Hemodynamic effects of arteriovenous fistula in end-stage renal failure

Hemodynamic parameters using Swan Ganz catheter were studied in 17 patients with end stage renal disease. The acute effects of radiocephalic AV fistula on the hemodynamic parameters were studied at 24 hours of surgery. The chronic effects were studied in 8 of these patients at 6 weeks of arteriovenous (AV) fistula. The AV fistula matured in 3 to 4 weeks time and blood flow was sufficient for hemodialysis (400 mL/min). Patients with chronic renal failure had normal or high normal hemodynamic parameters. Six weeks after the AV fistula, the cardiac index and the stroke volume index slightly increased along with a significant increase in systolic and mean systemic arterial pressure. None of the patients had significant increase in cardiac filling pressures. Although there was some fall in systemic vascular resistance index and rise in cardiac index and stroke volume index, these changes were physically small and unlikely to put any extra hemodynamic load. Thus, AV fistula in dialysis patients is not an appreciable cause of circulatory or pulmonary congestion.     

Effect of radial artery calcification on survival of arteriovenous fistula and the patients in end-stage renal disease patients

Objective To investigate the effect of radial artery calcification (RAC) on survival of arteriovenous fistula (AVF) and the patients in end-stage renal disease. Methods Adult ESRD patients undergoing AVF surgery between January 2013 and January 2016 at the Eighth Affiliated Hospital of Sun Yat-sen University were enrolled in this study. The clinical and biochemical data were collected. Segment of radial artery were obtained from the operation of AVF. RAC at the site of anastomotic were observed by alizarin red S and hematoxylin and eosin staining. According to RAC, the patients were divided into calcification group and non-calcification group. Kaplan-Meier analysis was performed to analyze the survival rates of the two groups, and Cox proportional hazards regression model was used to estimate the risk factors of AVF dysfunction and all-cause mortality in ESRD patients. Results Among 180 cases of ESRD patients, 38 cases (21.1%) were developed RAC at the site of anastomotic in different degrees. Compared with the non-calcification groups, the calcification groups had a longer dialysis vintage, a higher proportion of diabetes and higher level of HbAlc (all P﹤0.05). Binary logistic regression analysis showed that dialysis vintage＞5 years and diabetics were two independent risk factors of RAC at the site of anastomotic. Kaplan-Meier survival analysis demonstrated that there were no statistical differences between two groups in AVF survival ( χ2=0.009, P=0.926). Calcification group had higher all-cause mortality than non-calcification groups ( χ2=9.809, P=0.002). Multivariate Cox regression analysis demonstrated that homocysteine was independent risk factor for AVF dysfunction (HR=1.027, 95%CI: 1.003-1.051, P=0.027). Age was independent risk factor for all-cause mortality (HR=1.078, 95%CI: 1.035-1.122, P=0.000). Conclusions Dialysis vintage＞5 years and diabetes were two independent risk factors of RAC at the site of anastomotic in ESRD patients. RAC at the site of anastomotic had no effect on AVF survival, but increased all-cause mortality.     

终末期肾病血液透析患者血浆COMP表达与动静脉内瘘失功及预后的相关性研究

目的 检测终末期肾病(end-stage renal disease,ESRD)血液透析患者血浆软骨寡聚基质蛋白(cartilage oligomeric matrix protein,COMP)表达,并分析COMP与动静脉内瘘(arteriovenous fistula,AVF)失功及预后的相关性.方法 选取2015...     

动静脉内瘘关闭修复术在肾移植中的应用

目的：探讨动静脉内瘘关闭修复术对心功能的影响,以扩大同种异体肾移植适应证。方法：对８例长期血液透析反复出现心力衰竭者在肾移植前５个月行动静脉内瘘关闭修复术。结果：心腔恢复正常７例,心腔内径在正常上限１例。肾移植成功６例,肝功能衰竭死亡１例,自发性肾破裂作肾切除１例。结论：肾移植前先行动静脉内瘘关闭修复术有利于改善患者心、肺功能,扩大手术适应证,减少并发症,为肾移植创造有利条件。     

A novel factor for primary arteriovenous fistula failure: hyperinsulinism

Introduction: Dysfunction of vascular access is an important reason of morbidity for dialysis patients and it is a major factor affecting the economical burden of hemodialysis. The preferred type of vascular access is creation of an arteriovenous fistula (AVF). However, the problem of fistula maturation rate is still a challenge. Herein, we tried to search the role of hyperinsulinism and insulin resistance as a new predictor of primary AVF failure (pAVFF) that may be a cause of intimal damage.

