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991.
Dopexamine hydrochloride (Dopacard®) is a new syntheticcatecholamine compound, which possesses potent ß2-adrenergicand D A 1-dopaminergic agonistic properties. It is free of a-adrenergicactivity, has no ß1-adrenergic activity and is lesspotent at D A2-dopaminergic receptors than dopamine. In thepresent study the acute haemodynamic effects of dopexamine hydrochloridewere compared to those of dobutamine and nitroprusside in 12patients with idiopathic congestive cardiomyopathy in an opencrossover study. With dopexamine hydrochloride, there were dose-dependentincreases from control in cardiac output and stroke volume,decreases in blood pressure, right and left atrial pressure,systemic vascular resistance and pulmonary vascular resistanceand little change in heart rate. Similar effects were seen withnitroprusside, apart from a marked increase in heart rate, andwith dobutamine, except that systolic aortic blood pressureincreased and there was no change in diastolic or mean pressureor pulmonary artery systolic pressure. In general, dopexamine hydrochloride produced effects betweenthose produced by the other two treatments. This suggests thatdopexamine with its combined vasodilator and inotropic actionhas a desirable cardiovascular profile with advantages overthe ß1-receptor aganist dobutamine and the pure vasodilatorsodium nitroprusside.  相似文献   
992.
《JACC: Cardiovascular Imaging》2019,12(10):1930-1942
ObjectivesThe association of left ventricular global longitudinal strain (LV-GLS) with clinical outcomes in patients with hypertrophic cardiomyopathy (HCM) has been examined in multiple studies. The authors conducted a systematic review aimed at summarizing and critically appraising the current evidence.BackgroundHCM is a common genetic cardiovascular disease with an estimated prevalence of 1 in 500 patients. LV-GLS derived from speckle tracking echocardiography is a sensitive noninvasive method of assessing regional left ventricular function. Several studies have suggested association of abnormal LV-GLS with outcomes in HCM patients.MethodsA computerized literature search of all English language publications in the PubMed and EMBASE databases was made looking at all randomized and nonrandomized studies conducted on patients with HCM where association of LV-GLS with clinical outcomes was studied. We then manually searched the reference lists of included articles. The Preferred Reporting Items for Systematic reviews and Meta-Analyses statement (PRISMA) of reporting systematic reviews was used.ResultsOur search yielded a total of 14 observational studies published between 2009 and 2017 with a total of 3,154 patients with HCM. Eleven of the 14 studies included a composite cardiac outcome which included mortality as their primary outcome of interest and 3 of the 14 studies looked at association of LV-GLS with ventricular arrhythmias and/or implantable cardiac defibrillator discharge. We noted wide variability in inclusion, methodology, follow-up, and consequently effect estimates, which was not conducive to performing a meta-analysis. However, despite the variation, all studies revealed a degree of association of abnormal LV-GLS with poor cardiac outcomes.ConclusionsOur systematic review of more than 3000 HCM patients suggests an association of abnormal LV-GLS with adverse composite cardiac outcomes and ventricular arrhythmias.  相似文献   
993.
ObjectivesThe aim of this study was to characterize left atrial (LA) pathology in explanted hearts with transthyretin amyloid cardiomyopathy (ATTR-CM); LA mechanics using echocardiographic speckle-tracking in a large cohort of patients with ATTR-CM; and to study the association with mortality.BackgroundThe clinical significance of LA involvement in ATTR-CM is of great clinical interest.MethodsCongo red staining and immunohistochemistry was performed to assess the presence, type, and extent of amyloid and associated changes in 5 explanted ATTR-CM atria. Echo speckle tracking was used to assess LA reservoir, conduit, contractile function, and stiffness in 906 patients with ATTR-CM (551 wild-type (wt)-ATTR-CM; 93 T60A-ATTR-CM; 241 V122I-ATTR-CM; 21 other).ResultsThere was extensive ATTR amyloid infiltration in the 5 atria, with loss of normal architecture, vessels remodeling, capillary disruption, and subendocardial fibrosis. Echo speckle tracking in 906 patients with ATTR-CM demonstrated increased atrial stiffness (median [25th-75th quartile] 1.83 [1.15-2.92]) that remained independently associated with prognosis after adjusting for known predictors (lnLA stiff: HR: 1.23; 95% CI: 1.03-1.49; P = 0.029). There was substantial impairment of the 3 phasic functional atrial components (reservoir 8.86% [5.94%-12.97%]; conduit 6.5% [4.53%-9.28%]; contraction function 4.0% [2.29%-6.56%]). Atrial contraction was absent in 22.1% of patients whose electrocardiograms showed sinus rhythm (SR) “atrial electromechanical dissociation” (AEMD). AEMD was associated with poorer prognosis compared with patients with SR and effective mechanical contraction (P = 0.0018). AEMD conferred a similar prognosis to patients in atrial fibrillation.ConclusionsThe phenotype of ATTR-CM includes significant infiltration of the atrial walls, with progressive loss of atrial function and increased stiffness, which is a strong independent predictor of mortality. AEMD emerged as a distinctive phenotype identifying patients in SR with poor prognosis.  相似文献   
994.
