Wendy Tsang

Recommendations for Cardiac Chamber Quantification by Echocardiography in Adults: An Update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging

The rapid technological developments of the past decade and the changes in echocardiographic practice brought about by these developments have resulted in the need for updated recommendations to the previously published guidelines for cardiac chamber quantification, which was the goal of the joint writing group assembled by the American Society of Echocardiography and the European Association of Cardiovascular Imaging. This document provides updated normal values for all four cardiac chambers, including three-dimensional echocardiography and myocardial deformation, when possible, on the basis of considerably larger numbers of normal subjects, compiled from multiple databases. In addition, this document attempts to eliminate several minor discrepancies that existed between previously published guidelines.

EAE/ASE recommendations for image acquisition and display using three-dimensional echocardiography.

Roberto M. Lang, MD, FASE*‡, Luigi P. Badano, MD, FESC†‡, Wendy Tsang, MD*, David H. Adams, MD*, Eustachio Agricola, MD†, Thomas Buck, MD, FESC†, Francesco F. Faletra, MD†, Andreas Franke, MD, FESC†, Judy Hung, MD, FASE*, Leopoldo Pérez de Isla, MD, PhD, FESC†, Otto Kamp, MD, PhD, FESC†, Jaroslaw D. Kasprzak, MD, FESC†, Patrizio Lancellotti, MD, PhD, FESC†, Thomas H. Marwick, MBBS, PhD*, Marti L. McCulloch, RDCS, FASE*, Mark J. Monaghan, PhD, FESC†, Petros Nihoyannopoulos, MD, FESC†, Natesa G. Pandian, MD*, Patricia A. Pellikka, MD, FASE*, Mauro Pepi, MD, FESC†, David A. Roberson, MD, FASE*, Stanton K. Shernan, MD, FASE*, Girish S. Shirali, MBBS, FASE*, Lissa Sugeng, MD*, Folkert J. Ten Cate, MD†, Mani A. Vannan, MBBS, FASE*, Jose Luis Zamorano, MD, FESC, FASE†, and William A. Zoghbi, MD, FASE*

Age-Related Normal Range of Left Ventricular Strain and Torsion Using Three-Dimensional Speckle-Tracking Echocardiography

BACKGROUNDnThree-dimensional (3D) speckle-tracking echocardiography (STE) is an emerging technology used to quantify left ventricular (LV) function. However, the accuracy and normal values of LV strain and twistxa0using 3D STE have not been established in a large group of normal subjects. The aims of this study were to (1) to evaluate the accuracy of 3D STE analysis of LV strain against a cardiac magnetic resonance (CMR) reference and (2) to establish age-related normal values of LV strain and torsion using real-time 3D echocardiographic (RT3DE) images.nnnMETHODSnIn protocol 1, RT3DE data sets and CMR images were acquired on the same day in 19 patients referred for clinically indicated CMR. Global LV longitudinal, circumferential, and radial strain was compared between the two modalities. In protocol 2, global and regional strain and twist and torsion were measured in 313 healthy subjects using 3D STE.nnnRESULTSnIn protocol 1, good correlations for each LV strain component were noted between RT3DE imagingxa0and CMR (rxa0= 0.61-0.86, P < .001). In protocol 2, normal global longitudinal, circumferential, radial,xa0and 3D strain were -20.3 ± 3.2%, -28.9 ± 4.6%, 88.0 ± 21.8%, and -37.6 ± 4.8%, respectively. A significant age dependency was observed for global longitudinal and 3D strain. Aging also affected LV torsion: the lowest values were found in children and adolescents, and values subsequently increased withxa0age, while further aging was associated with a gradual reduction in basal rotation accompanied by an increase in apical rotation.nnnCONCLUSIONSnThis study provides initial validation of 3D strain analysis from RT3DE images and reference values of normal 3D LV strain and torsion. The age-related differences in LV strain and torsion may reflect myocardial maturation and aging.

Valvular heart disease. The value of 3-dimensional echocardiography.

Significant advances in 3-dimensional echocardiography (3DE) technology have ushered its use into clinical practice. The recent advent of real-time 3DE using matrix array transthoracic and transesophageal transducers has resulted in improved image spatial resolution, and therefore, enhanced visualization of the pathomorphological features of the cardiac valves compared with previously used sparse array transducers. It has enabled an unparalleled real-time visualization of valves and subvalvular anatomic features from a single volume acquisition without the need for offline reconstruction. On-cart or offline post-processing using commercially available and custom 3-dimensional analysis software allows the quantification of multiple parameters, such as orifice area, prolapse height and volume in mitral valve disease, area of the left ventricular outflow tract, and tricuspid annular geometry. In this review, we discuss the incremental role of 3DE in evaluating valvular anatomic features, volumetric quantification, pre-surgical planning, intraprocedural guidance, and post-procedural assessment of valvular heart disease.

