Lanjewar Charan, Ephrem Biju, Mishra Nidhish, Jhankariya Bhaven, Kerkar Prafulla
Department of Cardiology, King Edward VII Memorial Hospital, Acharya Donde Marg, Parel, Mumbai, India.
J Heart Valve Dis. 2010 May;19(3):357-63.
To date, no investigations have been made on the role of magnetic resonance imaging (MRI) in evaluating mitral stenosis (MS) in Asian countries such as India, where rheumatic MS is more common. An accurate assessment of the mitral valve area (MVA) is particularly important when managing patients with valvular stenosis. Current standard techniques to assess the severity of MS include echocardiography and cardiac catheterization, the former of which represents the most practical approach. The study aim was to evaluate the accuracy and clinical utility of planimetry of the MVA and peak gradient, assessed by MRI in comparison with echocardiography, in rheumatic heart disease (RHD) patients with MS.
Among a group of 30 patients with suspected or known MS, planimetry of the MVA and mitral valve gradient (MVG) was performed with a 1.5 Tesla MRI scanner, using a breath-hold balanced gradient echo sequence (true FISP) and velocity-encoded MRI, respectively. The data obtained were compared with the echocardiographically determined MVA (ECHO-MVA).
The correlation between the MRI-MVA and ECHO-MVA was 0.81 (p < 0.0001), and between the MRI-MVG and ECHO-MVG was 0.81 (p < 0.0001). The MRI-MVA slightly overestimated the ECHO-MVA by 8.1% (1.61 +/- 0.42 cm2 versus 1.48 +/- 0.42 cm2; p < 0.05).
To the present authors' knowledge, this study is the first in which MRI has been used to evaluate MVA by planimetry, particularly in RHD. MRI is capable of adequately evaluating patients with rheumatic MS with respect to the peak gradient and MVA by planimetry. Thus, MRI planimetry of the mitral valve orifice in MS offers a reliable and safe method for the quantification of MS. Further studies are required to standardize the procedure in those patients with atrial fibrillation, or who are more symptomatic.
迄今为止，在印度等亚洲国家，风湿性二尖瓣狭窄（MS）更为常见，但尚未有关于磁共振成像（MRI）在评估二尖瓣狭窄中的作用的研究。在管理瓣膜狭窄患者时，准确评估二尖瓣瓣口面积（MVA）尤为重要。目前评估MS严重程度的标准技术包括超声心动图和心导管检查，其中前者是最实用的方法。本研究的目的是评估在风湿性心脏病（RHD）合并MS的患者中，通过MRI测量MVA和峰值梯度，并与超声心动图进行比较，以评估其准确性和临床实用性。
在一组30例疑似或已知MS的患者中，分别使用1.5特斯拉MRI扫描仪，采用屏气平衡梯度回波序列（真稳态进动快速成像）和速度编码MRI进行MVA和二尖瓣瓣口梯度（MVG）的平面测量。将获得的数据与超声心动图测定的MVA（ECHO-MVA）进行比较。
MRI-MVA与ECHO-MVA之间的相关性为0.81（p < 0.0001），MRI-MVG与ECHO-MVG之间的相关性为0.81（p < 0.0001）。MRI-MVA比ECHO-MVA略有高估，高估了8.1%（1.61±0.42 cm²对1.48±0.42 cm²；p < 0.05）。
据作者所知，本研究是首次使用MRI通过平面测量来评估MVA，尤其是在RHD患者中。MRI能够通过平面测量充分评估风湿性MS患者的峰值梯度和MVA。因此，MRI对MS二尖瓣口的平面测量为MS的量化提供了一种可靠且安全的方法。对于房颤患者或症状更明显的患者，需要进一步研究以规范该检查程序。