Methods: We included 119 patients (73 male and 46 female) with a diagnosis of end-stage renal disease (ESRD) who had undergone an AVF operation by a vascular surgeon. The AVF was examined for presence of thrill on the first postoperative day. A successful cannulation with two fistula needles with a blood flow of 250?mL/min for at least one complete dialysis session, after 4 weeks of AVF surgery was defined as functioning access. Insulin resistance in our patients was determined by the standard homeostasis model assessment (homa-IR). A logistic-regression analysis was performed to investigate the independent factors related with pAVFF.

Findings: Detection of pAVFF occurred in 27 (22.7%) patients. The presence of thrill, amount of daily proteinuria, insulin levels, homa-IR, and serum albumin levels were found to be significantly different between patients with fistula failure and those without pAVFF. The logistic-regression analysis of preoperative factors revealed the following OR (odds ratio) and 95% CI values: homa-IR 1.205 (1.063–1.366) (p?=?0.004), serum albumin 0.398 (0.178–0.892) (p?=?0.025), and the amount of daily proteinuria 1.307 (1.012–1.688) (p?=?0.041). Even after addition of the presence of postoperative thrill on AVF, which was a postoperative strong clinical factor to the analysis, mean homa-IR and mean serum albumin continued to be independent predictors of pAVFF.

Discussion: Insulin resistance or hyperinsulinism may be a significant cause of pAVFF, which emphasizes the role of endothelium in fistula dysfunction.     

Hypocalcemic heart failure in end-stage renal disease

A 37-year-old woman presented with hypocalcemic heart failure complicating end-stage renal disease. Heart failure persisted despite conventional therapy but improved after correction of hypocalcemia. Continuous monitoring of left ventricular function by radionuclide study during calcium replacement showed dramatic improvement. Our case showed that hypocalcemia could be a rare but reversible cause of frank heart failure in uremic patients.     

Management of coronary artery disease in end-stage renal disease

Despite a substantial number of patients with end-stage renal disease who have coronary artery disease, the comparative effectiveness of revascularization procedures such as coronary artery bypass grafting and percutaneous coronary intervention remain unclear. Innovations in the field of coronary artery revascularization and concomitant changes in the standard of practice have improved outcomes in general. However, meaningful clinical decision-making remains difficult because it requires clinicians to extrapolate evidence derived from studies in the general population to patients with kidney disease for whom there is limited information from intervention trials. In non-randomized studies, this high-risk population for cardiovascular morbidity and mortality appear to derive substantial benefits from coronary revascularization. However, specific treatment decisions are often made based upon individual circumstances and contexts that are not well captured in these studies. This article reviews the available evidence, and its limitations, for deciding between various revascularization strategies for patients with end-stage renal disease. Several considerations that arise while making such decisions are discussed.     

Evaluation and treatment of coronary artery disease in patients with end-stage renal disease

Evaluation and treatment of coronary artery disease in patients with end-stage renal disease. Patients with end-stage renal disease (ESRD) are at increased risk of death from coronary artery disease (CAD). The metabolic milieu that results from renal dysfunction appears to accelerate the atherosclerotic process by decades in patients with ESRD. The extremely high prevalence of atherosclerosis in patients with ESRD mandates risk factor identification and treatment. Traditionally, CAD in this patient population has been treated conservatively. Analysis of large databases has highlighted the scope and complexity of this problem; nonetheless, there is a paucity of randomized, controlled trials of CAD in patients with ESRD. In this paper the following issues related to evaluation and treatment of patients with chronic kidney disease are addressed: (1) optimal CAD risk management; (2) evaluation for CAD in patients with ESRD, including the identification of coronary calcification; (3) treatment of CAD with medical therapy and revascularization; (4) relative merits of percutaneous coronary intervention versus bypass surgery. In general, an aggressive approach to medical management of CAD is warranted, even in the setting of subclinical CAD. A low threshold for diagnostic testing should be employed in patients with ESRD. When significant CAD is identified, ESRD patients appear to benefit more from revascularization compared to conservative medical management. Thus, if clinically reasonable, patients with ESRD and CAD should be managed aggressively to improve survival and reduce the incidence of future cardiac events.     

