Infective endocarditis in maintenance hemodialysis patients: fifteen years' experience in one medical center

BACKGROUND: Infective endocarditis (IE) is a serious infectious condition, with high morbidity and mortality in hemodialysis (HD) patients. This study was undertaken to determine the IE risk factors in maintenance HD patients, and the mortality risk factors. METHODS: We retrospectively reviewed all IE cases of maintenance HD patients at our center over the past 15 yrs (the study group). Regular HD patients without IE in the same period were used as the control group. The basic data of the two groups were analyzed to determine IE risk factors in HD patients. The in-hospital parameters of survival and mortality in the study group patients were used for mortality risk factors analysis. RESULTS: There were 18 definite, and two possible, IE diagnoses in the study group and no cases in the 268 controls. There was no significant difference in age, sex, diabetes, hypertension, underlying malignancy, previous cerebral vascular accident (CVA) history, and calcium multiplied by phosphate product. There was a significant difference between the two groups (study group vs. controls) in pacemaker implant history (15 vs. 1.1%, p<0.01), previous heart surgery history (15 vs. 0.4%, p<0.01), congestive heart failure (CHF) (50 vs. 10.4%, p<0.05), duration on maintenance HD (12.9+/-19.1 vs. 57.9+/-42.3 months, p<0.001), serum albumin at the time of admission (2.91+/-0.40 vs. 3.96+/-0.52 g/dL, p<0.001). There were more patients dialyzed via non-cuffed dual-lumen catheters in the study group (55 vs. 0%, p<0.001), and fewer patients dialyzed via arteriovenous fistula (AVF) (25 vs. 87.7%, p<0.001). The mortality in HD patients with IE was high (60%), especially in patients with methicillin-resistant Staphylococcus aureus (MRSA) endocarditis (100%). The most common pathogen was S. aureus (n=12). MRSA was more common than methicillin-susceptible S. aureus (MSSA) (67 vs. 33%). Univariant analysis of in-hospital clinical parameters for mortality revealed no significant difference in age, diabetes, dual-lumen catheter implantation, serum albumin, time to diagnosis, and time to antibiotic use. Borderline statistical significance was noted in serum C-reactive protein (CRP) (p=0.051), and blood glucose level (p=0.056). There were more IE cases due to MRSA in the mortality group than in the survival group (8 vs. 0 cases, p=0.013), but fewer cases due to MSSA (0 vs. 4 cases, p=0.050). CONCLUSIONS: IE should be considered in HD patients with the following risk factors, which include previous heart surgery or pacemaker implantation, shorter HD duration, and especially for patients dialyzed via dual-lumen catheters. The in-hospital clinical parameters including CRP and blood sugar level can offer information concerning prognosis. Since MRSA has increased in recent years and is associated with high mortality, strategies for prevention and treatment require development.     

Mortality risk factors in chronic haemodialysis patients with infective endocarditis.

BACKGROUND: It is well documented that infective endocarditis (IE) is strongly associated with morbidity and mortality in haemodialysis (HD) patients. Less clear are the mortality risk factors for IE, particularly in an urban African-American dialysis population. METHODS: IE patients were identified from the medical records for the period from January 1999 to February 2004 and confirmed by Duke criteria. The patients were classified as 'survivors' and 'non-survivors' depending on in-hospital mortality, and risk factors for IE mortality were determined by comparing the two cohorts. Survivors were followed as out-patients with death as the endpoint. RESULTS: A total of 52 patients with 54 episodes of IE were identified. A catheter was the HD access in 40 patients (74%). Mitral valve (50%) was the commonest valve involved, and Gram-positive infections accounted for 87% of IE. In-hospital mortality was high (37%) and valve replacement was required for 13 IE episodes (24%). On logistic regression analyses, mitral valve disease [P = 0.002; odds ratio (OR) = 15.04; 95% confidence interval (CI) = 2.70-83.61] and septic embolism (P = 0.0099; OR = 9.56; 95% CI = 1.72-53.21) were significantly associated with in-hospital mortality. Using the Cox proportional hazards model, mitral valve involvement (P = 0.0008; hazard ratio 4.05; 95% CI = 1.78-9.21) and IE related to drug-resistant organisms such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus sp. (P = 0.016; hazard ratio 2.43; 95% CI = 1.18-5.00) were associated with poor outcome after hospital discharge. CONCLUSIONS: IE was associated with high mortality in our predominantly African-American dialysis population, when the mitral valve was involved, or septic emboli occurred and if MRSA or VRE were the causal organisms.     

