Magnetic resonance imaging with 3-dimensional analysis of left ventricular remodeling in isolated mitral regurgitation: implications beyond dimensions.
Magnetic resonance imaging with 3-dimensional analysis of left ventricular remodeling in isolated mitral regurgitation: implications beyond dimensions.
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DOI：
10.1161/circulationaha.111.073239
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发表时间：
2012-05-15
期刊：
影响因子：
37.8
通讯作者：
Ahmed MI
中科院分区：
文献类型：
--
作者：
Schiros CG;Dell'Italia LJ;Gladden JD;Clark D 3rd;Aban I;Gupta H;Lloyd SG;McGiffin DC;Perry G;Denney TS Jr;Ahmed MI
尽管当左心室 (LV) 收缩末期 (ES) 尺寸 (D) > 40mm 时，二尖瓣反流 (MR) 患者需要手术，但二尖瓣手术后 LV 射血分数 (EF) 可能会降低。我们假设在心脏基部测量的标准超声心动图参数并未反映出手术前显着的左室重塑。 94 名患有退行性孤立 MR 的患者（54±11 岁，38% 女性）接受了电影磁共振成像 (MRI)，并进行了组织标记和三维分析。在 51 名对照受试者（44±14 岁，53% 女性）中，LVES 体积 (V) 与 LVESD 之间呈二次关系，而在 94 名 MR 患者中，这种关系呈三次方关系，表明 MR 患者中每 LVESD 的 LVESV 增加幅度更大。此外，在 MR 患者中，来自汇总的连续短轴切片的 MRI LVESV 显着大于使用 Bullet 公式的 LVESV，这归因于乳头肌尖端远端的更加球形的重塑（P<0.001）。根据现行指南建议，35 名患者接受了二尖瓣修复术。术后 1 年，LVEF 从 61±7 % 降至 54±8 % (P<0.0001)，最大缩短值显着低于正常值 (P<0.0001)。尽管左心室每搏输出量和左心室舒张末期容量/质量比正常化，但术后远端左心室ES三维半径/壁厚比和左心室收缩压指数持续显着增加。尽管 LVESD 明显保留，但 MR 患者表现出显着的球形中段至心尖 LVES 重塑，这导致 LVESV 高于基于标准几何计算的预测。手术后左心室应变减少表明，可能首选对左心室重塑和功能进行体积分析来评估孤立 MR 的疾病进展。
Although surgery is indicated in patients with mitral regurgitation (MR) when left ventricular (LV) end-systolic (ES) dimension (D) is >40mm, LV ejection fraction (EF) may decrease post-mitral valve surgery. We hypothesize that significant LV remodeling pre-surgery is not reflected by standard echocardiographic parameters measured at the base of the heart. 94 patients (54±11 years, 38% female) with degenerative isolated MR underwent cine-magnetic resonance imaging (MRI) with tissue tagging and three-dimensional analysis. In 51 control subjects (44±14 years, 53% female), the relation between LVES volume (V) and LVESD was quadratic, while in 94 MR patients this relation was cubic, indicating greater increase in LVESV per LVESD amongst MR patients. Moreover, MRI LVESV from summated serial short axis slices was significantly greater than LVESV using the Bullet formula in MR patients, attributed to a more spherical remodeling distal to the tips of the papillary muscles (P<0.001). 35 patients underwent mitral valve repair per current guideline recommendations. LVEF decreased from 61±7 to 54±8 % (P<0.0001) and maximum shortening decreased significantly below normal at 1-year post-operatively (P<0.0001). Despite normalization of LV stroke volume and LV end-diastolic volume/mass ratio, there was persistent significant increase in distal LVES three-dimensional radius/wall thickness ratio and LVESV index post-surgery. Despite apparently preserved LVESD, MR patients demonstrate significant spherical mid to apical LVES remodeling that contributes to higher LVESV than predicted by standard geometry-based calculations. Decreased LV strain post-surgery suggests that a volumetric analysis of LV remodeling and function may be preferred to evaluate disease progression in isolated MR.