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In patients with organic mitral regurgitation and normal left ventricular systolic function, mitral valve leaflet flail is associated with reduced shortening of the mitral annulus area
No full textIn patients with ischemic cardiomyopathy and secondary mitral regurgitation, mitral annulus contractile dysfunction is related more to left atrial than to left ventricular contractile dysfunction
No full textWhole blood hypocoagulable profile correlates with the greater risk of death at 28 days in patients with severe sepsis
No full textHypocoagulability and impaired platelet function have been associated to a higher risk of death in sepsis. The aim of our cohort study was to determine whether sepsis-induced hypocoagulability (assessed by ROTEM®) and platelet dysfunction (assessed by MULTIPLATE®) were worse in septic patients who died within the first 28days compared with patients who died between days29-90
Quantitative analysis of mitral annular geometry and function in healthy volunteers using transthoracic three-dimensional echocardiography
Full text linkBACKGROUND: Quantitative assessment of the mitral annulus provides information regarding the pathophysiology of mitral regurgitation and aids in the planning of reparative surgery. Three-dimensional (3D) transthoracic echocardiographic data sets acquired with current scanners have enough spatial and temporal resolution to allow the quantitative analysis of the mitral annulus. Accordingly, the authors performed (1) a validation study to assess the agreement of quantitative analysis of the mitral annulus performed on 3D transthoracic echocardiography (TTE) and 3D transesophageal echocardiography (TEE) and (2) a normative study to obtain the reference values of 3D transthoracic echocardiographic parameters for mitral annular (MA) geometry and dynamics.
METHODS: Mitral valve data sets were obtained by 3D TEE and 3D TTE in 30 consecutive patients with clinically indicated TEE (validation study) and 3D TTE in 224 healthy volunteers (aged 18-76 years) (normative study).
RESULTS: In the validation study, MA measurements obtained by 3D TTE were similar to those obtained by 3D TEE (P = NS). In the normative study, MA analysis by 3D TTE was feasible (94.5%) and reproducible (intraclass correlation coefficient = 0.78-0.97). MA diameters, area, and circumference were correlated with body surface area (r > 0.50 for all) but not with age. Men had larger MA areas than women (4.9 ± 1.0 vs 4.5 ± 0.7 cm(2)/m(2), P = .004). During systole, MA area decreased by 29 ± 5%. This decrease was related mainly to anteroposterior diameter shortening (20 ± 7%).
CONCLUSIONS: MA quantitative analysis by 3D TTE was accurate compared with 3D TEE in unselected patients with mitral valve disease. In healthy subjects, it was highly feasible and reproducible. The availability of reference values for MA geometry and dynamics may foster the implementation of MA quantitative analysis by 3D TTE in clinical settings
Mitral annulus remodeling and dysfunction in patients with mild to severe organic mitral regurgitation
No full textRelationship between mitral annulus function and mitral regurgitation severity and left atrial remodelling in patients with primary mitral regurgitation
No full textAIMS: To explore the relationship between the mitral annular (MA) remodelling and dysfunction, mitral regurgitation (MR) severity, left ventricular (LV) and atrial (LA) size and function in patients with organic MR (OMR).
METHODS AND RESULTS: A total of 52 patients (57 ± 15 years, 31 men) with mild to severe OMR and 52 controls underwent 3D transthoracic echocardiography acquisitions of the mitral valve (MV), LA, and LV. MA geometry and dynamics, LV and LA volumes, LV ejection fraction (LVEF) and emptying fractions (LAEF) were assessed using dedicated software packages. LA and LV myocardial deformations were assessed using 2D speckle-tracking echocardiography. OMR patients presented larger and more spherical MA than controls during the entire systole (P < 0.001). Although the MA non-planarity at early-systole was similar between OMR and controls (157 ± 13° vs. 153 ± 12°, P = NS), the MA became flatter from mid- to end-systole (153 ± 12 vs. 146 ± 10° and 157 ± 12 vs. 147 ± 8°, P < 0.01) in OMR. MA area fractional change was lower in patients with OMR (22 ± 5% vs. 28 ± 5%, P < 0.001), and correlated with the MR orifice and volume (r = -0.52 and r = -0.55). MA fractional area change correlated with LA minimum and maximum volumes (r = 0.77 and r = 0.70), total and active LAEF (r = 0.72 and r = 0.76), and LA negative strain and strain rate (r = 0.52 and r = 0.57), but not with the LVEF or LV global longitudinal strain. In a multivariate regression model using LAEF and LVEF, solely active LAEF correlated with the MA fractional area change (β = 0.51, P = 0.005).