Angiographic progression of coronary artery disease in patients with end-stage renal disease.

BACKGROUND: Patients with end-stage renal disease have an increased risk of developing coronary artery disease (CAD). The cardiovascular mortality of dialysis patients is 10-15 times higher compared with the general population. The aim of our study was to evaluate the morphological progression of coronary arteriosclerosis in this cardiovascular high-risk group by visual assessment and quantitative coronary angiography. Methods and results. In 26 patients with chronic renal failure (age, 47+/-11 years; 15 male; duration of dialysis, 23+/-25 months) the severity of CAD and degree of coronary stenoses were assessed in two coronary angiograms after a mean follow-up interval of 30+/-15 months (12-60). Baseline angiography revealed CAD in 13/22 patients (59%). The second angiography was performed as screening procedure prior to renal transplantation (n=20) and/or as follow-up angiography after coronary angioplasty (n=10). Visual assessment showed a progression defined by the development of haemodynamically relevant stenosis of >50% luminal diameter in 13 patients. Quantitative angiographic evaluation was performed in a total of 45 segments showing >25% narrowing at the second angiogram. A progression (>15% luminal reduction) was found in 17 of 45 segments, a new lesion (initial luminal diameter <20%) was detected in nine segments, resulting in progression or new lesion in 16 patients (62%). Patients with or without progression did not differ in age, duration of dialysis treatment, number of cardiovascular risk factors, or serum total cholesterol and fibrinogen levels. After percutaneous transluminal coronary angioplasty (PTCA) a restenosis was seen in seven of 16 primarily successfully dilated segments. After the second angiography, myocardial revascularization was performed in eight patients (1 PTCA, 7 coronary artery bypass graft). CONCLUSIONS: Patients with end-stage renal disease have a high prevalence of CAD. In line with the clinical course, CAD patients on maintenance dialysis undergo rapid angiographic progression of CAD, which results in a high rate of subsequent myocardial revascularizations.     

Diagnostic tools and management strategies for coronary artery disease in patients with end-stage renal disease

Patients with renal disease often have coexistent coronary artery disease (CAD). The 5-year survival rates are < 50% and cardiovascular disease accounts for nearly half of the deaths in patients with end-stage renal disease (ESRD) on maintenance dialysis. Renal disease is often caused by hypertension or diabetes mellitus, both very strong risk factors for the development of CAD. Other patients develop hypertension after the onset of their renal disease. These coexistent diseases partially contribute to the increased incidence of CAD in the renal patient. Managing physicians must maintain a high index of suspicion and interpret the results of diagnostic studies with this high pretest probability in mind. Consideration should be given for screening for the presence of ischemic heart disease in patients with ESRD and no symptoms, especially if being considered as renal transplant recipients. It remains most important to adequately treat the associated risk factors and specifically, aggressively control the blood pressure. This report discusses the known and suspected reasons for the highly associated coexistent CAD, methods for diagnosing and risk-stratifying CAD, and renal-specific guidelines for appropriate treatment.     

Aortic and large artery compliance in end-stage renal failure

Pulse wave velocity (PWV) was measured in the aorta, right leg and arm of 90 control subjects (CS) and 92 hemodialysis patients (HD) of the same age and mean arterial pressure (MAP). Blood chemistry, including blood lipids, and echographic dimensions of the aorta, were measured in all subjects. Presence of aortic calcification was evaluated by abdominal X-ray and echography. Whereas femoral and brachial PWV were only slightly increased in HD (P less than 0.05), the aortic PWV was significantly elevated (1113 +/- 319 cm/sec) in comparison with CS (965 +/- 216 cm/sec; P = 0.0016). Aortic diameters were larger in HD, both at the root of aorta (32.7 +/- 4 vs. 28.2 +/- 2.8 mm; P less than 0.0001) and aortic bifurcation (16.9 +/- 3.1 vs. 14.6 +/- 2.2 mm; P less than 0.0001). Although the MAP was similar in HD (109.9 +/- 19.3 mm Hg) and CS (110.2 +/- 17.2 mm Hg), the pulse pressure was significantly increased in HD patients (76.6 +/- 23.7 vs. 63.9 +/- 22 mm Hg; P = 0.007). In the two populations, aortic PWV was found to increase with age (P less than 0.0001) and MAP (P less than 0.0001). The presence of aortic calcification showed only a borderline relationship with the increase in aortic PWV (P = 0.050 in CS and P = 0.069 in HD). As change in PWV is directly related to change in distensibility, and the aortic diameters were increased in HD, these results indicate that aortic wall compliance is decreased in HD, resulting in an increase in the pulsatile component of arterial pressure.(ABSTRACT TRUNCATED AT 250 WORDS)     

