Garg Pankaj, Broadbent David A, Swoboda Peter P, Foley James R J, Fent Graham J, Musa Tarique A, Ripley David P, Erhayiem Bara, Dobson Laura E, McDiarmid Adam K, Haaf Philip, Kidambi Ananth, van der Geest Rob J, Greenwood John P, Plein Sven
From the Division of Biomedical Imaging, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, United Kingdom (P.G., D.A.B., P.P.S., J.R.J.F., G.J.F., T.A.M., D.P.R., B.E., L.E.D., A.K.M., P.H., A.K., J.P.G., S.P.); Medical Physics and Engineering, Leeds Teaching Hospitals NHS Trust, United Kingdom (D.A.B.); and Division of Image Processing, Leiden University Medical Centre, The Netherlands (R.J.v.d.G.).
Circ Cardiovasc Imaging. 2017 Jul;10(7). doi: 10.1161/CIRCIMAGING.117.006182.
Late gadolinium enhancement (LGE) imaging overestimates acute infarct size. The main aim of this study was to investigate whether acute extracellular volume (ECV) maps can reliably quantify myocardial area at risk (AAR) and final infarct size (IS).
Fifty patients underwent cardiovascular magnetic resonance imaging acutely (24-72 hours) and at convalescence (3 months). The cardiovascular magnetic resonance protocol included cines, T2-weighted imaging, native T1 maps, 15-minute post-contrast T1 maps, and LGE. Optimal AAR and IS ECV thresholds were derived in a validation group of 10 cases (160 segments). Eight hundred segments (16 per patient) were analyzed to quantify AAR/IS by ECV maps (ECV thresholds for AAR is 33% and IS is 46%), T2-weighted imaging, T1 maps, and acute LGE. Follow-up LGE imaging was used as the reference standard for final IS and viability assessment. The AAR derived from ECV maps (threshold of >33) demonstrated good agreement with T2-weighted imaging-derived AAR (bias, 0.18; 95% confidence interval [CI], -1.6 to 1.3) and AAR derived from native T1 maps (bias=1; 95% CI, -0.37 to 2.4). ECV demonstrated the best linear correlation to final IS at a threshold of >46% (=0.96; 95% CI, 0.92-0.98; <0.0001). ECV maps demonstrated better agreement with final IS than acute IS on LGE (ECV maps: bias, 1.9; 95% CI, 0.4-3.4 versus LGE imaging: bias, 10; 95% CI, 7.7-12.4). On multiple variable regression analysis, the number of nonviable segments was independently associated with IS by ECV maps (β=0.86; <0.0001).
ECV maps can reliably quantify AAR and final IS in reperfused acute myocardial infarction. Acute ECV maps were superior to acute LGE in terms of agreement with final IS. IS quantified by ECV maps are independently associated with viability at follow-up.
延迟钆增强（LGE）成像高估了急性梗死面积。本研究的主要目的是调查急性细胞外容积（ECV）图能否可靠地量化心肌梗死危险区（AAR）和最终梗死面积（IS）。
50例患者在急性发病期（24 - 72小时）和恢复期（3个月）接受了心血管磁共振成像检查。心血管磁共振成像方案包括电影成像、T2加权成像、原生T1图、造影剂注射后15分钟T1图和LGE。在10例患者（160个节段）的验证组中得出最佳AAR和IS的ECV阈值。对800个节段（每位患者16个）进行分析，通过ECV图（AAR的ECV阈值为33%，IS的ECV阈值为46%）、T2加权成像、T1图和急性LGE来量化AAR/IS。随访LGE成像用作最终IS和存活心肌评估的参考标准。由ECV图得出的AAR（阈值>33）与T2加权成像得出的AAR（偏差，0.18；95%置信区间[CI]，-1.6至1.3）以及原生T1图得出的AAR（偏差 = 1；95% CI，-0.37至2.4）显示出良好的一致性。在阈值 > 46%时，ECV与最终IS的线性相关性最佳（= 0.96；95% CI，0.92 - 0.98；< 0.0001）。与LGE上的急性IS相比，ECV图与最终IS的一致性更好（ECV图：偏差，1.9；95% CI，0.4 - 3.4；而LGE成像：偏差，10；95% CI，7.7 - 12.4）。在多变量回归分析中，无存活节段的数量通过ECV图与IS独立相关（β = 0.86；< 0.0001）。
ECV图能够可靠地量化再灌注急性心肌梗死中的AAR和最终IS。在与最终IS的一致性方面，急性ECV图优于急性LGE。通过ECV图量化的IS与随访时的存活心肌独立相关。
