Department of Clinical Physiology, Lund University, Lund University Hospital, Lund, Sweden.
BMC Cardiovasc Disord. 2013 Dec 5;13:110. doi: 10.1186/1471-2261-13-110.
Cardiovascular-MR (CMR) is the gold standard for quantifying myocardial infarction using late gadolinium enhancement (LGE) technique. Both 2D- and 3D-LGE-sequences are used in clinical practise and in clinical and experimental studies for infarct quantification. Therefore the aim of this study was to investigate if image acquisitions with 2D- and 3D-LGE show the same infarct size in patients and ex vivo.
Twenty-six patients with previous myocardial infarction who underwent a CMR scan were included. Images were acquired 10-20 minutes after an injection of 0.2 mmol/kg gadolinium-based contrast agent. Two LGE-sequences, 3D-inversion recovery (IR) and 2D-phase-sensitive (PS) IR, were used in all patients to quantify infarction size. Furthermore, six pigs with reperfused infarction in the left anterior descending artery (40 minutes occlusion and 4 hours of reperfusion) were scanned with 2D- and 3D-LGE ex vivo. A high resolution T1-sequence was used as reference for the infarct quantification ex vivo. Spearman's rank-order correlation, Wilcoxon matched pairs test and bias according to Bland-Altman was used for comparison of infarct size with different LGE-sequences.
There was no significant difference between the 2D- and 3D-LGE sequence in left ventricular mass (LVM) (2D: 115 ± 25 g; 3D: 117 ± 24 g: p = 0.35). Infarct size in vivo using 2D- and 3D-LGE showed high correlation and low bias for both LGE-sequences both in absolute volume of infarct (r = 0.97, bias 0.47 ± 2.1 ml) and infarct size as part of LVM (r = 0.94, bias 0.16 ± 2.0%). The 2D- and 3D-LGE-sequences ex vivo correlated well (r = 0.93, bias 0.67 ± 2.4%) for infarct size as part of the LVM. The IR LGE-sequences overestimated infarct size as part of the LVM ex vivo compared to the high resolution T1-sequence (bias 6.7 ± 3.0%, 7.3 ± 2.7% for 2D-PSIR and 3D-IR respectively, p < 0.05 for both).
Infarct quantification with 2D- and 3D-LGE gives similar results in vivo with a very low bias. IR LGE-sequences optimized for in vivo use yield an overestimation of infarct size when used ex vivo.
心血管磁共振（CMR）是使用晚期钆增强（LGE）技术量化心肌梗死的金标准。2D 和 3D-LGE 序列在临床实践以及临床和实验研究中都用于梗死量化。因此，本研究的目的是研究 2D 和 3D-LGE 图像采集在患者和离体中是否显示相同的梗死大小。
纳入 26 例既往心肌梗死患者，行 CMR 扫描。在注射 0.2mmol/kg 钆基造影剂后 10-20 分钟采集图像。所有患者均使用 3D 反转恢复（IR）和 2D 相位敏感（PS）IR 两种 LGE 序列进行量化。此外，对六只经左前降支再灌注的猪进行离体 2D 和 3D-LGE 扫描（闭塞 40 分钟，再灌注 4 小时）。高分辨率 T1 序列用于离体梗死量化的参考。使用 Spearman 秩相关、Wilcoxon 配对检验和 Bland-Altman 偏倚比较不同 LGE 序列的梗死大小。
2D 和 3D-LGE 序列在左心室质量（LVM）方面无显著差异（2D：115±25g；3D：117±24g：p=0.35）。在体 2D 和 3D-LGE 序列的梗死大小具有高度相关性和低偏倚，两种 LGE 序列的梗死体积绝对值（r=0.97，偏倚 0.47±2.1ml）和梗死体积占 LVM 的比例（r=0.94，偏倚 0.16±2.0%）均如此。离体 2D 和 3D-LGE 序列的梗死体积相关性良好（r=0.93，偏倚 0.67±2.4%），占 LVM 的比例相同。与高分辨率 T1 序列相比，IR LGE 序列体外测量 LVM 部分的梗死大小存在高估（2D-PSIR 和 3D-IR 的偏倚分别为 6.7±3.0%和 7.3±2.7%，两者均 p<0.05）。
2D 和 3D-LGE 的梗死量化在体内具有非常低的偏倚，结果相似。用于体内使用的优化 IR LGE 序列在体外使用时会高估梗死大小。
