Spelling suggestions: "subject:"left ventricular outflow trace"" "subject:"left ventricular outflow track""
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Mitral valve replacement complicated by iatrogenic left ventricular outflow obstruction and paravalvular leak: case report and review of literatureLee, Justin Z., Tey, Kai R., Mizyed, Ahmad, Hennemeyer, Charles T., Janardhanan, Rajesh, Lotun, Kapildeo January 2015 (has links)
BACKGROUND: Left ventricular outflow tract (LVOT) obstruction and paravalvular leak (PVL) are relatively uncommon, but are serious complications of prosthetic valve replacement. CASE PRESENTATION: We present a case that displays the unique therapeutic challenges of treating a patient who developed both LVOT obstruction and mitral PVL after undergoing surgical aortic and mitral valve replacement (MVR). We also describe the use of alcohol septal ablation and albumin-glutaraldehyde (BioGlue) for septal ablation to percutaneously treat the patient's LVOT obstruction, followed by use of an Amplatzer vascular plug for percutaneous closure of an antero-medial mitral PVL associated with severe regurgitation. CONCLUSION: Percutaneous interventional management of these entities may be considered as an initial therapeutic option, especially in high-risk patients with significant morbidity and mortality of repeat surgical operations.
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The Relation of Left Ventricular Geometry to Left Ventricular Outflow Tract Shape and Stroke Volume Index CalculationsLavine, Steven J., Obeng, George B. 01 May 2019 (has links)
Background: Stroke volume (SV) and aortic valve area calculations require the left ventricular (LV) outflow tract (LVOT) or aortic annular area calculations that involve squaring the respective diameters. Area calculation errors became evident with transcatheter aortic valve replacement where areas were underestimated due to an elliptical annulus. We hypothesized that LVOT and annular shape are more elliptical in patients with greater relative LV wall thickness (RWT) leading to underestimation of SV index using 2D Doppler echocardiography. Methods: We studied 203 consecutive patients referred to an outpatient noninvasive laboratory for Doppler echocardiograms which included acceptable 3-dimensional images. 3-dimensional assessment of the LVOT at 3–5 mm from the valve insertion, at the site of valve insertion, and at the sinus of Valsalva (SOV) was performed with assessment of the minor axis (MN), major axis (MJ), and areas at mid-systole. SV index was calculated from LVOT and annular diameters obtained from 2-dimensional echo and from 3-dimensional LVOT areas. Results: An inverse relation of RWT with MN/MJ at mid-systole for the LVOT (r = 0.5812, P < 0.0001) and annulus (r = 0.6865, P < 0.0001) was noted. LVOT and annulus areas were similar among groups at mid-systole. SV index calculated from 2D LVOT dimensions was significantly smaller than using 3D LVOT areas (35.6 ± 8.9 vs 53.6 ± 16.1 mL, P < 0.0001). Conclusion: There is an inverse relation between MN/MJ and RWT at the LVOT and aortic annulus despite the LVOT and annular areas being similar across most geometries resulting in SV index underestimation calculated using LVOT diameters vs 3D LVOT areas.
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Unraveling the Etiologies of Discrete Subaortic Stenosis: A Focus on Left Ventricular Outflow Tract HemodynamicsShar, Jason A. 28 May 2021 (has links)
No description available.
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Effect of ivabradine, a novel I<sub>f</sub> current inhibitor, on dynamic obstruction of the left ventricular outflow tract in cats with preclinical hypertrophic cardiomyopathy: a single-dose studyBlass, Keith Andrew 24 May 2013 (has links)
No description available.
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Investigaton and assessment of ejection murmurs and the left ventricular outflow tract in Boxer dogsKoplitz, Shianne L., DVM 24 August 2005 (has links)
No description available.
