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11.
12.

Objectives

The aim of this study was to determine the prognostic value of pulmonary venous (PV) flow during MitraClip implantation.

Background

The clinical significance of PV flow information during MitraClip implantation is unknown.

Methods

A total of 300 patients who underwent MitraClip implantation and in whom the measurement of PV flow was completed using intraprocedural transesophageal echocardiography were retrospectively reviewed. The optimal threshold of the ratio of systolic velocity-time integral (Svti) to diastolic velocity-time integral (Dvti) ratio after MitraClip placement for major adverse cardiovascular events (all-cause death, redo MitraClip implantation, mitral valve surgery, and heart transplantation) during 12 months was assessed. The best cutoff ratio was 0.72. Patients were divided into 2 groups using this cutoff ratio (low Svti/Dvti, n = 91; high Svti/Dvti, n = 209).

Results

Following mitral regurgitation reduction by MitraClip placement, Svti increased in the both groups. The frequency of mitral regurgitation 3/4+ immediately after MitraClip implantation, at 1-month follow-up, and at 12-month follow-up was significantly higher in patients with low Svti/Dvti ratios than in those with high Svti/Dvti ratios (after MitraClip placement, 5.5% vs. 0%; p < 0.001; at 1 month; 26% vs. 5.2%; p < 0.001; at 12 months, 18% vs. 5.3%; p = 0.006). Major adverse cardiovascular events during 12 months were significantly higher in patients with low Svti/Dvti ratios than in those with high Svti/Dvti ratios (23% vs. 6.2%; p < 0.001). Multivariate analysis demonstrated that low Svti/Dvti ratio was significantly associated with major adverse cardiovascular events during 12 months after adjustment for age, baseline renal function, and mean transmitral pressure gradient (adjusted hazard ratio: 4.00; 95% confidence interval: 2.02 to 8.23; p < 0.001).

Conclusions

PV flow information in the catheterization laboratory immediately after MitraClip implantation predicted recurrent mitral regurgitation and worse long-term outcomes.  相似文献   
13.
Chronic consumption of processed food causes structural changes in membrane phospholipids, affecting brain neurotransmission. Here we evaluated noxious influences of dietary fats over two generations of rats on amphetamine (AMPH)-conditioned place preference (CPP). Female rats received soybean oil (SO, rich in n-6 fatty acids (FA)), fish oil (FO, rich in n-3 FA) and hydrogenated vegetable fat (HVF, rich in trans fatty acids (TFA)) for two successive generations. Male pups from the 2nd generation were maintained on the same supplementation until 41 days of age, when they were conditioned with AMPH in CPP. While the FO group showed higher incorporation of n-3 polyunsaturated-FA (PUFA) in cortex/hippocampus, the HVF group showed TFA incorporation in these same brain areas. The SO and HVF groups showed AMPH-preference and anxiety-like symptoms during abstinence. Higher levels of protein carbonyl (PC) and lower levels of non-protein thiols (NPSH) were observed in cortex/hippocampus of the HVF group, indicating antioxidant defense system impairment. In contrast, the FO group showed no drug-preference and lower PC levels in cortex. Cortical PC was positively correlated with n-6/n-3 PUFA ratio, locomotion and anxiety-like behavior, and hippocampal PC was positively correlated with AMPH-preference, reinforcing connections between oxidative damage and AMPH-induced preference/abstinence behaviors. As brain incorporation of trans and n-6 PUFA modifies its physiological functions, it may facilitate drug addiction.  相似文献   
14.
Objectives. This report evaluates the use of Gianturco coils to close large patent ductus arteriosus (PDAs) (≥3.5 mm) and describes transvenous delivery of 0.052-in. (0.132-cm) Gianturco coils.

Background. Coil closure of PDAs has become increasingly popular. However, the technique has significant limitations when used to close large PDAs. This report evaluates patient characteristics, PDA anatomy, hemodynamic variables, delivery technique and coil geometry to determine predictors of success.

Methods. Between January 1995 and January 1997, 16 of 118 patients undergoing catheterization for PDA closure were found to have large PDAs. Their median age and weight were 14 months (range 3 months to 43 years) and 8.5 kg (range 3.5 to 73), respectively. The mean PDA diameter was 4.3 mm (range 3.5 to 5.9). Closure of PDAs was attempted using transcatheter delivery of 0.038-in. (0.096-cm) and 0.052-in. coils. Differences in clinical, anatomic, hemodynamic and technical variables between successes and failures were compared.

