No abstract

Divulgação do autor: Os autores desse artigo não relataram nenhum conflito de interesse atual ou potencial em relação a essa atividade. Os autores e revisores RVT, FASE; Farooq A. Chaudhry, MD, FASE; Robert T. Eberhardt, MD; Benjamin W. Eidem, MD, FASE; Gregory J.Ensing, MD, FASE; Tal Geva, MD, FASE; Kathryn E. Glas, MD, FASE; Sandra Hagen-Ansert, RDCS, RDMS,MS, FASE; Rebecca T. Hahn, MD, FASE; Jeannie Heirs, RDCS; Shunichi Homma, MD; Sanjiv Kaul, MD,FASE; Smadar Kort, MD, FASE; Peg Knoll, RDCS, FASE; Wyman Lai, MD, MPH, FASE; Roberto M. Lang,MD, FASE; Steven Lavine, MD; Steven J. Lester, MD, FASE; Renee Margossian, MD; Victor Mor-Avi,PhD, FASE; Sherif Nagueh, MD, FASE; Alan S. Pearlman, MD, FASE; Patricia A. Pellikka, MD, FASE; MiguelQuinones, MD, FASE; Brad Roberts, RCS, RDCS; Beverly Smulevitz, BS, RDCS, RVS; Kirk T. Spencer,MD, FASE; J. Geoffrey Stevenson, MD, FASE; Wadea Tarhuni, MD, FASE; James D. Thomas, MD; Neil J.Weissman, MD, FASE; Timothy Woods, MD; and William A. Zoghbi, MD, FASE. Os

Background-Tricuspid regurgitation (TR) is an important predictor of morbidity and mortality in heart failure. We aimed to examine the 3D geometry of the tricuspid valve annulus (TVA) in patients with functional TR, comparing them with patients with normal tricuspid valve function and relating annular geometric changes to functional TR. Methods and Results-TVA shape was examined by real-time 3D echocardiography in 75 patients: 35 with functional TR and 40 with normal tricuspid valve function (referent group). The 3D shape of the TVA was reconstructed from rotated 2D planes, and the annular plane was computed by least-squares fitting. Annular area and mediolateral, anteroposterior, and high (superior)-low (inferior) distances were calculated. TR was assessed by vena contracta width. The normal TVA has a bimodal pattern (high-low distanceϭ7.23Ϯ1.05 mm). High points were located anteroposteriorly, and low points were located mediolaterally. With moderate or greater TR (vena contracta width 5.80Ϯ2.62 mm), the TVA became dilated (17.24Ϯ4.75 versus 9.83Ϯ2.18 cm 2 , PϽ0.0001, TR versus referent), more planar with decreased high-low distance (4.14Ϯ1.05 mm), and more circular with decreased ratio of mediolateral/anteroposterior (1.11Ϯ0.09 versus 1.32Ϯ0.09, PϽ0.0001, TR versus referent). Conclusions-The normal TVA has a bimodal shape with distinct high points located anteroposteriorly and low points located mediolaterally. With functional TR, the annulus becomes larger, more planar, and circular. These changes in annular shape with TR have potentially important mechanistic and therapeutic implications for tricuspid valve repair.

Background Accurate quantification of mitral regurgitation (MR) is important for patient treatment and prognosis. Three-dimensional echocardiography allows for the direct measure of the regurgitant orifice area (ROA) by 3D-guided planimetry of the vena contracta area (VCA). We aimed to (1) establish 3D VCA ranges and cutoff values for MR grading, using the American Society of Echocardiography–recommended 2D integrative method as a reference, and (2) compare 2D and 3D methods of ROA to establish a common calibration for MR grading. Methods and Results Eighty-three patients with at least mild MR underwent 2D and 3D echocardiography. Direct planimetry of VCA was performed by 3D echocardiography. Two-dimensional quantification of MR included 2D ROA by proximal isovelocity surface area (PISA) method, vena contracta width, and ratio of jet area to left atrial area. There were significant differences in 3D VCA among patients with different MR grades. As assessed by receiver operating characteristic analysis, 3D VCA at a best cutoff value of 0.41 cm2 yielded 97% of sensitivity and 82% of specificity to differentiate moderate from severe MR. There was significant difference between 2D ROA and 3D VCA in patients with functional MR, resulting in an underestimation of ROA by 2D PISA method by 27% as compared with 3D VCA. Multivariable regression analysis showed functional MR as etiology was the only predictor of underestimation of ROA by the 2D PISA method. Conclusions Three-dimensional VCA provides a single, directly visualized, and reliable measurement of ROA, which classifies MR severity comparable to current clinical practice using the American Society of Echocardiography–recommended 2D integrative method. The 3D VCA method improves accuracy of MR grading compared with the 2D PISA method by eliminating geometric and flow assumptions, allowing for uniform clinical grading cutoffs and ranges that apply regardless of etiology and orifice shape.

Background-Functional mitral regurgitation (MR) is caused by systolic traction on the mitral leaflets related to ventricular distortion. Little is known about whether chronic tethering causes the mitral leaflet area to adapt to the geometric needs imposed by tethering, in part because of inability to reconstruct leaflet area in vivo. Our aim was to explore whether adaptive increases in leaflet area occur in patients with functional MR compared with normal subjects and to test the hypothesis that leaflet area influences MR severity. Methods and Results-A new method for 3-dimensional echocardiographic measurement of mitral leaflet area was developed and validated in vivo against 15 sheep heart valves, later excised. This method was then applied in 80 consecutive patients from 3 groups: patients with normal hearts by echocardiography (nϭ20), patients with functional MR caused by isolated inferior wall-motion abnormality or dilated cardiomyopathy (nϭ29), and patients with inferior wall-motion abnormality or dilated cardiomyopathy but no MR (nϭ31). Leaflet area was increased by 35Ϯ20% in patients with LV dysfunction compared with normal subjects. The ratio of leaflet to annular area was 1.95Ϯ0.40 and was not different among groups, which indicates a surplus leaflet area that adapts to left-heart changes. In contrast, the ratio of total leaflet area to the area required to close the orifice in midsystole was decreased in patients with functional MR compared with those with normal hearts (1.29Ϯ0.15 versus 1.78Ϯ0.39, Pϭ0.001) and compared with patients with inferior wall-motion abnormality or dilated cardiomyopathy but no MR (1.81Ϯ0.38, Pϭ0.001). After adjustment for measures of LV remodeling and tethering, a leaflet-to-closure area ratio Ͻ1.7 was associated with significant MR (odds ratio 23.2, 95% confidence interval 2.0 to 49.1, Pϭ0.02). Conclusions-Mitral leaflet area increases in response to chronic tethering in patients with inferior wall-motion abnormality and dilated cardiomyopathy, but the development of significant MR is associated with insufficient leaflet area relative to that demanded by tethering geometry. The varying adequacy of leaflet adaptation may explain in part the heterogeneity of this disease among patients. The results suggest the need to understand the mechanisms that underlie leaflet adaptation and whether leaflet area can potentially be modified as part of the therapeutic approach.