9 significantly higher in LVNC patients than in normal controls(19.59±17.76 vs.1.76±0.72,P=0.003),and MMP-9 proteins were also significantly higher in LVNC patients than in normal controls(92.44±62.26]ng/ml vs.58.32±28.19]ng/ml,P=0.025).Significant positive correlations were found between Native T1 value and MMP-9 protein concentration(r=0.40,P=0.044).Conclusions:The value of Native T1 mapping is significantly higher in compacted myocardium in LVNC patients,which is positively correlated with protein expression of MMP-9 in serum.