CONCLUSION: In patients with OMR, MA reduced function correlates with the MR severity and the LA size and function, but not with the LV function
Normal mitral annulus dynamics and its relationships with left ventricular and left atrial function
Full text linkMitral annulus (MA) geometry and dynamics are crucial for preserving normal mitral valve (MV) function. Static reference values for MA parameters have been reported, but the normal MA dynamics during the entire cardiac cycle remains controversial. MV full-volume datasets were obtained by three-dimensional transthoracic echocardiography from 50 healthy volunteers (18-74 years; 31 men) to assess MA changes in size and shape during entire cardiac cycle. Using simultaneous multiplanar review, projected MA area (MAA) and circumference (MAC), antero-posterior (AP) and anterolateral-posteromedial (ALPM) diameters, and sphericity index (SphI) were obtained at: mitral valve closure (MVC), mid- and end-systole (ES), early- (EDF) and late-diastolic filling, and end-diastole. MAA and AP diameter were the most "active" parameters, changing in all reference frames (p < 0.001). MAA and AP diameter started to contract before MVC (during the left atrial contraction), reaching their minimum at MVC. Maximum MAA occurred at ES, while maximum AP diameter and SphI occurred at EDF. MAA fractional shortening was 35 ± 10 %. AP diameter change was 25 ± 10 %. MAC, ALPM and SphI showed similar patterns during left ventricular (LV) systole, and remained unchanged during diastole. Fractional change was 35 ± 10 % for MAC, and 13 ± 8 % for ALPM diameter. Our study provides the normal dynamics of the MA during the entire cardiac cycle. It reveals "pre-systolic" contraction of the MA, related to left atrial (LA) contraction, and minimal MAA during early LV systole. Therefore, the normal MA dynamics relates to a "physiologic LA-LV coupling", and a complete MA contraction requires both and properly timed LA and LV systole
Do a vendor-specific and a vendor-independent software for 3D echocardiographic analysis provide similar values for left ventricular volumes and ejection fraction?
No full textPurpose: Intervendor differences of 2D/3D strain measurements are well known issues that significantly limit their adoption in clinical routine. Whether a similar discordance affects also the quantitation of left ventricular (LV) geometry and function and the LV normative ranges for different 3D echo softwares has not been investigated.
Methods: Full-volume LV 3D data sets (35±6 vps) have been acquired in 235 healthy volunteers (44±14 years, range 18–76 years, 104 men) using a GE Vivid E9 scanner. Exclusion criteria were athletic training, pregnancy, body mass index > 30 kg/m2, and poor apical acoustic window. An experienced researcher analyzed all LV data sets using a vendor-specific software (EchoPac BT12, GE Healthcare, N). Three months later, the same researcher repeated the analysis with a vendor-independent DICOM-based software (4D LV Analysis 3.1, TomTec, D), being blinded from previous measurements.
Results: Despite the differences in LV parameters obtained with the two softwares were statistically significant (Table), Bland-Altman analysis shows a clinically irrelevant bias and reasonable limits of agreement for LV volumes and EF. LV mass measurements by EchoPac were slightly larger than those by TomTec and had relatively wider limits of agreement than LV volumes. Both softwares showed significant and consistent relationships of LV 3D parameters with age, gender and body size in healthy subjects (p<0.0001 for all relationships).
Conclusion: Our data shows that converting 3D data sets in DICOM format does not significantly affect the normative values for LV volumes and ejection fraction with respect to those provided by proprietary software. The availability of vendor-independent softwares and respective normative values will encourage the adoption of 3D echocardiography for routine LV quantitation in multi-vendor echo labs
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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