Myocardial Scar Delineation Using Diffusion Tensor Magnetic Resonance Tractography.
Myocardial Scar Delineation Using Diffusion Tensor Magnetic Resonance Tractography.
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DOI：
10.1161/jaha.117.007834
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发表时间：
2018-02-02
影响因子：
5.4
通讯作者：
Sosnovik DE
中科院分区：
文献类型：
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作者：
Mekkaoui C;Jackowski MP;Kostis WJ;Stoeck CT;Thiagalingam A;Reese TG;Reddy VY;Ruskin JN;Kozerke S;Sosnovik DE
晚期钆增强（LGE）是心肌疤痕勾画的当前标准。在本研究中，我们介绍了纤维束描记传播角 (PA)，这是一种源自扩散张量成像 (DTI) 的肌纤维曲率（度/单位距离）度量，并将其与 LGE 和心内膜电压映射侵入性疤痕评估的使用进行比较。 对 7 名健康人类志愿者、5 名心肌梗塞患者、6 只正常小鼠和 7 只心肌梗塞小鼠进行了 DTI。使用二维反转恢复梯度回波序列进行 LGE 来描绘梗塞和边界区域。对 5 个正常人和 5 个正常绵羊心脏进行离体 DTI。对 5 只梗塞绵羊心脏进行心内膜电解剖测绘和随后的离体 DTI。正常人心脏的PA变化平稳，一般<4。梗死区的平均PA显着升高（10.34±1.02 vs 4.05±0.45，P<0.05）。 PA ≤ 4 的区域的双极电压始终≥1.5 mV，而 PA 值在 4 到 10 之间的区域的双极电压在 0.5 到 1.5 mV 之间。 PA 阈值 >4 是 DTI 衍生的梗塞面积最准确的测量值，并且与 LGE 的相关性最大（r=0.95）。我们发现小鼠和人类的 PA 和 LGE 梗塞面积之间存在很强的相关性。 PA 值与心内膜电压之间也存在反比关系。 PA 的使用可以在不需要外源性造影剂的情况下勾画心肌疤痕并表征致心律失常基质。
Late gadolinium enhancement (LGE) is the current standard for myocardial scar delineation. In this study, we introduce the tractographic propagation angle (PA), a metric of myofiber curvature (degrees/unit distance) derived from diffusion tensor imaging (DTI), and compare its use to LGE and invasive scar assessment by endocardial voltage mapping. DTI was performed on 7 healthy human volunteers, 5 patients with myocardial infarction, 6 normal mice, and 7 mice with myocardial infarction. LGE to delineate the infarct and border zones was performed with a 2‐dimensional inversion recovery gradient‐echo sequence. Ex vivo DTI was performed on 5 normal human and 5 normal sheep hearts. Endocardial electroanatomic mapping and subsequent ex vivo DTI was performed on 5 infarcted sheep hearts. PA in the normal human hearts varied smoothly and was generally <4. The mean PA in the infarct zone was significantly elevated (10.34±1.02 versus 4.05±0.45, P<0.05). Regions with a PA ≤4 consistently had a bipolar voltage ≥1.5 mV, whereas those with PA values between 4 and 10 had voltages between 0.5 and 1.5 mV. A PA threshold >4 was the most accurate DTI‐derived measure of infarct size and demonstrated the greatest correlation with LGE (r=0.95). We found a strong correlation between infarct size by PA and LGE in both mice and humans. There was also an inverse relationship between PA values and endocardial voltage. The use of PA may enable myocardial scar delineation and characterization of arrhythmogenic substrate without the need for exogenous contrast agents.