Liu Chia-Ying, Noda Chikara, Ambale-Venkatesh Bharath, Kato Yoko, Kassai Yoshimori, Bluemke David A, Balasubramanian Aparna, Lima João A C
Canon Medical Systems Corporation, 1385 Shimoishigami, Otawara-shi, 324-8550, Tochigi, Japan.
Division of Cardiology, Johns Hopkins University, Baltimore, MD, USA.
Int J Cardiovasc Imaging. 2025 Aug 12. doi: 10.1007/s10554-025-03479-7.
While the normal ranges of myocardial T1 and T2 have been vastly reported, the studies on blood T2 are limited and data is sparse. The purpose of this study was to report the age and sex distribution of right (RV) and left ventricular (LV) blood T2 in the human heart and to evaluate their relationships to lung volume. 156 asymptomatic adults without hypertension or diabetes and free from cardiopulmonary disease (74 men, mean age 50 ± 14 years, range 24-81 years) were included. 3T MRI including cardiac scout and T2-prepared gradient-echo sequence for T2 mapping were acquired with breath hold in the resting lung position (i.e. functional residual capacity, FRC). T2 maps were used to measure blood T2 times. MRI-estimated FRC (MRI-eFRC) was measured using a single scout image in the coronal orientation and was assessed by delineation of the chest wall manually excluding the heart. Men had higher MRI-eFRC (p = 0.002) and LV blood T2 (99 ± 24 ms vs. 91 ± 21 ms, p = 0.03) than women but RV blood T2 were similar (81 ± 12 ms vs. 78 ± 11 ms, p = 0.2). Both MRI-eFRC (r = 0.17, p = 0.04) and LV blood T2 (r = 0.33, p < 0.0001) were positively correlated with age, while RV blood T2 did not show age dependence. MRI-eFRC was also positively correlated with LV blood T2 (r = 0.18, p = 0.02) but not with RV blood T2. Ventricular T2 values exhibited good intra- and inter-observer reproducibility (coefficient of variation < 3%). Our study provides the normal ranges of ventricular blood T2 relaxation times in sex and age groups using the T2-prepared gradient echo sequence at 3T and demonstrated that LV blood T2 is positively associated with age, which may serve as a basis for future studies for clinical CMR examination involving patients with diseases altering these parameters.
虽然已有大量关于心肌T1和T2正常范围的报道，但关于血液T2的研究有限且数据稀少。本研究的目的是报告人体心脏右心室（RV）和左心室（LV）血液T2的年龄和性别分布，并评估它们与肺容积的关系。纳入了156名无高血压或糖尿病且无心肺疾病的无症状成年人（74名男性，平均年龄50±14岁，范围24 - 81岁）。采用3T磁共振成像（MRI），包括心脏定位像和用于T2 mapping的T2准备梯度回波序列，在静息肺位（即功能残气量，FRC）屏气状态下采集图像。T2图谱用于测量血液T2时间。MRI估计的FRC（MRI - eFRC）通过在冠状位的单个定位像测量，并通过手动勾勒胸壁（不包括心脏）进行评估。男性的MRI - eFRC（p = 0.002）和LV血液T2（99±24 ms对91±21 ms，p = 0.03）高于女性，但RV血液T2相似（81±12 ms对78±11 ms，p = 0.2）。MRI - eFRC（r = 0.17，p = 0.04）和LV血液T2（r = 0.33，p < 0.0001）均与年龄呈正相关，而RV血液T2未显示出年龄依赖性。MRI - eFRC也与LV血液T2呈正相关（r = 0.18，p = 0.02），但与RV血液T2无相关性。心室T2值在观察者内和观察者间均表现出良好的可重复性（变异系数<3%）。我们的研究提供了使用3T的T2准备梯度回波序列在不同性别和年龄组中心室血液T2弛豫时间的正常范围，并表明LV血液T2与年龄呈正相关，这可为未来涉及改变这些参数的疾病患者的临床CMR检查研究提供基础。