目的探讨高脂血症对胰岛素抵抗时多脏器损伤机理及防治措施。方法采用高脂饮食诱发高脂血症复制胰岛素抵抗Beagle犬模型,随机分为高脂组(n=4)、复方丹参滴丸组(n=4)和对照组(n=4)。饲养40周后取肾、肝、脑、心肌、胰腺等组织标本,通过H-E、甲苯胺蓝、丙二醛等免疫组化,苏丹和锇酸脂肪染色等多种染色,观察组织病理改变和脂质氧化、脂质沉积。结果高脂组,肝、脑尤其肾的病理损伤较其他脏器重。肾小球硬化,髓质肾小管上皮细胞内和管腔内大量脂质沉积并脂质氧化。肝细胞、小叶间胆管上皮细胞和脑神经元内发生脂质沉积和氧化,胶质细胞增生,微动脉硬化。复方丹参滴丸明显减轻脂质沉积和脂质氧化。结论犬胰岛素抵抗模型的组织和细胞内脂毒性作用可能是引起肾、肝、脑、血管等脏器损伤的重要机制。复方丹参滴丸通过调脂和抗氧化作用保护脏器。  相似文献   
995.
996.
Diabetes mellitus is a growing epidemic with a prevalence among patients with heart failure (HF) approaching 30%. Diabetes worsens the prognosis of HF, and the pathophysiology is complex and multifactorial. Early detection of subtle alterations in cardiac function by modern tools, such as Doppler echocardiography or brain natriuretic peptide dosage, is thus important in these patients. All drugs known to be effective in HF with systolic dysfunction are also effective in patients with diabetes. Angiotensin-converting enzyme inhibitors and angiotensin II receptor antagonists also seem particularly useful. Overall, however, little is known about the treatment of diabetic patients with HF, especially in case of preserved systolic function. Ongoing and future trials should help to determine the best treatment for these patients with or without associated diabetes. This review assesses the relationships between diabetes mellitus and HF and discusses the various medical strategies.  相似文献   
997.
Abstract
Background: Established renal failure is a known cause of anaemia. However, the association between more modest levels of renal impairment and anaemia is unclear.
Aims: The aim of the present study was to investigate the association between mild renal impairment and anaemia in the general population.
Methods: A population-based, cross-sectional study was conducted in the general community in an urban area of the Blue Mountains, just west of Sydney, Australia. The study included 3222 people aged ≥49 years (mean age 65 years). Serum creatinine and haemoglobin were measured using standard laboratory techniques. Creatinine clearance was estimated from serum creatinine, body weight, sex and age.
Results:  Two hundred and seventy subjects (8.4%) had serum creatinine levels ≥125 µmol/L and estimated ­creatinine clearances were <0.84 mL/s (50 mL/min) in 894 subjects (27.7%) and <0.50 mL/s (30 mL/min) in 120 subjects (3.7%). There was a strong association between reduced renal function and anaemia. Compared to those with serum creatinine <125 µmol/L, the age-adjusted relative risk (RR) of anaemia in women (haemoglobin <12.0 g/dL) with serum creatinine ≥125 µmol/L was 5.5 (95% confidence interval (CI) 2.9−10.7) and the RR of anaemia in men (haemoglobin < 13.0 g/dL) was 3.1 (95% CI 1.6−6.0). Estimated ­creatinine clearance <50 mL/min was associated with a three-fold increased risk of anaemia in women and a five-fold increased risk in men.
Conclusions: The results of the present study suggest that even modestly impaired renal function is associated with anaemia in older men and women. The possibility of renal impairment should be considered in the diagnosis and management of anaemia in people aged>50 years. (Intern Med J 2004; 34: 20−23)  相似文献   
998.