Results. Eleven (69%) of 16 patients had successful closure of their PDA. Failures occurred only in patients <8 months of age with an indexed PDA diameter >7 mm/m and a pulmonary/systemic flow ratio ≥2.8:1. Use of 0.052-in. coils tended to reduce the incidence of embolization and the number of coils needed for closure.

Conclusions. Patients >8 months of age can have successful closure of large PDAs with currently available Gianturco coils. The 0.052-in. Gianturco coils can be used safely to close large PDAs in infants as small as 6 kg. Increased experience and improved coil design may improve closure rates of large PDAs in infants.  相似文献   

15.

Background and aims

Polyunsaturated fatty acids (PUFA) may play a role in the etiology of the metabolic syndrome (MetS). The aim of the study was to examine the associations of adipose tissue PUFA biomarkers with MetS among parents and children in Mesoamerica.

Method and results

We conducted a cross-sectional study among 468 parents and 201 children aged 7–12 y from the capital cities of Guatemala, El Salvador, the Dominican Republic, Honduras, Nicaragua, Panama, Costa Rica, and Belize, and Tuxtla Gutiérrez in Mexico. We measured PUFA biomarkers in gluteal adipose tissue by gas chromatography. In adults, MetS was defined according to the National Cholesterol Education Program's Adult Treatment Panel III definition. In children, we created an age- and sex-standardized metabolic risk score using abdominal circumference, the homeostasis model of insulin resistance, blood pressure, serum HDL cholesterol, and triglycerides. We estimated prevalence ratios of MetS and mean differences in metabolic score across quartiles of PUFA using multivariable-adjusted Poisson and linear regression models, respectively. Among adults, MetS was associated with low alpha-linolenic acid (ALA), high eicosapentaenoic acid (EPA), and low gamma-linolenic acid (GLA). It was linearly, positively associated with dihomo-gamma-linolenic acid (DGLA) and estimated Δ6-desaturase (D6D) activity. Among children, the metabolic score was positively associated with docosapentaenoic acid (DPA), DGLA, and D6D activity.

Conclusions

Among Mesoamerican adults, MetS prevalence is inversely associated with adipose tissue ALA and GLA, and positively associated with EPA, DGLA, and the D6D index. Among children, metabolic risk score is positively associated with DPA, DGLA, and the D6D index.  相似文献   
16.
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18.
ObjectivesThis study sought to examine left atrial (LA) mechanics and the prognostic impact of patients with echocardiographic findings of E/A ratio ≤0.75, deceleration time (DcT) of mitral E-wave >140 ms, but E/ε′ ≥10.BackgroundTraditional diastolic dysfunction (DD) grading system could not classify every patient into a specific group. We considered the group of patients with E/A ≤0.75, DcT >140 ms, but E/ε′ ≥10 (proposed new DD grade) as a new group in the DD grading system.MethodsA total of 1,362 consecutive patients were stratified according to the new DD grading system, and the LA volumes, strain, and strain rates were measured by 2-dimensional speckle-tracking analysis. All patients were followed up to determine cardiac death and major adverse cardiac events.ResultsAn E/A ≤0.75, DcT >140 ms, but E/ε′ ≥10 was observed in 227 patients (17%). LA volumes in patients with the new DD grade were between those of the impaired relaxation group and the pseudonormal group. LA strain of the new DD grade was similar to that of the pseudonormal group, whereas LA booster function was preserved as in the impaired relaxation group. During a mean follow-up of 3.0 ± 1.1 years, 25 patients had cardiac death and 61 had major adverse cardiac events. Event-free survival for major adverse cardiac events of the new DD grade was worse than that of the impaired relaxation group but similar to that of the pseudonormal group.ConclusionsThe new DD grade is frequently observed and has a prognosis similar to that of the pseudonormal group but significantly worse than that of the impaired relaxation group. However, LA booster function was maintained at the expense of LA volume enlargement. Thus, the new grade should be a distinct entity for routine DD grading.  相似文献   
19.
20.
Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy. The prevalence of phenotypic expression, in the absence of another systemic or cardiac disease causing increased left ventricular (LV) wall thickness, is estimated to be 1:500. The frequency of clinical presentation is far less, highlighting the need for a non-invasive diagnostic imaging tool. Echocardiography is readily available and allows for structural characterization and hemodynamic assessment of the hypertrophic heart and to screen patients at-risk for HCM, such as first degree relatives of affected individuals, and differentiate HCM from the athletic heart. Echocardiography can also be used to assess for anatomic abnormalities of the mitral valve apparatus that may exacerbate LV outflow track obstruction and to further risk stratify patients during exercise. Finally, echocardiography plays an integral role in guiding alcohol septal ablation procedures.  相似文献   
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