Biomedical subjects

Giuseppe Saracino

Publications and source records attributed to Giuseppe Saracino.

5 recordsLinked to original sources

PubMed2006

Three-dimensional geometry of the tricuspid annulus in healthy subjects and in patients with functional tricuspid regurgitation: a real-time, 3-dimensional echocardiographic study.

BACKGROUND: Most rings currently used for tricuspid valve annuloplasty are formed in a single plane, whereas the actual tricuspid annulus (TA) may have a nonplanar or 3-dimensional (3D) structure. The purpose of this study was therefore to investigate the 3D geometry of the TA in healthy subjects and in patients with functional tricuspid regurgitation (TR). METHODS AND RESULTS: This study consisted of 15 healthy subjects and 16 patients with functional TR who had real-time 3D echocardiography. With our customized software, 8 points along the TA were determined with the rotated plane around the axis at 45 degrees intervals. The TA was traced during a cardiac cycle. The distance between diagonals connecting 2 points was measured. The height was defined as the distance from the plane determined by least-squares regression analysis at all 8 points. Both the maximum (7.5+/-2.1 versus 5.6+/-1.0 cm2/m2) and minimum (5.7+/-1.3 versus 3.9+/-0.8 cm2/m2) TA areas in patients with TR were larger than those in healthy subjects (both P<0.01). Healthy subjects had a nonplanar-shaped TA with homogeneous contraction. The posteroseptal portion was the lowest toward the apex from the right atrium, and the anteroseptal portion was the highest. In patients with functional TR, the TA was dilated in the septal to lateral direction, resulting in a more circular shape than in healthy subjects. A similar 3D pattern was observed in patients with TR, but it was more planar than that in healthy subjects. CONCLUSIONS: Real-time 3D echocardiography showed a complicated 3D structure of the TA, which appeared to be different from the "saddle-shaped" mitral annulus, suggesting an annuloplasty for TR different from that for mitral regurgitation.

Adult↗

PubMed2005

Automated mitral annular tracking: a novel method for evaluating mitral annular motion using two-dimensional echocardiography.

We developed an automated mitral annular tracking method based on a digital processing of high frame rate cineloop images of 2-dimensional echocardiography. In this study, its feasibility and accuracy was validated in 11 healthy volunteers and 16 patients with left ventricular (LV) dysfunction. The mitral annular excursion measured by automated mitral annular tracking agreed well with that measured by 3-dimensional echocardiography and correlated with LV ejection fraction. The longitudinal mitral annular excursion was reduced whereas the radial one was preserved for patients with LV dysfunction compared with control subjects. The novel automated mitral annular tracking method is clinically feasible and has potential capability to quantify the comprehensive mitral annular motion for evaluating LV function in a clinical setting.

Adult↗

PubMed2004

Echocardiographic assessment of regional ventricular function after device-based change of left ventricular shape.

We assessed the effects of implantation of Myosplint (Myocor, Maple Grove, Minn), a device that changes left ventricular (LV) cross-sectional shape from circular to bilobar, on regional LV function. A total of 10 open-chest dogs with tachycardia-induced cardiomyopathy were studied before and after Myosplint implantation. LV cross-sectional epicardial echocardiography at the papillary muscle level was performed along with acquisition of hemodynamic data. LV normalized thickening, fractional thickening, end-diastolic thickness, and end-diastolic curvatures were calculated for 10 LV segments. Myosplint implantation did not affect LV hemodynamics, but decreased average end-diastolic curvature (P <.0001) and increased its segmental heterogeneity (P <.0001). There was no change in average fractional thickening, whereas normalized thickening increased (P =.05). In contrast, segmental heterogeneity of both normalized and fractional thickening increased (P =.02 and P =.01, respectively). Structural modeling confirmed that Myosplint implantation increases regional stress heterogeneity and curvature heterogeneity. LV cross-sectional shape markedly affects regional LV performance.

Animals↗

PubMed2004

Mitral annular motion as a surrogate for left ventricular ejection fraction: real-time three-dimensional echocardiography and magnetic resonance imaging studies.

AIMS: To validate the accuracy of mitral annular motion assessed by real-time three-dimensional echocardiography (RT3DE) as a surrogate for determination of the left ventricular function in comparison with magnetic resonance imaging (MRI). METHODS AND RESULTS: Forty-seven patients with a variety of cardiac pathologies underwent both RT3DE and MRI exams. After 3D data sets were transferred to a PC with a custom-made program, nine consecutive rotational apical plane images (20 degrees apart) were displayed. The two mitral leaflet insertion points were manually identified in each plane. The geometry of the mitral annulus was reconstructed from a total of 18 coordinates (x, y, z), and the changes in mitral annular area and mitral annular motion along the apical long axis were calculated. The left ventricular ejection fraction (LVEF) determined by MRI was 41+/-18%, and 24 patients had LVEF<50%. Mitral annular motion (y) obtained by RT3DE was 11+/-5 mm and correlated moderately well with LVEF (x) measured by MRI (r=0.84, y=0.25x+0.43, p<0.0001). The mitral annular motion<12 mm was a good threshold for detecting LVEF<50% with 96% sensitivity, 85% specificity, and 91% accuracy. CONCLUSION: Mitral annular motion determined by RT3DE correlated moderately well with LVEF; and systolic motion, <12 mm, accurately detected LV dysfunction.

Adult↗

PubMed2002

Left ventricular volume estimation for real-time three-dimensional echocardiography.

The application of level set techniques to echocardiographic data is presented. This method allows semiautomatic segmentation of heart chambers, which regularizes the shapes and improves edge fidelity, especially in the presence of gaps, as is common in ultrasound data. The task of the study was to reconstruct left ventricular shape and to evaluate left ventricular volume. Data were acquired with a real-time three-dimensional (3-D) echocardiographic system. The method was applied directly in the three-dimensional domain and was based on a geometric-driven scheme. The numerical scheme for solving the proposed partial differential equation is borrowed from numerical methods for conservation law. Results refer to in vitro and human in vivo acquired 3-D + time echocardiographic data. Quantitative validation was performed on in vitro balloon phantoms. Clinical application of this segmentation technique is reported for 20 patient cases providing measures of left ventricular volumes and ejection fraction.

Echocardiography, Three-Dimensional↗