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861.
862.
ObjectiveTo examine the frequency and outcomes of patients requiring renal replacement therapy (RRT) early after left ventricular assist device (LVAD) implantation.Patients and MethodsWe examined use of in-hospital RRT and outcomes in consecutive adults who underwent continuous-flow LVAD implantation from February 15, 2007, through August 8, 2017. Logistic regression was used to examine predictors of RRT. The associations of RRT with outcomes were examined using Cox proportional hazards regression.ResultsOf 354 patients who underwent LVAD implantation, 54 (15%) required in-hospital RRT. Patients receiving RRT had higher preoperative Charlson Comorbidity Index values (median, 5 vs 4; P=.03), Model for End-Stage Liver Disease scores (mean, 19.0 vs 14.5; P<.001), right atrial pressure (mean, 19.1 vs 13.4 mm Hg; P<.001), and estimated 24-hour urine protein levels (median, 357 vs 174 mg; P<.001) and lower preoperative estimated glomerular filtration rate (eGFR) (median, 43 vs 57 mL/min; P<.001) and measured GFR using 125I-iothalamate clearance (median, 33 vs 51 mL/min; P=.001) than those who did not require RRT. Approximately 40% of patients with eGFR less than 45 mL/min/1.73 m2 and 24-hour urine protein level greater than 400 mg required RRT vs 6% with eGFR greater than45 mL/min/1.73 m2 and without significant proteinuria. Lower preoperative eGFR, higher estimated 24-hour urine protein level, higher right atrial pressure, and longer cardiopulmonary bypass time were independent predictors of RRT after LVAD implantation. Of patients requiring in-hospital RRT, 18 (33%) had renal recovery, 18 (33%) required outpatient hemodialysis, and 18 (33%) died before hospital discharge. After median (Q1, Q3) follow-up of 24.3 (8.9, 49.6) months, RRT was associated with increased risk of death (adjusted hazard ratio [HR], 2.86; 95% CI, 1.90-4.33; P<.001) and gastrointestinal bleeding (adjusted HR, 4.47; 95% CI, 2.57-7.75; P<.001).ConclusionIn-hospital RRT is associated with poor prognosis after LVAD. A detailed preoperative assessment of renal function before LVAD may be helpful in risk stratification and patient selection.  相似文献   
863.
Identifying the cause of unexplained cardiac arrest is critical for appropriate management of both survivors and their family members. Aborted cardiac arrests whose cause remains unknown following investigation with a surface ECG, echocardiogram, and coronary angiogram are deemed unexplained. Many of these unexplained arrests are felt to be secondary to concealed forms of cardiac channelopathies and latent or subtle cardiomyopathies. This recognition has led to evaluating a diagnostic role for a series of additional investigations, including advanced imaging, genetic testing, and provocative forms of testing, including sodium channel blockade and treadmill testing. Despite evidence of an improved diagnostic yield through their systematic usage, clinical guidelines have yet to endorse a formal algorithm delineating investigations that must be performed before assigning a label of idiopathic ventricular fibrillation, which has resulted in markedly variables thresholds for concluding this diagnosis. Debate remains regarding the need for an invasive electrophysiology study among these patients, though identification of arrhythmic culprits requiring intracardiac electrograms for diagnostic confirmation have suggested a potential role when an initial comprehensive evaluation is unrevealing. Although progress is being made, the sizeable portion of arrests that remain unexplained despite completion of a comprehensive evaluation highlights an ongoing need for further research and additional tools to help unravel the ongoing mysteries of these near fatal events.  相似文献   
864.
865.
BACKGROUND: In non-Asiatic population, apical hypertrophic cardiomyopathy represents 1% to 2% of hypertrophic cardiomyopathies. The presence of an apical ventricular aneurysm occurs in 1% of patients with the apical variant of hypertrophic cardiomyopathy. METHODS AND RESULTS: We present two patients with hypertrophic cardiomyopathy, both illustrating an early diastolic paradoxic jet flow between the apex and the middle area of ventricle. Such paradoxic flow is possibly due to the coexistence of mid-chamber obliteration and segmental wall motion abnormalities at the apex. The incidence and clinical significance of this flow pattern is still to be clarified.  相似文献   
866.
867.
