CMR-FT技术评估肺高血压患者早期右心室功能障碍

Assessment of early right ventricular dysfunction in pulmonary hypertension patients using cardiovascular magnetic resonance feature tracking technique

目的:采用心脏磁共振特征追踪(CMR-FT)技术定量评估肺高血压(PH)患者右心室心肌应变,探究其早期检测右心室功能障碍的价值。方法:回顾性收集确诊PH患者40例,健康成年人15例,均行CMR检查,根据右心室射血分数(RVEF)是否减低(<45%)将PH患者分成RVEF保留组(pRVEF PH组)和减低组(rRVEF PH组)。测量右心室心功能参数和心肌应变参数。结果:最终纳入pRVEF PH组14例、rRVEF PH组17例及对照组15例。与对照组相比,pRVEF PH组心功能参数均无显著变化,而整体纵向应变(GLS)显著减低(P=0.005);rRVEF PH组心功能及心肌应变参数均有显著变化(P均<0.05)。整体径向应变(GRS)、整体周向应变(GCS)、GLS与RVEF、右心室舒张末期容积指数(RVEDVI)、肺血管阻力(PVR)均有相关性(P均<0.05)。分别对pRVEF PH组和对照组、pRVEF和rRVEF PH组的整体应变指标进行受试者操作特征(ROC)曲线分析,结果示当RVEF无明显减低时,GLS>-22.12%可以预测PH患者右心室功能受损,ROC曲线下面积(AUC)为0.80;GRS、GCS、GLS均对rRVEF PH患者具有良好的预测价值,其中GLS预测效能最佳(临界值为-16.62%,AUC为0.966)。结论:右心室心肌应变可反映PH恶化进展情况,GLS有潜力成为早期检测PH患者右心室功能障碍的参考指标。

Objective:To quantitatively assess the myocardial strain of the right ventricle(RV) in pulmonary hypertension(PH) patients via cardiac magnetic resonance feature tracking(CMR-FT),and investigate its predictive value in detecting early RV dysfunction.Methods:40 PH patients and 15 healthy controls who all underwent CMR were retrospectively enrolled.According to whether the right ventricular ejection fraction(RVEF) was reduced(<45%),PH patients were divided into preserved-RVEF(pRVEF PH) group and reduced-RVEF(rRVEF PH) group.The RV functional parameters and myocardial strain parameters were measured.Results:A total of 14 pRVEF PH patients, 17 rRVEF PH patients, and 15 controls were finally included.Compared with the controls, there was no significant difference in RV function parameters, but the global longitudinal peak strain(GLS) was significantly decreased(P=0.005) in the pRVEF PH group.Both RV function parameters and myocardial strain were significantly changed in the rRVEF PH group compared with the controls(all P<0.05).Global radial peak strain(GRS),global circumferential peak strain(GCS) and GLS were correlated with RVEF,right ventricular end-diastolic volume index(RVEDVI) and pulmonary vascular resistance(PVR)(all P<0.05).Receiver operating characteristic(ROC) curve analysis was performed for the global strain parameters between the pRVEF PH group and control group, pRVEF and rRVEF PH groups, respectively.The cut-off value of GLS>-22.12% could detect impaired RV function in PH patients with pRVEF,the area under the curve(AUC) was 0.80.GRS,GCS,and GLS were predictors for PH patients with rRVEF,while GLS showed the best performance(cut-off value=-16.62%,AUC=0.966).Conclusion:RV myocardial strain was feasible to reflect the progression of PH patients.GLS has the potential to be the predictor for early detection of RV dysfunction in PH patients.