Cardiovascular Magnetic Resonance Visualization of Cardiac Amyloid Infiltration: Challenges and Opportunities.
Cardiovascular Magnetic Resonance Visualization of Cardiac Amyloid Infiltration: Challenges and Opportunities.
复制标题
心脏淀粉样蛋白浸润的心血管磁共振可视化：挑战和机遇。
DOI：
10.1161/circulationaha.115.018832
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发表时间：
2015
期刊：
影响因子：
37.8
通讯作者：
Nezafat,Reza
中科院分区：
文献类型：
--
作者：
Ruberg,FrederickL;Nezafat,Reza
(27%). CMR成像包括在所有患者中使用标准幅度反转恢复（MAG-IR）LGE成像和在43%的患者中使用PSIR LGE成像的造影前和造影后T1/ECV测定。然后，作者分析了LGE图像，并在一个简单的三方分类方案（正常，内膜下，透壁）中对LGE模式进行分类，同时将观察到的LGE模式与ECV和临床结局相关联。通过这种方式，他们能够比较标准MAG-IR与PSIR，AL与TTR，以及早期与晚期疾病。患者还通过超声心动图（尽管明显没有纵向收缩应变）和血清心脏生物标志物（包括N-末端脑钠肽前体（但不是肌钙蛋白））进行了表征。为了证实ATTR队列中的心脏淀粉样变性，作者报告了Tc 99 m-DPD（3，3-二膦酰基-1，2-丙二羧酸）放射成像的成像特征。本报告的主要结论如下。首先，通过LGE模式从正常进展到透壁，似乎存在淀粉样蛋白积累的连续性，后者在ATTR中更普遍，具有不特异于淀粉样蛋白类型的稳健ECV切割点。第二，在一个子集的100例患者的对比后T1地图作为“真理标准”的对比度积累在假定淀粉样蛋白沉积的地区，PSIR技术被证明上级传统的MAG-IR的准确性分配的LGE模式。MAG-IR和PSIR之间的不一致性很高（57%），考虑到该已建立的淀粉样变性和经验丰富的CMR中心的专业知识，这是一个令人印象深刻的观察结果，而PSIR和造影后T1图并不不一致。第三，无论淀粉样蛋白类型如何，透壁LGE模式与死亡率独立相关，在校正超声心动图特征或N-末端脑钠肽前体后仍与死亡率相关（风险比，4.13; 95%置信区间，1.30-13.07; P< 0.0001）。第四，39%的无LGE和无心脏淀粉样变性临床表现的患者（通过CMR、超声心动图或N末端脑钠肽前体确定）的ECV测量值高于报告的正常范围（结果在0.32和0.40之间），这表明在这些其他方法的检测阈值之下非常早期的淀粉样蛋白积累。这项研究极大地告知了我们对淀粉样心肌病是如何从早期浸润发展到晚期浸润的，同时提供了对LGE及其与生存关系的相互矛盾的先前报道的见解。一个与先前报告一致的重要观察结果是，在透壁LGE患者中，与最高ECV和最差预后相关，心肌比血池保留更多的钆，导致血池信号无效并使心肌均匀明亮（称为弥漫性增强）。7同样值得注意的是，LGE模式预测生存率与淀粉样变性类型无关，尽管这在AL中表现得最明显。考虑到PSIR与MAG-IR的高度不一致性，PSIR与造影后T1图的高度一致性，以及PSIR的相对简单性和广泛可用性，作者得出结论，PSIR应取代MAG-IR作为心脏淀粉样变性的LGE方法的选择。重要的是要注意，用于评估T1图、PSIR和MAG-IR LGE之间不一致性的方法是
(27%). CMR imaging involved precontrast and postcontrast T1/ECV determination with standard magnitude inversion recovery (MAG-IR) LGE imaging in all patients and PSIR LGE imaging in 43% of patients. The authors then analyzed LGE images and categorized LGE pattern in a simple tripartite classification scheme (normal, subendocardial, transmural) while associating the observed LGE pattern with ECV and clinical outcomes. In this way, they were able to compare standard MAG-IR with PSIR, AL with TTR, and early with advanced disease. The patients were also characterized by echocardiography (although notably without longitudinal systolic strain) and serum cardiac biomarkers, including N-terminal pro-brain natriuretic peptide (but not troponin). To substantiate cardiac amyloidosis in the ATTR cohort, the authors reported imaging characteristics with Tc99m-DPD (3, 3-diphosphono-1, 2-propanodicarboxylicacid) scintigraphy. The principal findings of this report are as follows. First, there appeared to be a continuum of amyloid accumulation as determined by LGE pattern progressing from normal to transmural, the latter being more prevalent in ATTR, with robust ECV cut points that were not specific to amyloid type. Second, in a subset of 100 patients with postcontrast T1 maps as the “truth standard” for contrast accumulation in areas of presumptive amyloid deposition, the PSIR technique proved superior to conventional MAG-IR for accuracy in assignment of LGE pattern. Discordance between MAG-IR and PSIR was high (57%), an impressive observation given the expertise of this established amyloidosis and experienced CMR center, whereas PSIR and postcontrast T1 maps were not discordant. Third, a transmural LGE pattern was independently associated with mortality regardless of amyloid type and remained associated after adjustment for echocardiographic characteristics or N-terminal pro-brain natriuretic peptide (hazard ratio, 4.13; 95% confidence interval, 1.30–13.07; P< 0.0001). Fourth and finally, 39% of patients with no LGE and no clinical manifestations of cardiac amyloidosis, as determined by CMR, echocardiography, or N-terminal pro-brain natriuretic peptide, had ECV measurements above the reported normal range (with results between 0.32 and 0.40), suggesting very early amyloid accumulation beneath the detection threshold of these other approaches.This study greatly informs our understanding of how amyloid cardiomyopathy progresses from early to advanced stage of infiltration while providing insight into conflicting prior reports of LGE and its relationship to survival. One important observation consistent with prior reports is that, among patients with transmural LGE, associated with the highest ECV and worst prognosis, myocardium retained more gadolinium than the blood pool, causing blood pool signal nulling and rendering the myocardium uniformly bright (called diffuse hyperenhancement). 7 It is also notable that LGE pattern predicted survival regardless of amyloidosis type, although this appeared most striking in AL. Given this high discordance of PSIR from MAG-IR, the high concordance of PSIR with postcontrast T1 maps, and comparative simplicity and widespread availability of PSIR, the authors concluded that PSIR should replace MAG-IR as the LGE method of choice in cardiac amyloidosis. It is important to note that the methodology used to assess discordance between T1 maps, PSIR, and MAG-IR LGE was