Arteriovenous fistula use and heart disease in long-term elderly hemodialysis patients: analysis of United States Renal Data System Dialysis Morbidity and Mortality Wave II

BACKGROUND: There are some concerns that arteriovenous fistula (AVF) use or other dialysis specific factors may exacerbate cardiovascular disease in long-term hemodialysis (HD) patients. METHODS: We performed a historical cohort study of the United States Renal Data System Dialysis Morbidity and Mortality Wave II study, limited to 993 patients who started HD in 1996 with valid information on vascular access and who were primarily eligible for Medicare at the start of the study. We assessed the association between hemodialysis vascular access and heart disease, defined as Medicare Claims for heart failure (HF, International Classification of Diseases (ICD9) code 428.x) and acute coronary syndromes (ACS, ICD9 code 410.x and 411.x). Cox proportional hazards regression (using propensity analysis) was used to model adjusted hazard ratios (AHR) for the association between patients factors and heart disease after dialysis. RESULTS: The rate of HF per 100 person years at risk (PYAR) was 19.6 among AVF users, 25.7 among patients using polytetrafluoroethylene grafts (grafts), and 31.1 among patients using temporary catheters. Corresponding rates of ACS were 8.2 among AVF users, 11.0 among users of grafts, and 12.4 among users of temporary catheters. In Cox Regression analysis, there was no significant association between AVF use and either HF or ACS. This lack of association was consistent across gender, diabetes, race, and age. CONCLUSIONS: We found that AVF use had no significant association with the incidence of HF or ACS. We conclude that use of AVF by 60 days after the start of dialysis is not associated with an increased risk of later non-fatal cardiovascular outcomes in long-term hemodialysis patients.     

Infective endocarditis in hemodialysis patients: clinical features, echocardiographic data and outcome

Background  Infective endocarditis (IE) is a dreaded complication in hemodialysis (HD) patients and is strongly associated with morbidity and mortality. Objectives  Our aim was to investigate clinical and echocardiographic characteristics, microbiological profile, management and outcome of patients on HD in a Tunisian (Tunisia, North Africa) high-volume tertiary-care centre. Methods  Among 182 patients who fulfilled the modified Duke criteria for infective endocarditis between January 1997 and December 2006, 16 were on chronic HD and were included in the study. Results  Mean age was 52.5 ± 22.3 years, ten were male and arteriovenous fistulas were the most commonly used access sites (12 out of 16 cases). Average duration of dialysis was 27.3 ± 30 months. Major causative organisms were Staphylococcus species (including methicillin-resistant Staphylococcus aureus) in 11 (68.7%) of the 16 cases. The mitral valve was the most commonly affected [9 patients out of 16 (56.2%)], followed by aortic valve in 4 cases (25.0%) and tricuspid valve in 1 case (6.2%). Complications were frequent, including congestive heart failure (56.2%), secondary septic localisations (31.2%), arterial emboli (18.7%), and cerebral haemorrhage (6.2%). Five patients underwent surgery and seven died during hospitalization (43.7% mortality rate). No recurrences of IE were recorded in the nine survivors after average 21.7 ± 17.3 months follow-up. Conclusion  In this largest reported confirmed IE series in dialysis patients in a developing country, mortality was very high; mitral valve was the most commonly affected valve. Staphylococcus species were the major causative organisms.     

