Assessment of left ventricular function by three-dimensional echocardiography.

Accurate determination of LV volume, ejection fraction and segmental wall motion abnormalities is important for clinical decision-making and follow-up assessment. Currently, echocardiography is the most common used method to obtain this information. Three-dimensional echocardiography has shown to be an accurate and reproducible method for LV quantitation, mainly by avoiding the use of geometric assumptions. In this review, we describe various methods to acquire a 3D-dataset for LV volume and wall motion analysis, including their advantages and limitations. We provide an overview of studies comparing LV volume and function measurement by various gated and real-time methods of acquisition compared to magnetic resonance imaging. New technical improvements, such as automated endocardial border detection and contrast enhancement, will make accurate on-line assessment with little operator interaction possible in the near future

Reverse ventricular remodeling reduces ischemic mitral regurgitation: echo-guided device application in the beating heart. Circulation

Background-In ischemic mitral regurgitation (MR), mitral leaflet closure is restricted by ventricular remodeling with displacement of the papillary muscles (PMs). Therapy is uncertain because ring annuloplasty does not alleviate PM displacement. We tested the hypothesis that echo-guided PM repositioning using an external device can reduce MR without compromising left ventricular (LV) function. Methods and Results-We studied 10 sheep with ischemic MR produced by circumflex ligation with inferior infarction, 6 acutely and 4 eight weeks after myocardial infarction (MI). A Dacron patch containing an inflatable balloon was placed over the PMs and adjusted under echo guidance to reverse LV remodeling and reposition the infarcted PM. 3D echo assessed mitral valve geometric changes. In 7 sheep, sonomicrometry and Millar catheters assessed changes in end-systolic and end-diastolic pressure-volume relationships, and microspheres were injected to assess coronary flow. Moderate MR after MI resolved with patch application alone (nϭ3) or echo-guided balloon inflation, which repositioned the infarcted PM, decreasing the PM tethering distance from 31.1Ϯ2.5 mm after MI to 26.8Ϯ1.8 with patch (PϽ0.01; baselineϭ25.5Ϯ1.5). LV contractility was unchanged (end-systolic slopeϭ3.4Ϯ1.6 mm Hg/mL with patch versus 2.8Ϯ1.6 after MI). Although there was a nonsignificant trend for a mild increase in stiffness constant (0.07Ϯ0.05 m