Central illustration. Time of occurrence and outcome of cardiovascular disorders in patients (pts) with congenital portosystemic shunt (CPSS). Patients with normal anatomy and those with congenital heart disease (CHD) were distinguished. Heart failure (HF) was the main symptom in both the prenatal and neonatal periods, whereas portopulmonary hypertension (PPH) and hepatopulmonary syndrome (HPS) represented the major concerns beyond the first months of life. CV: cardiovascular; NAS: no additional symptoms; PH: pulmonary hypertension; RD: respiratory distress. aFetal diagnosis of CPSS. bNeonatal diagnosis of CPSS. cDiagnosis of CPSS > 1 month of age
  相似文献   
999.
Acute renal failure (ARF) requiring hemodialysis after percutaneous coronary interventions (PCI) is a serious complication with poor prognosis. Hemodialysis-induced hypotension may have deleterious cardiovascular effects, especially in high-risk patients. Ultrafiltrate removal and simultaneous fluid replacement with a solution similar to plasma for high-volume controlled hydration can be obtained with hemodynamic stability by continuous veno-venous hemofiltration (CVVH). We prospectively assessed the safety and effectiveness of percutaneous CVVH (Y-shaped double-lumen catheter, circuit originating from and terminating in the femoral vein) in 33 consecutive patients (23 men and 10 women; mean age, 69 +/- 9 years) who, after PCI, developed oligo-anuric ARF, associated in 20 of them with congestive heart failure. All patients received a concomitant infusion of furosemide (500-1000 mg/day) and dopamine (2 microg/kg/min). During CVVH, the average fluid volume replacement and body fluid net reduction were 1000 +/- 247 and 75 +/- 48 ml/hr, respectively. Treatment with CVVH continued for 4.7 +/- 2.7 days and corrected fluid overload in all cases. No patient experienced systemic hypotension or hypovolemia. Diuresis recovered in 32 (97%) patients, who showed a parallel improvement of renal function parameters. One patient required chronic dialysis. In-hospital and 1-year mortality was 9.1% and 27.3%, respectively. In conclusion, our data indicate that CVVH is a safe and effective therapy of radiocontrast-induced ARF following PCI. It temporarily replaces renal function without deleterious cardiovascular effects, allowing the kidney to recover from the nephrotoxic injury. However, despite promising early results, large randomized trials are required to define the role of CVVH in ARF after PCI.  相似文献   
1000.
BackgroundChronic renal failure (CRF) referred to chronic progressive renal parenchymal damage caused by various causes, with metabolite retention and imbalance of water, electrolyte, and acid‐base balance as the main clinical manifestations. Secondary hyperparathyroidism (sHPT) was a common complication in maintenance hemodialysis patients with CRF. Nuclear factor IB (NFIB) was a newly found tumor suppressor gene in various cancers. The present study aimed to illustrate the role of NFIB in sHPT clinical diagnosis and treatment response.MethodsA retrospective, case‐control study, including 189 patients with sHPT and 106 CRF patients without sHPT, compared with 95 controls. Serum NFIB and 1,25(OH)2D3 levels were measured by RT‐qPCR and ELISAs, respectively. ROC analysis was conducted to verify the diagnostic value of NFIB in sHPT. Spearman''s correlation analysis was conducted to verify the association between NFIB and bone mineral density (BMD) scores. After 6 months of treatment, the variance of NFIB and 1,25(OH)2D3 in different groups was recorded.ResultsThe expression of NFIB was significantly lower in serum samples from sHPT and non‐sHPT CRF patients, compared to controls. Clinicopathological information verified sHPT was associated with NFIB, parathyroid hormone (PTH), serum calcium, serum phosphorus, time of dialysis, and serum 1,25(OH)2D3 levels. Spearman''s correlation analysis illustrated the positive correlation between NFIB levels and BMD scores. At receiver operator characteristic (ROC) curve analysis, the cutoff of 1.6508 for NFIB was able to identify patients with sHPT from healthy controls; meanwhile, NFIB could also discriminate sHPT among CRF patients as well (cutoff = 1.4741). Furthermore, we found that during 6 months of treatment, NFIB levels were gradually increased, while PTH and serum P levels were decreased.ConclusionsSerum NFIB was a highly accurate tool to identify sHPT from healthy controls and CRF patients. Due to its simplicity, specificity, and sensitivity, this candidate can be proposed as a first‐line examination in the diagnostic workup in sHPT.  相似文献   
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