Meloni Antonella, Pepe Alessia, Positano Vincenzo, Favilli Brunella, Maggio Aurelio, Capra Marcello, Lo Pinto Carmela, Gerardi Calogera, Santarelli Maria Filomena, Midiri Massimo, Landini Luigi, Lombardi Massimo
MRI Laboratory, Institute of Clinical Physiology, G. Monasterio Foundation, Pisa, Italy.
J Magn Reson Imaging. 2009 Apr;29(4):832-7. doi: 10.1002/jmri.21704.
To determine whether T2* measurements quantifying myocardial iron overload in thalassemia patients are influenced by myocardial fibrosis and blood oxygenation.
Multislice multiecho T2* was performed in 94 thalassemia patients in order to quantify myocardial iron overload. The left ventricle was automatically segmented into a 16-segment standardized heart model, and the T2* value on each segment as well as the global T2* were calculated. Delayed enhanced cardiovascular magnetic resonance (DE-CMR) images were obtained to detect myocardial fibrosis. The blood oxygenation was assessed by the noninvasive measurement of partial pressure of oxygen (pO2).
Myocardial fibrosis was detected in 31 patients (33%). The global T2* value in patients with fibrosis was comparable with that of patients without fibrosis (P = 0.88) and T2* values in segments with fibrosis were comparable with those in segments without fibrosis (P = 0.83). The global T2* value was not correlated with the pO2 (Spearman's coefficient of correlation = 0.99).
Myocardial fibrosis and blood oxygenation did not significantly affect the T2* values. These data further support the use of heart T2* as equivalent of heart iron in the clinical arena.
确定用于量化地中海贫血患者心肌铁过载的T2*测量是否受心肌纤维化和血液氧合的影响。
对94例地中海贫血患者进行多层多回波T2检查，以量化心肌铁过载。左心室自动分割为16节段标准化心脏模型，计算各节段的T2值以及整体T2*值。获取延迟强化心血管磁共振（DE-CMR）图像以检测心肌纤维化。通过无创测量氧分压（pO2）评估血液氧合情况。
31例患者（33%）检测到心肌纤维化。有纤维化患者的整体T2值与无纤维化患者相当（P = 0.88），有纤维化节段的T2值与无纤维化节段相当（P = 0.83）。整体T2*值与pO2无相关性（Spearman相关系数 = 0.99）。
心肌纤维化和血液氧合对T2值无显著影响。这些数据进一步支持在临床领域将心脏T2等同于心脏铁的应用。
