Quantitative Assessment of Left Ventricular Size and Function

Abstract

Background-Cardiac CT (CCT) and real-time 3D echocardiography (RT3DE) are being used increasingly in clinical cardiology. CCT offers superb spatial and contrast resolution, resulting in excellent endocardial definition. RT3DE has the advantages of low cost, portability, and live 3D imaging without offline reconstruction. We sought to compare both CCT and RT3DE measurements of left ventricular size and function with the standard reference technique, cardiac MR (CMR). Methods and Results-In 31 patients, RT3DE data sets (Philips 7500) and long-axis CMR (Siemens, 1.5 T) and CCT (Toshiba, 16-slice MDCT) images were obtained on the same day without ␤-blockers. All images were analyzed to obtain end-systolic and end-diastolic volumes and ejection fractions using the same rotational analysis to eliminate possible analysis-related differences. Intertechnique agreement was tested through linear regression and Bland-Altman analyses. Repeated measurements were performed to determine intraobserver and interobserver variability. Both CCT and RT3DE measurements resulted in high correlation (r 2 Ͼ0.85) compared with CMR. However, CCT significantly overestimated end-diastolic and end-systolic volumes (26 and 19 mL; PϽ0.05), resulting in a small but significant bias in ejection fraction (Ϫ2.8%). RT3DE underestimated end-diastolic and end-systolic volumes only slightly (5 and 6 mL), with no significant bias in EF (0.3%; Pϭ0.68). The limits of agreement with CMR were comparable for the 2 techniques. The variability in the CCT measurements was roughly half of that in either RT3DE or CMR values. Conclusions-CCT

Automated frame‐by‐frame endocardial border detection from cardiac magnetic resonance images for quantitative assessment of left ventricular function: Validation and clinical feasibility

“…Today, this modality provides multiplane dynamic images of the beating heart with excellent spatial resolution and temporal resolution of 30 phases per cardiac cycle, which is comparable to what has been for many years the standard frame rate in 2D echocardiography. The combination of these features places CMR imaging as the tentative "gold standard" for LV size and function, as reflected by multiple publications in which it was used as such to validate other noninvasive techniques (3)(4)(5)(6)(7)(8)(9)(10)(11)(12).…”

“…trast resolution that has become the standard reference in the assessment of left ventricular (LV) size and function (1,2), against which other techniques are frequently validated (3)(4)(5)(6)(7)(8)(9)(10)(11)(12). However, this technique relies on the detection of endocardial boundaries, which requires frame-by-frame manual tracing on multiple slices, and is thus of limited value in clinical practice.…”

Fração de ejeção e volumes do ventrículo esquerdo medidos com eco 3D e com tomografia ultra-rápida

“…Validation of the analysis of left ventricular ejection fraction and volumes using RT-3D-Echo has been demonstrated in previous studies that used magnetic resonance imaging (MRI) [8][9][10][11] . However, MRI has limitations regarding patients with mechanical prosthesis, pacemakers, metallic devices, or those who are obese or have difficulty to stay in small physical spaces.…”

“…In this context, another investigational imaging method -the 64-slice ultrafast computed tomography (CT), has been used for the structural analysis of the heart, especially of the coronary anatomy. The 64-slice CT provides a better anatomical analysis in relation to echocardiography, whereas the echocardiographic analysis allows better temporal identification in relation to CT. Few studies in the literature have compared echocardiography with CT for the assessment of left ventricular ejection fraction and volumes [11][12][13][14] . Thus, the objective of this study was to compare left ventricular ejection fraction and volumes as measured by RT-3D-Echo and ultrafast 64-slice CT.…”

Echocardiographic evaluation of systolic heart failure

“…The recently validated RT3DE volumetric quantification of global and regional LV function 88 overcomes limitations of 2D echocardiography as it eliminates geometric assumptions, identifies the true LV apex and evaluates wall motion encompassing all planes 89 . Jenkins, et al 90 demonstrated the correlation of RT3DE to MRI with lower intra and inter observer variability, whilst comparing it to computed tomography, Sugeng, et al 91 have shown its superiority in LVEF and volume measurement. RT3DE can assess LV dyssynchrony and demonstrated a greater improvement from CRT with RT3DE guided LV lead placement 92 .…”