Accuracy of aortic annular measurements obtained from three-dimensional echocardiography, CT and MRI: human in vitro and in vivo studies

Objectives To determine the accuracy of calcium-containing rings measurements imaged by three-dimensional echocardiography (3DE), multi-slice CT (MSCT) and cardiac magnetic resonance (CMR) under ideal conditions against the true ring dimensions. To compare the accuracy of aortic annulus (AoA) measurements in ex vivo human hearts using 3DE, MSCT and CMR. To determine the accuracy of AoA measurements in an in vivo human model. Design 3DE, MSCT and CMR imaging were performed on 30 calcium-containing rings and 28 explanted human hearts. Additionally, 15 human subjects with clinical indication for MSCT underwent 3DE. Two experts in each modality measured the images. Main outcome measures Bias and intraclass correlation coefficient for accuracy of imaging measurements when compared with actual ring dimensions. Bias, intraclass correlation coefficient and variability were obtained: (1) when comparing explanted human heart AoA measurements from the two remaining imaging modalities with the most accurate one as determined from the ring measurements and (2) in in vivo human AoA measurements. Analysis was repeated on explanted heart subgroups divided by aortic valve Agatston score. Results Against the known ring dimensions, CMR had the highest accuracy and the lowest variability. MSCT measurements had high accuracy but wider variability and 3DE had the lowest accuracy with the largest variability. When 3DE and MSCT were compared with CMR, 3DE underestimated and MSCT overestimated AoA dimensions, but inter-measurement variability of 3DE and MSCT were similar. When divided by Agatston score, both 3DE and MSCT measurements were larger and showed greater variability with increasing calcium burden. The in vivo study showed that the correlation between 3DE and MSCT measurements was high; however, 3DE measurements were smaller than those measured with MSCT. Conclusions In the in vitro model, CMR measurements were the most accurate for assessing the actual dimensions suggesting that further investigations on its role in AoA measurement in TAVR are needed. However from the in vivo model, MSCT and 3DE are reasonable alternatives with the understanding that they can slightly overestimate and underestimate annular dimensions, respectively.

Synthesis of Extracellular Matrix and Adhesion Through β1 Integrins Are Critical for Fetal Ventricular Myocyte Proliferation

Extracellular matrix (ECM) regulates vascular smooth muscle cell proliferation. The role of ECM in myocardial growth is unexplored. We sought to determine whether human fetal ventricular myocytes (HFVMs) produce ECM and whether synthesis and attachment to ECM are necessary for their epidermal growth factor (EGF)–dependent and –independent proliferation. Cultured HFVMs proliferate in the presence but not absence of serum and EGF, as determined by increase in cell number and [3H]thymidine and [14C]leucine incorporation (measures of DNA and protein synthesis, respectively). Using a cyanogen bromide digestion technique to measure collagen and elastin and using affinity chromatography for fibronectin, we found that HFVMs synthesized collagen and fibronectin but not elastin. HFVMs grown on exogenous ECM (including fibronectin and type I collagen and laminin) demonstrated no change in proliferation or DNA and protein synthesis with or without EGF. However, inhibition of collagen synthesis using cis-4-hydroxyproline resulted in a decrease in EGF-related HFVM proliferation and DNA and protein synthesis, which was reversed by exposure to l-proline but not by growth on type I collagen. Use of &bgr;1 but not &bgr;3 integrin antibody to inhibit cell interaction with ECM resulted in a decrease in HFVM proliferation and DNA and protein synthesis in response to EGF. Furthermore, EGF-dependent proliferation was enhanced by &agr;1&bgr;1 and &agr;5&bgr;1 antibodies that act as functional ligands, but not &agr;3&bgr;1, the only &bgr;1 subtype expressed in adult myocytes. In conclusion, proliferating HFVMs synthesize collagen and fibronectin. The proliferative response of HFVMs to EGF requires the synthesis of collagen as well as attachment to specific &agr;/&bgr;1 integrin heterodimers.

Echocardiographic Evaluation of Cardiac Amyloid

Cardiac involvement in amyloidosis has poor prognosis and its diagnosis is challenging because of its patchy, infiltrative nature. Echocardiography plays an important role in the diagnosis, management, and prognosis in this disease process. In this article, we briefly review the utility and problems associated with traditional echocardiographic techniques and discuss the role for new echocardiographic imaging modalities such as tissue Doppler, Doppler-based strain, speckle tracking imaging, and three-dimensional imaging in the assessment of cardiac amyloid.

