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21.
Rheumatic valvular affection is not an uncommon disease especially in the developing nations, but its association with dextrocardia is relatively rare. In the present day scenario, where mitral valve replacements far exceed the number of closed commissurotomies, a sound understanding of the anatomy, approach, and technique is vital vis-à-vis surgical management of these patients who do not have the finances for replacement of a severely stenotic valve or patients who may present in extremis. We present a case series of three such patients who underwent successful closed commissurotomies.  相似文献   
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Little is known about the influence of stenting versus balloon angioplasty on long-term outcomes (particularly mortality) after primary percutaneous coronary intervention (PCI). We evaluated 2,087 patients with ST-elevation myocardial infarction enrolled in various Primary Angioplasty in Myocardial Infarction (PAMI) trials in the United States, who underwent primary PCI. The main outcome was all-cause mortality at 5 years, obtained through the National Death Index. Of the 2,087 patients, stenting was performed in 692 (33%). The absolute difference in the hospital (2.2% vs 3.3%), 1-year (3.3% vs 5.2%), and 5-year (10% vs 13%) mortality rates favored patients receiving a stent versus conventional balloon therapy, with the difference increasing with time. A multivariate Cox model identified stent use (vs balloon alone) as an independent correlate of lower 5-year mortality (hazard ratio 0.60, 95% confidence interval 0.42 to 0.85). The absolute reduction in mortality was greatest in the highest risk group. In conclusion, compared with balloon angioplasty, stenting during primary PCI not only resulted in better angiographic and short-term outcomes, but also in a sustained beneficial effect on mortality at 5 years. These data support the routine use of coronary stenting in most patients undergoing primary PCI, when feasible.  相似文献   
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Background

Damage to the cardiac conduction system requiring permanent pacemaker (PPM) implantation is a known adverse outcome of transcatheter aortic valve replacement (TAVR). A permanent-temporary pacemaker (PTPM) is a device that involves an active-fixation lead attached to an external pulse generator taped to the skin. We reviewed the utility of PTPMs as a temporary bridge measure after TAVR in patients with conduction abnormalities that do not meet conventional criteria for PPM placement.

Methods

Between January 01, 2013 and December 31, 2015, we analyzed 67 patients who received PTPM after TAVR. Baseline demographics, comorbidities, type and size of the valve, pre-TAVR electrocardiograms (ECGs), post-TAVR ECGs at 1 day, 1 month, and 6 months, and pacemaker interrogation results were reviewed for each patient if available.

Results

The mean age of patients was 80.5?±?9.1 years. PTPM were placed for 2.3?±?2.4 days. Among these patients, 44.8% (n?=?30) received a PPM prior to discharge. Male gender (OR 2.84, 95% CI 1.05–7.69, p?=?0.05) and an increase in QRS duration post-TAVR (p?=?0.01) were associated with PPM placement. Pacemaker interrogation data of 11 patients with PPM revealed that 27% (n?=?3) had <?1% V-pacing requirements and <?10% A-pacing requirements.