The application status of vascular access at initiation of hemodialysis in patients with end stage renal disease—a single center study

Objective To investigate the types and outcome of vascular access in patients with end stage renal disease (ESRD) initiated hemodialysis (HD), and provide the basis for advancing the proportion of planned HD with arteriovenous fistula (AVF). Methods Clinical data, vascular access types at the initiation of HD, the outcomes of all types of dialysis access and the conversion of renal replacement therapy of ESRD patients who initiated HD in the first affiliated hospital of zhejiang university between January 2009 and December 2011 were retrospectively studied. Results A total of 836 patients were included in our study. Among them 510 were males and 326 were females. The average age was (49.77±17.65) years old. The major primary diseases were primary glomerular disease (72.73%), diabetic nephropathy (11.60%)and hypertensive nephrosclerosis (3.95%). Only 73 patients (8.73%) used AVF as the vascular access at the initiation of HD, another 763 patients (91.27%) used central venous catheter. Six months after the start of dialysis, 542 patients (81.5%) had used AVF as permanent vascular access, 123 patients (18.5%)had used the tunneled cuffed catheter, 54 patients had received a transplant and 55 patients had converted to peritoneal dialysis. The results of logistic regression analysis suggested that being male, patients from outside hangzhou and patients whose glomerular filtration rate were lower than 5 ml•min-1•(1.73 m2)-1 were the risk factors of using central venous catheters at the initiation of HD. Conclusions Only a minority of patients used AVF at the initiation of HD, but most of the other patients switched to AVF within the following six months. Increasing the proportion of AVF as the vascular access of planned HD is still our current goal.     

Vascular access for hemodialysis: the impact on morbidity and mortality

BACKGROUND: In chronic hemodialysis (HD), central venous catheter (CVC) use seems associated with an increased risk of death. This study, using registry data, evaluated the morbidity and mortality risk associated with the use of different permanent vascular access (VA) in a HD patient cohort. METHOD: We evaluated hospitalization and death rate in prevalent and incident HD patients recorded in the uremic registry of Campania (southern Italy) for 2001. Patients were divided into three groups: CVC, artero-venous graft (AVG) and artero-venous fistula (AVF). RESULTS: One hundred and eleven dialysis units in the Campania region (69%) provided data. A total of 2201 out of 3387 prevalent HD patients were included: 92 patients (4.2%) were on CVC, 24 patients (1.1%) were on AVG and 2085 patients (94.7%) were on AVF. In comparison with AVF, the CVC group had a greater prevalence of female gender, old age, diabetes, comorbidities, hypoalbuminemia, anemia, erythropoietin (EPO) resistance, and less frequent synthetic membrane use, but had a similar dialysis duration (hr/week). Similar data were collected in the 635 incident patients registered in 2001. During the study, in both prevalent and incident CVC patients, either hospitalization or death rates were enhanced; however, the difference in the relative risk (RR) of death disappeared after correction for age, gender, malnutrition, diabetes, hemoglobin, albumin and comorbidity. Among incident patients, survival analysis was performed in patients remaining on the same VA type throughout the follow-up period; while a similar survival between groups was demonstrated in the 1st year of follow-up, survival was worse in the CVC group during the 2nd year of follow-up; however, this difference also disappeared in the adjusted analysis. CONCLUSION: This cohort study demonstrates that in chronic dialysis patients CVC choice, with respect to AVF, is mainly associated with female gender, advanced age and worse clinical conditions at baseline, and a worst outcome in both prevalent and incident CVC patients compared to AVF patients. Hospitalization, mortality rate and RR of death increased significantly; however, differences disappeared after correction for comorbidity. Therefore, these data suggest that CVC use per se is not associated with increased mortality risks with respect to AVF.     