Amiodarone-induced thyrotoxicosis: A review

BACKGROUNDnAmiodarone-induced thyrotoxicosis (AIT) develops in 3% of amiodarone-treated patients in North America. AIT is classified as type 1 or type 2. Type 1 AIT occurs in patients with underlying thyroid pathology such as autonomous nodular goiter or Graves disease. Type 2 AIT is a result of amiodarone causing a subacute thyroiditis with release of preformed thyroid hormones into the circulation.nnnOBJECTIVESnTo review the literature and present an overview of the differentiation between and management of type 1 and type 2 AIT.nnnMETHODSnPubMed, the Cumulative Index to Nursing and Allied Health Literature and Medscape searches of all available English language articles from 1983 to 2006 were performed. Search terms included amiodarone -induced thyrotoxicosis, complications, management, treatment and colour flow Dopper sonography.nnnRESULTSnThere is evidence to suggest that to differentiate between type 1 and type 2 AIT, a careful history and physical examination should be performed to identify pre-existing thyroid disease. An iodine-131 uptake test and colour flow Doppler sonography should be performed. Patients with type 2 AIT should receive a trial of glucocorticoids, whereas those with type 1 should receive antithyroid therapy. For patients in whom the mechanism of the thyrotoxicosis is unclear, a combination of prednisone and antithyroid therapy may be considered.

Rapid Estimation of Left Ventricular Function Using Echocardiographic Speckle-Tracking of Mitral Annular Displacement

BACKGROUNDnLeft ventricular (LV) ejection fraction (EF) by transthoracic two-dimensional echocardiography is time-intensive and highly dependent on image quality. Mitral annular displacement (MAD) qualitatively correlates with EF and can be measured in patients with poor image quality and dropout. The authors hypothesized that speckle-tracking echocardiography (STE)-derived MAD could quantify EF accurately and tested this hypothesis using cardiac magnetic resonance (CMR) as a reference.nnnMETHODSnOne hundred eighteen patients undergoing clinical transthoracic echocardiography were screened, and 110 whose mitral annuli was sufficiently well-defined irrespective of LV endocardial visualization underwent CMR within 6 days (85 of 110 in 1 day). Reference CMR EF values were obtained using standard methodology. STE was used to track annular motion throughout the cardiac cycle in the apical 2-chamber and 4-chamber views. To establish the relationship between MAD and CMR EF and to obtain a formula to estimate EF from MAD, regression analysis was performed in a study group of 60 patients with a wide range of EFs. This formula was then used in an independent test group of 50 patients by comparing estimated MAD EF against CMR EF values using Pearsons correlation and Bland-Altman analyses.nnnRESULTSnIn the study group, STE MAD correlated highly with CMR EF and resulted in a formula relating MAD to EF. In the test group, estimated EF correlated well with CMR EF (4-chamber, R(2) = 0.64; 2-chamber, R(2) = 0.55), with near-zero bias and acceptable limits of agreement. Intraobserver and interobserver variability were between 5.8% and 12.7%.nnnCONCLUSIONSnSTE MAD is a clinically useful tool for quick, easy, robust, and accurate estimates of EF irrespective of LV endocardial definition.

A three-dimensional echocardiographic study on aortic–mitral coupling in transcatheter aortic valve replacement

AIMSnNormal aortic valve (AV) and mitral valve (MV) function in a reciprocal interdependent fashion. We hypothesized that MV function would be affected by severe aortic stenosis (AS) and that it would remain altered after transcatheter AV replacement (TAVR). Using three-dimensional (3D) echocardiography, we studied aortic-mitral coupling in patients with severe AS undergoing TAVR and compared them with controls.nnnMETHODS AND RESULTSnThree-dimensional transoesophageal echocardiography (Philips iE33) was performed on 43 patients: 27 with severe AS studied pre- and post-TAVR and 16 controls. A custom software tracked the aortic annulus (AoA) and mitral annulus (MA), allowing dynamic automated measurements of AoA and MA morphology, angle, and motion. The AS pre-TAVR patients had significantly reduced MA displacement, MA area, and maximum AoA area compared with the controls. Post-TAVR, MA displacement, MA area, and AoA area remained reduced. End-systolic AoA-MA angle was significantly wider in the AS patients compared with the controls and remained wider post-TAVR. Pre-TAVR, there was no difference in MA or AoA dynamics between patients with mild vs. moderate-to-severe MA calcium; Edwards-Sapien vs. a Medtronic CoreValve valve; normal vs. reduced left ventricular systolic function whereas post-TAVR, MA dynamics were significantly reduced in those with moderate-to-severe MA calcium.nnnCONCLUSIONnThis is the first study to demonstrate that AS can affect a secondary unaffected valve, the MV, due to the calcification in the aortic-mitral fibrous continuity. TAVR does not result in recovery of MV structure. These changes have implications in the future TAVR valve development and the possible need for MV assessment pre- and post-TAVR.