Intravenous N-acetylcysteine during hemodialysis reduces asymmetric dimethylarginine level in end-stage renal disease patients

AIM: Cardiovascular disease is the main cause of mortality in chronic kidney disease patients. Moreover, uremic patients are in a pro-oxidant state and show an increase in asymmetric dimethylarginine (ADMA) levels due to inhibition of the enzyme dimethylarginine dimethylaminohydrolase (DDAH). Asymmetric dimethylarginine per se seems responsible for a 52% increase in the risk of death and for a 34% increase in the risk of cardiovascular events in dialysis patients. N-acetylcysteine (NAC) is a thiol molecule that has direct and indirect antioxidant effects which decrease reactive oxidant species and increase the bioavailability of the DDAH enzyme. The aim of the current study was to determine the effect of intravenous NAC on plasma ADMA level when administered during hemodialysis in end-stage renal disease (ESRD) patients. MATERIALS AND METHODS: 40 patients with ESRD were randomized to receive a 4-hour intravenous infusion of NAC or placebo during a 4-hour hemodialysis session. There were 3 diabetic patients (15%) in the treatment group and 6 patients in the control group. Plasma ADMA levels were measured before and immediately after hemodialysis. Hemodynamic parameters, including pulse pressure, were also measured. The paired t-test was used to compare the difference of ADMA levels before and after hemodialysis in each group, while the independent t-test was used to compare the difference of ADMA levels between the groups. RESULTS: Compared with the pre-dialysis condition, there was a decrease of ADMA level in the control group (1.1253 +/- 0.1797 microM to 0.8676 +/- 0.1449 microM) (p < 0.001), and in the NAC group (1.1522 +/- 0.1737 microM to 0.7844 +/- 0.1586 microM) (p < 0.001). Compared with hemodialysis alone, NAC had a greater lowering effect on the ADMA level (21.3 vs. 31.9%, p < 0.05). CONCLUSION: N-acetylcysteine (NAC) administered intravenously during hemodialysis reduced asymmetric dimethylarginine (ADMA) levels more significantly than hemodialysis alone.     

Serum levels of the endothelial glycocalyx constituents and the early failure of forearm autologous arteriovenous fistulas in end-stage renal disease patients: a prospective cohort study

International Urology and Nephrology - The relationship between the endothelial glycocalyx constituents and the early failure of autologous arteriovenous fistulas (AVFs) in ESRD patients is still...     

Ineffectiveness of dipyridamole SPECT thallium imaging as a screening technique for coronary artery disease in patients with end-stage renal failure

The efficacy of dipyridamole single photon emission computed tomography (SPECT) thallium as a screening test for coronary artery disease (CAD), was studied in 45 patients with end-stage renal failure undergoing evaluation for renal transplantation. Coronary arteriography, dipyridamole SPECT thallium imaging and clinical follow-up were performed in all patients. Nineteen patients (42%) had an obstruction of 50% or more in at least one coronary artery. Fourteen patients had a positive thallium scan, but 7 of these were false-positives (sensitivity 37%, specificity 73%). The sensitivity was considerably lower than that quoted for non-ESRF patients in the literature, and significantly lower than a control group of 19 patients without ESRF having comparable severity and distribution of CAD. Five of the 6 patients who died of cardiac causes over a mean follow-up period of 25 months had normal thallium imaging, but all had significant coronary artery disease at cardiac catheterization. Dipyridamole SPECT thallium imaging has not proved a useful screening test for angiographically significant CAD, and does not predict cardiac prognosis in this population.