Quantitation of mitral valve tenting in ischemic mitral regurgitation by transthoracic real-time three-dimensional echocardiography.

OBJECTIVES We sought to investigate the geometric changes of the mitral leaflets and annulus, clarify the maximum tenting site of the leaflets, and quantify the valve tenting in ischemic mitral regurgitation (MR) using three-dimensional (3D) echocardiography. BACKGROUND Although the understanding of the mechanisms of ischemic MR has advanced recently, the geometric changes of the mitral leaflets and annulus have been assessed by two-dimensional echocardiography in the clinical setting, despite the unique configuration of the leaflets and annulus. METHODS Utilizing real-time 3D echocardiography, we obtained transthoracic volumetric images in 12 patients with ischemic MR presenting with global left ventricular dysfunction and in 10 controls. Original software was used to crop the 3D data into 18 radial planes, and we marked the mitral annulus and leaflets in each plane in mid-systole. The 3D images of the leaflets and annulus were reconstructed for the quantitative measurements. RESULTS In ischemic MR, the annulus flattened with apparent tenting of the leaflets. Maximum and mean tenting length were longer and tenting volume was larger in ischemic MR than control subjects (maximum tenting length: 9.8 +/- 2.0 mm vs. 3.1 +/- 1.2 mm, p < 0.0001, mean tenting length: 3.7 +/- 0.9 mm vs. 0.7 +/- 0.5 mm, p < 0.0001, tenting volume: 4.09 +/- 1.22 ml vs. 0.45 +/- 0.29 ml, p < 0.0001). The maximum tenting site was located in anterior leaflet in all patients. CONCLUSIONS We clearly demonstrated 3D geometric deformity of the mitral leaflets and annulus in ischemic MR using novel software for creating images by 3D echocardiography. This technique will be helpful in making a proper decision for the surgical strategy in each patient.