基于CT特征追踪技术量化左心室心肌应变参数在肥厚型梗阻性心肌病中的应用

Quantifying Left Ventricular Myocardial Strain Parameters via CT Feature Tracking: the Application in Hypertrophic Obstructive Cardiomyopathy

目的探讨基于CT特征追踪技术量化左心室心肌应变(MS)的可行性以及对肥厚型梗阻性心肌病(HOCM)患者的意义。资料与方法回顾性纳入2019年3月—2021年12月于空军军医大学第一附属医院行心脏冠状动脉CT血管成像检查的HOCM患者35例,并随机纳入疑似冠状动脉疾病就诊者中冠状动脉CT血管成像检查阴性者60例作为对照组。通过后处理软件分别量化受试者的常规心功能参数及MS参数,分析两组各参数的差异,并评估MS参数诊断HOCM的效能。结果与对照组相比,HOCM组常规左心室功能参数中左心室壁最大厚度、左心室质量、左心室质量指数、左心室射血分数、左心室舒张末期容积及每搏输出量显著增加,差异有统计学意义(t=2.119~24.861,P均<0.05);左心室收缩末期容积及心排血量差异无统计学意义(P>0.05)。MS参数中,HOCM组整体纵向及径向应变值显著减少(t=12.857、-6.427,P<0.01),而心内膜下整体周向应变值显著增加(t=-2.369,P<0.05)。MS参数中心肌整体纵向应变对HOCM的诊断效能最佳,曲线下面积为0.997。当心肌整体纵向绝对值≤20.78%时敏感度和特异度最高,分别为100%与95%。结论CT特征追踪技术量化的MS参数在定量分析左心室功能方面优于左心室射血分数,其中纵向应变对早期心肌功能损伤的敏感度及特异度最高,并且该技术可重复性好,有望成为HOCM患者心肌功能评估的新指标。

Purpose To investigate the feasibility of CT-based feature tracking technology to quantify left ventricular myocardial strain(MS)and its significance in hypertrophic obstructive cardiomyopathy(HOCM).Materials and Methods A total of 35 HOCM patients who underwent cardiac coronary angiography from March 2019 to December 2021 in the First Affiliated Hospital of the Air Force Military Medical University were retrospectively included,and a total of 60 cases who were negative for cardiac coronary angiography among those who visited the hospital with suspected coronary artery disease were randomly enrolled.Conventional cardiac functional parameters and MS parameters were quantified via post-processing software,and differences of parameters between the groups were analyzed.The diagnostic efficacy of MS parameters for HOCM was further evaluated.Results Compared to the control group,the HOCM group exhibited significant increases in various conventional left ventricular functional parameters,including left ventricular wall thickness,mass,mass index,end-diastolic volume and stroke volume(t=2.119 to 24.861,all P<0.05).However,there were no statistically significant differences in end-systolic volume and cardiac output between the two groups(P>0.05).The global longitudinal and radial strain values of HOCM group were significantly lower than those of control group(t=12.857,-6.427,P<0.01),while the endocardial global circumferential strain of HOCM group was significantly higher than that of control group(t=-2.369,P<0.05).Among MS parameters,global longitudinal strain exhibited the best diagnostic efficacy for HOCM,with an area under the curve of 0.997.A cutoff value of≤20.78%for global longitudinal strain showed that the sensitivity and specificity was 100%and 95%,respectively.Conclusion The MS parameters quantified by the CT-based feature tracking technique are superior to left ventricular ejection fraction in quantifying left ventricular function,with the highest sensitivity and specificity for early myocardial function impairment of longitudinal strain.In addition,the technique has good repeatability and is expected to become a new indicator for the assessment of myocardial function in HOCM.