The role the type of vascular access plays in the transmission of hepatitis C virus in a high prevalence hemodialysis unit

Background: The necessity of having a vascular access site as well as extracorporeal blood circulation, may add to the risk for patients being dialyzed in units with high HCV prevalence of acquiring hepatitis C virus (HCV) infection. This study endeavors to determine the role the type of vascular access plays in the transmission of HCV infection in the hemodialysis (HD) unit of a Middle Eastern country. Methods: The records of 198 patients with end-stage renal disease (ESRD) enrolled on maintenance HD from November 1995 to November 2000 at this tertiary care center, were retrospectively reviewed to match the HCV prevalence and seroconversion rates among patients groups being dialyzed through various types of vascular accesses. Factors such as, number of units of blood transfused and dialytic age (time-span since the initiation of the HD treatment), implicated in transmission of HCV infection in HD units, were also recorded, and compared among these cohorts. Results: The overall, high HCV seroprevalence of 43.4% (86/198) and annual seroconversion rate of 8.6% per year were recorded. Patients with arteriovenous fistula (AVF) documented peak anti-HCV prevalence [61.7% (63/102)] and annual seroconversion rates (12.3%) as compared to lowest prevalence of 12.9% (4/34) and seroconversion rate of 2.5%, observed among patients with permanent Catheters (PC). Patients dialyzed through polytetrafluoroethylene (PTFE) grafts recorded the next highest HCV prevalence of 47.8% (11/23) with seroconversion rate of 9.5% but temporary catheter (TC) group had HCV prevalence of 19% (8/42) and seroconversion rate of 3.8% [Odd Ratio (OR)-1.58, 95% Confidence Interval (CI) (0.37-7.12), p-NS]. Conclusions: Considerably higher annual seroconversion rates in AVF [OR-10.90, 95% CI (3.2-40.0), p<0.0001] and PTFE [OR-5.71, 95% CI (1.31-26.79), p<0.016)] groups, appear to suggest that the patients being dialyzed through AVF and PTFE, carried significantly higher risk of acquisition of HCV infection compared to those dialyzed through TC and PC (reference group). This could possibly be attributed to likely accessibility of HCV to blood circulation due to possible breakdown of standard infection control precautions during repeated punctures and cannulations of AVF and PTFE to perform a HD, in a unit with high baseline HCV prevalence.     

Early failure rates of arterovenous fistulas for hemodialysis: evaluation of six-year activity

Maintenance and complications of vascular access (VA) for hemodialysis (HD) represent the leading cause of morbidity and health care cost among end stage renal disease population. To define the reasons for the use of a particular VA at the beginning of replacement treatment, we prospectively evaluated the early failure rate and survival of arterovenous fistula (AVF) in 183 patients. These patients had high prevalence of cardiovascular risk factors and co-morbid conditions, and began HD in our renal unit from the 1st of January 1995. As a part of this study the present analysis focuses on potential predictors of early failure of the first AVF (within the first 7 days after the operation). Overall, 279 AVF were prepared: 193 at the wrist and 86 at the upper arm, including 11 prosthetic grafts; 150 patients (82%) were given a distal AVF in the first operation. Our conservative policy resulted in a relatively high prevalence of native AVF in use among our prevalent HD patients (84.3%). Early failure of the first VA was 10.4%. Multivariate analysis showed that this event was neither significantly associated with all traditional risk factors and co-morbids tested, nor with the operating surgeon. We conclude that in this prospectively studied cohort, the high rate of native AVF created in order to preserve the vascular bed, though associated with a high early failure rate unaffected by traditional cardiovascular risk factors, resulted in a low proportion of permanent catheters and arterovenous grafts in use among prevalent HD patients. (The Journal of Vascular Access 2001; 2: 154-160).     

Back to the Future: How Biology and Technology Could Change the Role of PTFE Grafts in Vascular Access Management

Although the arteriovenous fistula (AVF) is the preferred mode of dialysis vascular access, AVF maturation failure remains a huge clinical problem, often resulting in a prolonged duration of use of tunneled dialysis catheters. In contrast, polytetrafluoroethylene (PTFE) grafts do not suffer from early failure, but have significant problems with later stenosis and thrombosis. This review will initially summarize the pathology and pathogenesis of PTFE graft dysfunction and will then use this as a basis for describing some novel therapies, which may have the potential to reduce PTFE graft dysfunction. Finally, we will emphasize that the introduction of such therapies could be an important first step toward individualizing overall vascular access care.     

