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61.
BackgroundMitral leaflet enlargement has been identified as an adaptive mechanism to prevent mitral regurgitation in dilated left ventricles (LVs) caused by chronic aortic regurgitation (AR). This enlargement is deficient in patients with functional mitral regurgitation, which remains frequent in the population with ischemic cardiomyopathy. Maladaptive fibrotic changes have been identified in post-myocardial infarction (MI) mitral valves. It is unknown if these changes can interfere with valve growth and whether they are present in other valves.ObjectivesThis study sought to test the hypothesis that MI impairs leaflet growth, seen in AR, and induces fibrotic changes in mitral and tricuspid valves.MethodsSheep models of AR, AR + MI, and controls were followed for 90 days. Cardiac magnetic resonance, echocardiography, and computed tomography were performed at baseline and 90 days to assess LV volume, LV function, mitral regurgitation and mitral leaflet size. Histopathology and molecular analyses were performed in excised valves.ResultsBoth experimental groups developed similar LV dilatation and dysfunction. At 90 days, mitral valve leaflet size was smaller in the AR + MI group (12.8 ± 1.3 cm2 vs. 15.1 ± 1.6 cm2, p = 0.03). Mitral regurgitant fraction was 4% ± 7% in the AR group versus 19% ± 10% in the AR + MI group (p = 0.02). AR + MI leaflets were thicker compared with AR and control valves. Increased expression of extracellular matrix remodeling genes was found in both the mitral and tricuspid leaflets in the AR + MI group.ConclusionsIn these animal models of AR, the presence of MI was associated with impaired adaptive valve growth and more functional mitral regurgitation, despite similar LV size and function. More pronounced extracellular remodeling was observed in mitral and tricuspid leaflets, suggesting systemic valvular remodeling after MI.  相似文献   
62.

Background

Isolated tricuspid valve replacement is rare when performed as a re-operation after a left side operation. It is important to know the factors that determine mortality and morbidity. Tricuspid Annular Plane Systolic Excursion (TAPSE) is a scoring system that is used with non-invasive Doppler echocardiography to determine right ventricular (RV) function. This study analyzed TAPSE scores and adverse outcomes of isolated tricuspid valve surgery in patients with previous cardiac surgery.

Methods

All patients who underwent tricuspid valve replacement between January 2014 and December 2015 were retrospectively reviewed. Patients having concomitant mitral or aortic valve surgery were excluded. These patients were divided into two groups: TAPSE >14 mm and TAPSE ≤14 mm. In-hospital outcomes were compared.

Results

A total of 26 patients with severe tricuspid valve regurgitation underwent tricuspid valve replacement. There were 5 males (19.2%) and 21 females (80.8%). The average age at operation was 54.77±9.61 years (range, 27–69 years). There were 16 patients in the TAPSE >14 mm group and 10 patients in the TAPSE ≤14 mm group. The BNP in the TAPSE >14 mm group was significant (TAPSE >14 mm 672.34±229.98 versus TAPSE ≤14 mm 1,054.79±684.69, P=0.03). The median cardiopulmonary bypass (CPB) time and red blood cell (RBC) transfusions in the two groups were not different. The need for prolonged ventilatory support (>48 h) in the two groups was also not different (TAPSE> 14 mm 91.2±12.31 vs. TAPSE ≤14 mm 39.00±36.80, P=0.46). Moreover, hospital stays were similar between the two groups. No differences were found in postoperative renal and respiratory complications.

Conclusions

It is important to determine the right ventricule function quantitatively. The TAPSE score is an important parameter that determines the cardiac index and right ventricle function. It should be used for the prediction of mortality and morbidity with all the other parameters as a whole.  相似文献   
63.
Fixed pericardial tissue is commonly used for commercially available xenograft valve implants, and has proven durability, but lacks the capability to remodel and grow. Decellularized porcine pericardial tissue has the promise to outperform fixed tissue and remodel, but the decellularization process has been shown to damage the collagen structure and reduce mechanical integrity of the tissue. Therefore, a comparison of uniaxial tensile properties was performed on decellularized, decellularized‐sterilized, fixed, and native porcine pericardial tissue versus native valve leaflet cusps. The results of non‐parametric analysis showed statistically significant differences (p < .05) between the stiffness of decellularized versus native pericardium and native cusps as well as fixed tissue, respectively; however, decellularized tissue showed large increases in elastic properties. Porosity testing of the tissues showed no statistical difference between decellularized and decell‐sterilized tissue compared with native cusps (p > .05). Scanning electron microscopy confirmed that valvular endothelial and interstitial cells colonized the decellularized pericardial surface when seeded and grown for 30 days in static culture. Collagen assays and transmission electron microscopy analysis showed limited reductions in collagen with processing; yet glycosaminoglycan assays showed great reductions in the processed pericardium relative to native cusps. Decellularized pericardium had comparatively low mechanical properties among the groups studied; yet the stiffness was comparatively similar to the native cusps and demonstrated a lack of cytotoxicity. Suture retention, accelerated wear, and hydrodynamic testing of prototype decellularized and decell‐sterilized valves showed positive functionality. Sterilized tissue could mimic valvular mechanical environment in vitro, therefore making it a viable potential candidate for off‐the‐shelf tissue‐engineered valvular applications.  相似文献   
64.