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Assessment of Left Ventricular Function and Hemodynamics Using Three-dimensional EchocardiographyShahgaldi, Kambiz January 2010 (has links)
Left ventricular (LV) volumes and ejection fraction (EF) are important predictors of cardiac morbidity and mortality. LV volumes provide valuable prognostic information which isparticularly useful in the selection of therapy or determination of the optimal time for surgery. Two-dimensional (2D) echocardiography is the most widely used non-invasive method forassessment of cardiac function, 2D echocardiography has however several limitations inmeasuring LV volumes and EF since the formulas for quantifications are based on geometricalassumptions. Three-dimensional (3D) echocardiography has been available for almost twodecades, although the use of this modality has not gained wide spread acceptance. 3D echocardiography can overcome the above mentioned limitation in LV volume and EF evaluation since it is not based on geometrical assumption. 3D echocardiography has been shownin several studies to be more accurate and reproducible with low inter- and intraobservervariability in comparison to 2D echocardiography regarding the measurements of LV volumesand EF. The overall aim of the thesis was to evaluate the feasibility and accuracy of 3D echocardiography based-methods in the clinical context. In Study I the feasibility of 3D echocardiography was investigated for determination of LV volumes and EF using parasternal, apical and subcostal approaches. The study demonstrated that the apical 3D echocardiography view offers superior visualization. Study II tested the possibility of creating flow-volume loops to differentiate patients with valvular abnormalities from normal subjects. There were significant differences in the pattern from flow-volume loops clearly separating the groups. In Study III the visual estimation, “eyeballing” of EF was evaluated with two- and tri-plane echocardiography in comparison to quantitative 3D echocardiography. The study confirmed that an experienced echocardiographer can, with a high level of agreement estimate EF both with two- and tri-plane echocardiography. Study IV exposed the high accuracy of stroke volume and cardiac output determination using a3D biplane technique by planimetrically tracing the left ventricular outflow tract and indicating that an assumption of circular left ventricular outflow tract is not reliable. In Study V, two 3D echocardiography modalities, single-beat and four-beat ECG-gated 3D echocardiography were evaluated in patients having sinus rhythm and atrial fibrillation. Thesingle-beat technique showed significantly lower inter-and intraobserver variability in LV volumes and EF measurements in patients having atrial fibrillation in comparison to four-beat ECG-gated acquisition due to absence of stitching artifact. All studies demonstrated good results suggesting 3D echocardiography to be a feasible andaccurate method in daily clinical settings. / degree of Medical DoctorQC 20100629
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Core Lab Adjudication of the ACURATE neo2 Hemodynamic Performance Using Computed-Tomography-Corrected Left Ventricular Outflow Tract AreaElkoumy, Ahmed, Rück, Andreas, Kim, Won-Keun, Abdel-Wahab, Mohamed, Abdelshafy, Mahmoud, De Backer, Ole, Elzomor, Hesham, Hengstenberg, Christian, Mohamed, Sameh K., Saleh, Nawzad, Arsang-Jang, Shahram, Bjursten, Henrik, Simpkin, Andrew, Meduri, Christopher U., Soliman, Osama 23 May 2024 (has links)
(1) Background: Hemodynamic assessment of prosthetic heart valves using conventional
2D transthoracic Echocardiography-Doppler (2D-TTE) has limitations. Of those, left ventricular
outflow tract (LVOT) area measurement is one of the major limitations of the continuity equation,
which assumes a circular LVOT. (2) Methods: This study comprised 258 patients with severe aortic
stenosis (AS), who were treated with the ACURATE neo2. The LVOT area and its dependent Dopplerderived
parameters, including effective orifice area (EOA) and stroke volume (SV), in addition
to their indexed values, were calculated from post-TAVI 2D-TTE. In addition, the 3D-LVOT area
from pre-procedural MDCT scans was obtained and used to calculate corrected Doppler-derived
parameters. The incidence rates of prosthesis patient mismatch (PPM) were compared between the
2D-TTE and MDCT-based methods (3) Results: The main results show that the 2D-TTE measured
LVOT is significantly smaller than 3D-MDCT (350.4 62.04 mm2 vs. 405.22 81.32 mm2) (95%
Credible interval (CrI) of differences: 55.15, 36.09), which resulted in smaller EOA (2.25 0.59 vs.