糖尿病肾病患者肾小球基因表达谱及其与病情进展的关系   总被引:4,自引:5,他引:4  
目的 :研究糖尿病肾病 (diabeticnephropathy ,DN)患者肾小球基因表达谱与正常人之间的差异 ,及其在DN病程进展中的变化。  方法 :选择分别处于微量白蛋白尿期 ,临床蛋白尿期及伴有肾功能损害期的 3例DN患者 ,并以性别、年龄与患者匹配的 2例正常供肾组织作为对照。首次应用显微微分离法获取肾活检标本中的肾小球 ,进行肾小球细胞数目扩增 ,利用AffymetrixU133A基因芯片技术检测其基因表达谱的变化 ,以生物信息学工具作聚类分析。  结果 :与正常对照组相比 ,DN患者肾小球内表达水平显著上升或下降的基因共有 182条(P <0 0 1)。聚类分析将显著差异表达基因群分为表达水平显著升高、表达水平下降和持续性显著下降三个特殊亚群。功能分析发现 ,DN患者肾小球基因表达谱的变化突出表现在某些与细胞内异常糖和脂质代谢、细胞增殖、细胞外基质合成和细胞因子相关基因上 ,特别是脂质代谢相关基因。部分基因的表达变化与DN病情进展有一定相关性 ,存在随病情进展表达水平逐渐增加、在DN病程早期应答和随病情进展表达水平逐渐下降的三组基因。未发现转化生长因子 β1在DN患者肾小球细胞内mRNA表达水平呈现显著变化。  结论 :与正常人相比 ,DN患者肾小球基因表达谱的变化突出表现在某些与细胞内异常糖和脂质代谢  相似文献   
868.
OBJECTIVE: To assess the effect of partial left ventriculectomy (PLV) on estimate of left ventricular end systolic elastance (Ees), arterial elastance, and ventriculoarterial coupling. PATIENTS: 11 patients with idiopathic dilated cardiomyopathy before and two weeks after PLV, and 11 controls. INTERVENTIONS: Single plane left ventricular angiography with simultaneous measurements of femoral artery pressure was performed during right heart pacing before and after load reduction. RESULTS: PLV increased mean (SD) Ees from 0.52 (0.27) to 1.47 (0.62) mm Hg/ml (p = 0.0004). The increase in Ees remained significant after correction for the change in left ventricular mass (p = 0.004) and end diastolic volume (p = 0.048). As PLV had no effect on arterial elastance, ventriculoarterial coupling improved from 3.25 (2.17) to 1.01 (0.93) (p = 0.017), thereby maximising left ventricular stroke work. CONCLUSION: It appears that PLV improves both Ees and ventriculoarterial coupling, thus increasing left ventricular work efficiency.  相似文献   
869.
BACKGROUND AND AIM: Abnormal myocardial acoustic properties have been reported in patients with idiopathic dilated cardiomyopathy (IDC). The aim of this study was to investigate the relationship between quantitative ultrasonic textural alterations of myocardium and clinical outcome in IDC. METHODS: Baseline clinical and echocardiographic variables were obtained from 28 patients with IDC. By using a videodensitometric approach, quantitative myocardial texture analysis was performed on images obtained from septum and posterior wall (PW). Cyclic variation (CV) index of mean gray level (MGL) was calculated according to the formula: (MGLdiast-MGLsyst)/MGLdiastx100. All patients were followed for an average of 11+/-5 months for the occurrence of cardiac death or repeated hospitalization due to worsening of heart failure. RESULTS: During follow-up, 10 patients experienced cardiac events (6 cardiac deaths and 4 heart failure events). The CV indexes of both septum and PW were significantly lower in patients with cardiac events than those of event free patients (6.8+/-9.6% vs. 13.6+/-8.2%, P<0.05 and 5.3+/-6.4% vs.15.7+/-7.2% P<0.001, respectively). Univariate analysis defined the following variables as predictors of outcome: PW-CV index (chi2=13.0, P=0.0003), transmitral E/A ratio (chi2=12.5, P=0.0004), symptom status (chi2=8.7, P=0.003), and septum-CV index (chi2=4.7, P=0.03). Multivariate stepwise regression analysis showed that the PW-CV index (chi2=7.5, P=0.006) and E/A ratio (chi2=6.5, P=0.01) were the independent predictors of outcome. The event-free survival rate of patients with PW-CV index <11% was significantly lower than those with an index > or = 11 (35.7% vs. 92.8%, P=0,001). CONCLUSION: The assessment of severely depressed CV index provides valuable prognostic information in patients with IDC.  相似文献   
870.
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