Essentials

  • Risk of venous thrombosis (VT) related to valve thickness and valvular reflux in unknown.
  • Venous valves and reflux were measured by ultrasonography in cases and controls aged 70+.
  • Risk of VT was associated with increased valve thickness and valvular reflux >1second.
  • Thickening of valves is a generic process: there was no difference between right and left legs.

Summary

Background

Increasing age is the strongest risk factor for venous thrombosis (VT). Increasing age has been related to a thickening of the venous valves and a decreased valvular function. The association between valve thickness and the risk of VT is not known.

Objectives

To assess the association between increased valve thickness and valve closure time (VCT) and the risk of VT.

Methods

Analyses were performed in the BATAVIA study, including 70 cases aged 70 + with a first VT and 96 controls. We performed an ultrasound examination of the valves in the popliteal veins. The valves were imaged with a 9 MHz linear probe using B‐mode ultrasonography. VCT was measured as an indicator for valve function using an automatic inflatable cuff. To estimate the risk of VT, valve thickness was dichotomized at the 90th percentile as measured in controls and VCT was dichotomized at 1 s.

Results

Mean valve thickness of controls was similar in the left (0.36 mm, 95% CI 0.34–0.37) and right (0.36 mm, 95% CI 0.35–0.38) leg. In 45 cases a valve was observed in the contralateral leg with a mean valve thickness of 0.39 mm (95% CI 0.36–0.42). Cases had an increased valve thickness compared with controls: mean difference 0.028 mm (95%CI 0.001–0.055). Valve thickness > 90th percentile increased the risk of VT 2.9‐fold. Mean VCT in controls was 0.38 s, in contralateral leg of cases 0.58 s. VCT > 1 s increased the risk of VT 2.8‐fold (95% CI 0.8–10.4).