Conclusions

In post-TAVR patients who develop conduction abnormalities that do not meet conventional PPM implantation indications, PTPM safely provides a time period for further assessment and may prevent unnecessary PPM implantation. Male gender and an increase in QRS duration post-TAVR are associated with PPM implantation. Additionally, some patients may recover from their conduction disturbances and demonstrate low pacemaker utilization.
  相似文献   
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BackgroundSacubitril/Valsartan (ARNI) has now class 1 recommendation for treatment of heart failure with reduced ejection fraction (HFrEF). It has been shown to reduce cardiovascular morbidity & mortality in Heart failure with reduced ejection fraction (HFrEF) and significant improvement in all echocardiographic parameters besides TEI index. Tei index is a marker of inflammation, myocardial cell metabolism and its contractile function has not been evaluated as a distinctive entity so we took up this study to evaluate the effects of ARNI on the LV functions using two dimensional (2D)ECHO parameters in Indian population and to assess TEI index for myocardial function.Methods256 patients with class II, III or IV HF and EF<40% were enrolled. 171(66.8%) were males and 85(33.2%) were females. Patients were evaluated at baseline, 6 and 12 months for LVEF, LV mass &,LVMPI. Drug was discontinued in 2 patients due to angioedema, in 5 patients due to acute kidney injury and in 2 patients due to hypotension. LV mass measurement done by linear echocardiographic method and Flow Doppler method used for TEI index calculation.ResultsBaseline parameters in 247 patients were mean EF = 26.33 ± 6.28%, mean LV mass = 270.84 ± 68.94 gm, mean Tei Index = 0.852 ± 0.22. ARNI use was associated with an average gradual increase in EF, from a mean baseline of 26.33 ± 6.28% to 33.88 ± 7.73%(p = 0.000001) after 1 year of treatment. There was a significant progressive reduction of 57.97 g/m2 in mean LV mass index after 1 year of treatment (p = 0.000001).TEI index showed significant reduction from baseline mean 0.85 ± 0.22 to 0.70 ± 0.12(p = 0.000001)after 1 year of treatment.ConclusionUse of ARNI as additive adjunct to standard care of treatment resulted in significant progressive decline in LV mass and increase in TEI index.  相似文献   
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Aging is associated with progressive deterioration in endothelial function. We hypothesized that losartan may represent a useful therapeutic strategy to ameliorate endothelial function in aged subjects. Eighteen healthy older subjects (mean age 75 +/- 3 years) were prospectively randomized in a double-blind, crossover fashion to receive either losartan 50 mg/day or placebo for 6 weeks. Subjects were switched to the opposite arm after a 2- week washout period. Flow-mediated dilation (FMD) in the brachial artery and plasma levels of vascular cell adhesion molecule-1, intercellular adhesion molecule (ICAM), moncocyte chemoattractant 1 protein, and E-selectin were measured in both arms at the beginning and end of the 6-week period. Losartan resulted in a 6-mm Hg decrease in systolic blood pressure (from 130 +/- 12 to 124 +/- 13 mm Hg), which was no different from placebo (132 +/- 12 to 127 +/- 13 mm Hg). FMD increased from 3.1 +/- 0.6% to 3.9 +/- 0.6% after losartan, and decreased from 3.3 +/- 0.3% to 2.4 +/- 0.6% after placebo (p = NS for both). In contrast, losartan reduced circulating concentrations of vascular cell adhesion molecule 1 (750 +/- 73 to 572 +/- 39), ICAM (405 +/- 26 to 196 +/- 10), and moncocyte chemoattractant 1 protein (560 +/- 56 to 423 +/- 35) (p <0.01 for all by analysis of variance), but not E-selectin. On univariate analyses, the strongest predictor of baseline endothelial function and change in FMD with losartan was low-density lipoprotein. There was a negative correlation between baseline endothelial function and change in FMD in response to losartan (r(2) = -0.75, p = 0.0003). Baseline ICAM levels alone significantly correlated with low-density lipoprotein cholesterol (r(2) = 0.54, p = 0.02) and weakly correlated with total cholesterol (r(2) = 0.47, p = 0.05). Thus, administration of losartan for a duration of 6 weeks has favorable effects on inflammatory markers in healthy older subjects, but does not alter peripheral conduit endothelial function.  相似文献   
29.
Herein, a facile in situ solvothermal technique for the synthesis of a CdMoO4/graphene composite photocatalyst is reported. Graphene oxide (GO) was synthesised by an improved Hummers'' method and was further used for the in situ synthesis of graphene via GO reduction and the formation of a CdMoO4 nanowire/graphene composite. The structural phase formation of tetragonal CdMoO4 was confirmed from X-ray diffraction measurements. The small nanoparticle assembled nanowires, prismatic microsphere morphology and crystalline nature of the synthesized material were investigated using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Due to its unique morphology and stability, the CdMoO4/graphene composite was used as a photocatalyst for H2O splitting. In comparison to pristine CdMoO4, the CdMoO4/graphene composite showed the best hydrogen evolution rate, i.e. 3624 μmole h−1 g−1, with an apparent quantum yield of 30.5%. The CdMoO4/graphene composite has a higher photocatalytic activity due to the inhibition of charge carrier recombination. H2 production measurements showed that the ternary semiconductor/graphene composite has enhanced photocatalytic activity for H2 generation.

Herein, a facile in situ solvothermal technique for the synthesis of a CdMoO4/graphene composite photocatalyst for hydrogen generation under natural solar light.  相似文献   
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