用于评估瓣下重塑的二尖瓣帐篷指数。

Mitral valve tenting index for assessment of subvalvular remodeling.

作者信息

Ryan Liam P, Jackson Benjamin M, Parish Landi M, Sakamoto Hiroaki, Plappert Theodore J, St John-Sutton Martin, Gorman Joseph H, Gorman Robert C

机构信息

Harrison Department of Surgical Research, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.

出版信息

Ann Thorac Surg. 2007 Oct;84(4):1243-9. doi: 10.1016/j.athoracsur.2007.05.005.

DOI:10.1016/j.athoracsur.2007.05.005

PMID:17888976

Abstract

BACKGROUND

Ischemic mitral regurgitation results from a variable combination of annular dilatation and remodeling of the subvalvular apparatus. Current surgical techniques effectively treat annular dilatation, but methods for addressing subvalvular remodeling have not been standardized. An effective technique for determining the extent of subvalvular remodeling could improve surgical results by identifying patients who are unlikely to benefit from annuloplasty alone.

METHODS

A well-characterized ovine model of ischemic mitral regurgitation was used. Real-time three-dimensional echocardiography was performed on each animal at baseline and at 1 hour and 8 weeks after infarction. Multiple valvular geometric measurements were calculated at each time point.

RESULTS

Immediate and long-term changes in mitral valvular geometry were observed. Annular height-to-commissural width ratio decreased from 20.0% +/- 1.6% to 11.2% +/- 0.9% 1 hour after infarction (p < 0.001) and to 9.4% +/- 0.4% 8 weeks after infarction (p < 0.001), whereas mitral annular area increased from 8.1 +/- 0.3 cm2 to 9.2 +/- 0.4 cm2 (p < 0.05) and then to 10.5 +/- 0.6 cm2 (p < 0.05). Maximum mitral valve tenting area increased from 49.7 +/- 5.1 mm2 to 58.6 +/- 4.2 mm2 (p < 0.05) and then to 106.4 +/- 3.9 mm2 (p < 0.001), whereas mitral valve tenting volume increased from 679.0 +/- 75.5 mm3 to 828.6 +/- 102.4 mm3 (p = 0.050) and then to 1530.5 +/- 97.8 mm3 (p < 0.001). The mitral valve tenting index increased from 0.83 +/- 0.08 mm to 0.88 +/- 0.08 mm (p > 0.05) and then to 1.46 +/- 0.08 mm (p < 0.001).

CONCLUSIONS

We have described a technique that uses real-time three-dimensional echocardiography to perform a comprehensive assessment of leaflet tethering on the entire mitral valve. Our methodology is not influenced by viewing plane selection, regional tenting asymmetry, or annular dilatation and therefore represents a potentially useful, clinically relevant, and consistent measure of subvalvular remodeling.

摘要

背景

缺血性二尖瓣反流由瓣环扩张和瓣下装置重塑的多种不同组合导致。目前的外科技术能有效治疗瓣环扩张，但处理瓣下重塑的方法尚未标准化。一种确定瓣下重塑程度的有效技术，可通过识别那些不太可能仅从瓣环成形术中获益的患者来改善手术效果。

方法

使用一个特征明确的缺血性二尖瓣反流羊模型。在基线、梗死1小时后和梗死8周后对每只动物进行实时三维超声心动图检查。在每个时间点计算多个瓣膜几何测量值。

结果

观察到二尖瓣几何形状的即时和长期变化。瓣环高度与连合宽度比在梗死后1小时从20.0%±1.6%降至11.2%±0.9%（p<0.001），在梗死后8周降至9.4%±0.4%（p<0.001），而二尖瓣瓣环面积从8.1±0.3 cm²增加到9.2±0.4 cm²（p<0.05），然后增加到10.5±0.6 cm²（p<0.05）。二尖瓣最大帐篷面积从49.7±5.1 mm²增加到58.6±4.2 mm²（p<0.05），然后增加到106.4±3.9 mm²（p<0.001），而二尖瓣帐篷体积从679.0±75.5 mm³增加到828.6±102.4 mm³（p=0.050），然后增加到1530.5±97.8 mm³（p<0.001）。二尖瓣帐篷指数从0.83±0.08 mm增加到0.88±0.08 mm（p>0.05），然后增加到1.46±0.08 mm（p<0.001）。