Conclusions

Risk of VT was associated with increased valve thickness and valvular reflux of > 1 s.  相似文献   
65.
66.
An unusual case of aortic annular abscess is presented, in which the patient presented with features of gross tricuspid regurgitation. There was no direct involvement of the tricuspid valve. Tricuspid regurgitation disappeared following surgical repair of the annular abscess. The present case also illustrates the utility of trans-oesophageal echocardiography in establishing the diagnosis and planning surgical intervention.  相似文献   
67.
ObjectivesThe aim of this study was to assess cusp symmetry and coronary ostial eccentricity and its impact on coronary access following transcatheter aortic valve replacement (TAVR) using a patient-specific commissural alignment implantation technique.BackgroundTAVR implantation techniques to obtain neocommissural alignment have been introduced. The impact of cusp symmetry and coronary ostial eccentricity on coronary access after TAVR remains unknown.MethodsCardiac computed tomographic scans from 200 tricuspid aortic valves (TAVs) and 200 type 1 bicuspid aortic valves (BAVs) were studied. Cusp symmetry and coronary ostial eccentricity were assessed. In addition, the right coronary cusp/left coronary cusp and right coronary artery (RCA)/left coronary artery (LCA) ostia overlap views were calculated and compared.ResultsSevere cusp asymmetry (>135°) was more frequent in BAVs (52.5%) than in TAVs (2.5%) (P < 0.001), with the noncoronary cusp being the most common dominant cusp. The RCA ostium was found to be more often eccentric (>20°) than the LCA ostium (28% vs 6%, respectively; P < 0.001). Considering the right/left cusp overlap view, there was <20° deviation between the right coronary cusp–left coronary cusp centered line and the RCA-LCA centered line in 95% of all patients (TAV, 97%; BAV, 93%). The right/left cusp and coronary ostia overlap view differed by <10° and <20° fluoroscopic angulation in 75% and 98% of all cases, respectively.ConclusionsUsing the right/left cusp overlap view to obtain commissural alignment in TAVR is also an effective approach to implant one of the transcatheter heart valve commissures in the near center between both coronary ostia in most TAVs and type 1 BAVs. Preprocedural CT assessment remains crucial to assess cusp symmetry and coronary ostial eccentricity.  相似文献   
68.
Transesophageal echocardiography provides excellent images of mitral and aortic prostheses, due to its higher resolution and less interference from other cardiac structures. Since the introduction of transesophageal echocardiography, it has proved to be valuable for the evaluation of prosthetic heart valves. "Classic" indications include the evaluation of prosthetic valve endocarditis, the search for paravalvular abscesses, and the assessment of regurgitation in mechanical, especially mitral, prostheses. New technical developments such as biplane or multiplane transducers enhance the diagnostic capabilities of the technique. Transesophageal echocardiography can also have advantages in recognizing obstructive lesions such as thrombi or pannus, and help understand the complex morphology of prostheses in grafts. Transesophageal echocardiography should be considered a backup technique whenever transthoracic echocardiography, which always remains the primary approach, is inconclusive or negative in the presence of clinically suspected prosthetic valve malfunction.  相似文献   
69.
《JACC: Cardiovascular Imaging》2019,12(12):2373-2385
ObjectivesThis study sought to compare the prognostic value of 2-dimensional (2D) right ventricular (RV) speckle tracking (STE) against cardiac magnetic resonance (CMR) RV ejection fraction (EF) and feature tracking (FT) and conventional echocardiographic parameters on overall and cardiovascular (CV) survival in patients with heart failure with reduced EF (HFrEF).BackgroundPrior works showed that RV systolic function predicts prognosis in HFrEF. 2D RVSTE had recently been proposed as new echocardiographic method to evaluate RV dysfunction.MethodsA total of 266 patients with HFrEF (mean LVEF 23 ± 7%, 60 ± 14 years of age; 29% women) underwent RV function assessment using CMR and 2D echocardiography and were followed for a primary endpoint of overall death and secondary endpoint of CV death.ResultsAverage CMR-RVEF was 42 ± 15%, average STE RV global longitudinal strain (STE-RVGLS) was −18.0 ± 4.9%, and average CMR-FT-RVGLS was −11.8 ± 4.3%. After a median follow-up of 4.7 years, 102 patients died, 84 of a CV cause. RVEF, FT-RVGLS, tricuspid annulus plane systolic excursion (TAPSE), fractional area change (FAC), and STE-RVGLS were significant univariate predictors of overall and cardiac death. In multivariate Cox regression, age, ischemic etiology, diabetes, New York Heart Association functional class III to IV, and beta-blocker treatment were independent clinical predictors of overall mortality. CMR-RVEF (chi-square to enter = 3.9; p < 0.05), FT-RVGLS (chi-square to enter 3.7; p = 0.05), FAC (chi-square to enter 6.2; p = 0.02), and TAPSE (chi-square to enter = 4.1; p = 0.04) provided additional prognostic value over these baseline parameters, but the additional predictive value of STE-RVGLS (chi-square to enter = 10.8; p < 0.001) was significantly (p < 0.05) higher than the other tests. Additional hazard ratio to predict overall mortality was 2.5 (95% confidence interval [CI]: 1.6 to 3.9) for STE-RVGLS <−19%, 2.15 (95% CI: 1.34 to 3.43) for TAPSE >15 mm, 1.6 (95% CI: 1.02 to 2.49) for FAC >39%, 1.93 (95% CI: 1.25 to 2.99) for RVEF >41%, and 1.87 (95% CI: 1.10 to 3.19) for CMR-FT-RVGLS <−15%.Conclusions2D RVGLS provides strong additional prognostic value to predict overall and CV mortality in HFrEF, with higher predictive value than CMR-RVEF, CMR-FT-RVGLS, TAPSE, or FAC. This supports use of STE-RVGLS to identify higher-risk HFrEF patients.  相似文献   
70.
Right ventriculography with a preshaped catheter (J- or L-shaped) was evaluated in make the diagnosis of tricuspid regurgitation. Thirty normal subjects who did not have valvular disease showed no evidence of tricuspid regurgitation or premature ventricular contractions during injection except in one case. On the other hand, 24 patients with combined aortic and mitral valve disease showed mild to moderate tricuspid regurgitation in 11 patients and severe tricuspid regurgitation in eight patients. Only two patients developed frequent run of premature ventricular contraction during injection. Seven patients with severe tricuspid regurgitation were found to have severe tricuspid regurgitation during surgery. No evidence of tricuspid regurgitation was found In all six patients with isolated aortic valve disease. We can conclude that right ventriculography by the preshaped catheter improves the diagnostic accuracy of tricuspid regurgitation and a grading system of tricuspid regurgitation by angiography is proposed.  相似文献   
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