Hakacova Nina, Robinson Anna M C, Maynard Charles, Wagner Galen S, Idriss Salim F
Duke University Medical Center, Durham, NC, USA.
Clin Physiol Funct Imaging. 2009 May;29(3):181-6. doi: 10.1111/j.1475-097X.2008.00853.x. Epub 2009 Jan 15.
Determination of mitral papillary muscle positions is of increasing interest in wide spectrum of clinical cardiology fields. Particularly, relative positioning of the papillary muscles between the inter-ventricular septum and the left ventricular free wall is of interest. A reproducible method for determination of papillary muscle positions has not been established. In this study a new 'septal-to-free wall arc ratio' (SFAR) method for measuring papillary muscle positions is presented. The reproducibility of the SFAR method between echocardiographic (ECHO) and magnetic resonance (MRI) modalities and between observers is tested.
Twenty subjects with structurally normal hearts in whom both MRI and ECHO were performed in 2007 were included in the study. Papillary muscle positions were determined using the SFAR method. Inter-modality (ECHO and MRI) and inter-observer reproducibility of the methods was assessed by calculating correlation coefficients and the mean difference from agreement.
The inter-modality correlation of the SFAR method was 0.80 (P < 0.0001) for both papillary muscles. The mean difference of measurements from agreement was 4% for the superior and 2% for the inferior papillary muscle. The inter-observer correlation was 0.93 (P < 0.0001) for superior and 0.90 (P = 0.0002) for inferior papillary muscle. The mean inter-observer difference from agreement was 2% for superior and 3% for inferior papillary muscle.
The SFAR method may be applied in wide range of both scientific and clinical medical fields as a reproducible method for determination of papillary muscle positions with the benefit of estimation of relative papillary muscle positions both from the septum and the free wall.
二尖瓣乳头肌位置的确定在广泛的临床心脏病学领域中越来越受到关注。特别是，乳头肌在室间隔和左心室游离壁之间的相对位置备受关注。尚未建立一种可重复的确定乳头肌位置的方法。在本研究中，提出了一种新的测量乳头肌位置的“间隔至游离壁弧比”（SFAR）方法。测试了SFAR方法在超声心动图（ECHO）和磁共振成像（MRI）模式之间以及观察者之间的可重复性。
本研究纳入了20名在2007年同时进行了MRI和ECHO检查且心脏结构正常的受试者。使用SFAR方法确定乳头肌位置。通过计算相关系数和一致性的平均差异来评估该方法在不同模式（ECHO和MRI）之间以及观察者之间的可重复性。
对于两个乳头肌，SFAR方法在不同模式之间的相关性均为0.80（P < 0.0001）。测量值与一致性的平均差异，上乳头肌为4%，下乳头肌为2%。上乳头肌观察者间的相关性为0.93（P < 0.0001），下乳头肌为0.90（P = 0.0002）。观察者间测量值与一致性的平均差异，上乳头肌为2%，下乳头肌为3%。
SFAR方法可作为一种可重复的确定乳头肌位置的方法应用于广泛的科学和临床医学领域，其优点是能够从间隔和游离壁两个方面估计乳头肌的相对位置。
