Kuruvilla Sujith, Janardhanan Rajesh, Antkowiak Patrick, Keeley Ellen C, Adenaw Nebiyu, Brooks Jeremy, Epstein Frederick H, Kramer Christopher M, Salerno Michael
Department of Medicine (Cardiology), Cardiovascular Imaging Center, University of Virginia Health System, Charlottesville, Virginia.
Department of Radiology, Cardiovascular Imaging Center, University of Virginia Health System, Charlottesville, Virginia.
JACC Cardiovasc Imaging. 2015 Feb;8(2):172-80. doi: 10.1016/j.jcmg.2014.09.020. Epub 2015 Jan 7.
The goal of this study was to assess the relationship among extracellular volume (ECV), native T1, and systolic strain in hypertensive patients with left ventricular hypertrophy (HTN LVH), hypertensive patients without LVH (HTN non-LVH), and normotensive controls.
Diffuse myocardial fibrosis in HTN LVH patients, as reflected by increased ECV and native T1, may be an underlying mechanism contributing to increased cardiovascular risk compared with HTN non-LVH subjects and controls. Furthermore, increased diffuse fibrosis in HTN LVH subjects may be associated with reduced peak systolic and early diastolic strain rate compared with the other 2 groups.
T1 mapping was performed in 20 HTN LVH (mean age, 55 ± 11 years), 23 HTN non-LVH (mean age, 61 ± 12 years), and 22 control subjects (mean age, 54 ± 7 years) on a Siemens 1.5-T Avanto (Siemens Healthcare, Erlangen, Germany) using a previously validated modified look-locker inversion-recovery pulse sequence. T1 was measured pre-contrast and 10, 15, and 20 min after injection of 0.15 mmol/kg gadopentetate dimeglumine, and the mean ECV and native T1 were determined for each subject. Measurement of circumferential strain parameters were performed using cine displacement encoding with stimulated echoes.
HTN LVH subjects had higher native T1 compared with controls (p < 0.05). HTN LVH subjects had higher ECV compared with HTN non-LVH subjects and controls (p < 0.05). Peak systolic circumferential strain and early diastolic strain rates were reduced in HTN LVH subjects compared with HTN non-LVH subjects and controls (p < 0.05). Increased levels of ECV and native T1 were associated with reduced peak systolic and early diastolic circumferential strain rate across all subjects.
HTN LVH patients had higher ECV, longer native T1 and associated reduction in peak systolic circumferential strain, and early diastolic strain rate compared with HTN non-LVH and control subjects. Measurement of ECV and native T1 provide a noninvasive assessment of diffuse fibrosis in hypertensive heart disease.
本研究旨在评估左心室肥厚的高血压患者（HTN LVH）、无左心室肥厚的高血压患者（HTN非LVH）和血压正常的对照组之间细胞外容积（ECV）、固有T1和收缩期应变的关系。
HTN LVH患者的弥漫性心肌纤维化表现为ECV和固有T1增加，这可能是与HTN非LVH受试者和对照组相比心血管风险增加的潜在机制。此外，与其他两组相比，HTN LVH受试者中弥漫性纤维化增加可能与收缩期峰值和舒张早期应变率降低有关。
在西门子1.5-T Avanto（德国埃尔兰根西门子医疗公司）上，使用先前验证的改良Look-Locker反转恢复脉冲序列，对20例HTN LVH患者（平均年龄55±11岁）、23例HTN非LVH患者（平均年龄61±12岁）和22例对照受试者（平均年龄54±7岁）进行T1 mapping。在注射0.15 mmol/kg钆喷酸葡胺前及注射后10、15和20分钟测量T1，并为每个受试者确定平均ECV和固有T1。使用cine位移编码和受激回波进行圆周应变参数测量。
与对照组相比，HTN LVH受试者的固有T1更高（p<0.05）。与HTN非LVH受试者和对照组相比，HTN LVH受试者的ECV更高（p<0.05）。与HTN非LVH受试者和对照组相比，HTN LVH受试者的收缩期峰值圆周应变和舒张早期应变率降低（p<0.05）。在所有受试者中，ECV和固有T1水平升高与收缩期峰值和舒张早期圆周应变率降低有关。
与HTN非LVH和对照受试者相比，HTN LVH患者的ECV更高，固有T1更长，收缩期峰值圆周应变和舒张早期应变率降低。测量ECV和固有T1可对高血压性心脏病中的弥漫性纤维化进行无创评估。