2.58 0.63 cm2) (Beta = 0.642 (95%CrI of differences: 0.85, 0.43), and lower SV (73.88 21.41 vs.
84.47 22.66 mL), (Beta = 7.29 (95% CrI: 14.45, 0.14)), respectively. PPM incidence appears more
frequent with 2D-TTE- than 3D-MDCT-corrected measurements (based on the EOAi) 8.52% vs. 2.32%,
respectively. In addition, significant differences regarding the EOA among the three valve sizes (S, M
and L) were seen only with the MDCT, but not on 2D-TTE. (4) Conclusions: The corrected continuity
equation by combining the 3D-LVOT area from MDCT with the TTE Doppler parameters might
provide a more accurate assessment of hemodynamic parameters and PPM diagnosis in patients
treated with TAVI. The ACURATE neo2 THV has a large EOA and low incidence of PPM using the
3D-corrected LVOT area than on 2D-TTE. These findings need further confirmation on long-term
follow-up and in other studies.
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Leaflet Material Selection for Aortic Valve RepairAbessi, Ovais 21 November 2013 (has links)
Leaflet replacement in aortic valve repair (AVr) is associated with increased long-term repair failure. Hemodynamic performance and mechanical stress levels were investigated after porcine AVr with 5 types of clinically relevant replacement materials to ascertain which material(s) would be best suited for repair. Porcine aortic roots with intact aortic valves were placed in a left-heart simulator mounted with a high-speed camera for baseline valve assessment. Then, the non-coronary leaflet was excised and replaced with autologous porcine pericardium (APP), glutaraldehyde-fixed bovine pericardial patch (BPP; Synovis™), extracellular matrix scaffold (CorMatrix™), or collagen-impregnated Dacron (HEMASHIELD™). Hemodynamic parameters were measured over a range of cardiac outputs (2.5–6.5L/min) post-repair. Material properties of the above materials along with St. Jude Medical™ Pericardial Patch with EnCapTM Technology (SJM) were determined using pressurization experiments. Finite element models of the aortic valve and root complex were then constructed to verify the hemodynamic characteristics and determine leaflet stress levels.
This study demonstrates that APP and SJM have the closest profiles to normal aortic valves; therefore, use of either replacement material may be best suited. Increased stresses found in BPP, HEMASHIELD™, and CorMatrix™ groups may be associated with late repair failure.
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Leaflet Material Selection for Aortic Valve RepairAbessi, Ovais January 2013 (has links)
Leaflet replacement in aortic valve repair (AVr) is associated with increased long-term repair failure. Hemodynamic performance and mechanical stress levels were investigated after porcine AVr with 5 types of clinically relevant replacement materials to ascertain which material(s) would be best suited for repair. Porcine aortic roots with intact aortic valves were placed in a left-heart simulator mounted with a high-speed camera for baseline valve assessment. Then, the non-coronary leaflet was excised and replaced with autologous porcine pericardium (APP), glutaraldehyde-fixed bovine pericardial patch (BPP; Synovis™), extracellular matrix scaffold (CorMatrix™), or collagen-impregnated Dacron (HEMASHIELD™). Hemodynamic parameters were measured over a range of cardiac outputs (2.5–6.5L/min) post-repair. Material properties of the above materials along with St. Jude Medical™ Pericardial Patch with EnCapTM Technology (SJM) were determined using pressurization experiments. Finite element models of the aortic valve and root complex were then constructed to verify the hemodynamic characteristics and determine leaflet stress levels.
This study demonstrates that APP and SJM have the closest profiles to normal aortic valves; therefore, use of either replacement material may be best suited. Increased stresses found in BPP, HEMASHIELD™, and CorMatrix™ groups may be associated with late repair failure.
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