Haemodialysis dose is independent of type of surgically-created vascular access

Background: In the United States, the use of polytetraflourotheylene (PTFE) graft compared with native arteriovenous fistula (AVF) for haemodialysis vascular access has been increasing despite a greater than two-fold higher incidence of thrombosis and infection associated with PTFE grafts. Methods: We studied 214 haemodialysis patients with not more than two revisions of their vascular access, to determine whether any relationship exists between the type of haemodialysis vascular access and dialysis dose assessed primarily by urea reduction ratio (per cent reduction in blood urea nitrogen concentration after a dialysis session). Serum albumin concentration was used as a secondary outcome measure of dialysis adequacy. Urea reduction ratio and predialysis serum albumin concentration were measured at onset of study and at 4-week intervals and mean values were calculated for each subject. Results: The 214 patients (118 males, 96 females) included 173 Blacks (81%), 26 Whites (15%), and 15 Hispanics (7%), of mean (±SD) age 55.6±15.5 years. Of these 214 subjects, 111 (52%) had a native AVF, while 103 (48%) had a PTFE graft. Both mean urea reduction ratio (native AVF=69±6.7% vs PTFE graft=70±7.3%; P=0.31), and mean serum albumin concentration (native AVF=4.02±0.39 g/dl vs PTFE graft=4±0.33 g/dl; P=0.59) were equivalent in both groups. Separate multiple logistic regression analyses with type of vascular access as one of the independent variables, found no significant relationship between type of vascular access and either a urea reduction ratio >65% (P=0.67), or a serum albumin concentration >4 g/dl (P=0.89), after adjustment for age of vascular access, access revision, location of access, dialyser urea clearance, length of dialysis treatment, body weight, and age. Conclusion: We conclude that PTFE grafts do not permit delivery of better dialysis than native AVF. The increasing use of PTFE grafts in the United States does not have any clinical justification.     

Tunnelled internal jugular vein catheters with taurolidine lock: an acceptable challenge to arterio-venous fistula in 70 years old haemodialyzed patients: a prospective pilot study

Arteriovenous fistula (AVF) is still in 2010 the gold standard of vascular(2) access in haemodialysis (HD) patients. Nevertheless it may be difficult to obtain and/or to use AVF in elderly. With this prospective randomised pilot study, we compare two strategies of vascular access in 70 years old or more new HD patients. AVF were compared to tunnelled jugular vein catheters (TIJC) with taurolidine as bacterial lock solution. Results were as follow: [table: see text] The responses with the visual analogic scale of comfort was 8/10 for TIJC and 5/10 with AVF * P<0.05. In five TIJC patients, heparin was added with success to taurolidine because of partial clotting of catheters. Albuminemia was significantly lower in AVF failure patients compared to AVF success patients (24.8g/L vs 31.1g/L). This pilot study allows to conclude that TIJC is an acceptable challenge to AVF in haemodialysed patients of 70 years or more in a two years long use.     

Surgery for infective endocarditis: determinate factors in the outcome

AIM: The appropriate operative procedures for treatment of infective endocarditis (IE) are still controversial. The authors reviewed their own operative results focusing on preoperative risk factors, intraoperative findings and operative procedures. METHODS: The authors reviewed the cases of 40 adult patients who had undergone surgery since 1999. The mean age of patients was 58 years ranging from 31 to 78 including 30 males and 10 females. Thirty-three patients had native valve endocarditis (NVE) and the remaining seven patients had prosthetic valve endocarditis (PVE). Diseased lesions were located in the mitral valve (MV) in 21 patients, aortic valve in 15 and mitral plus aortic valves in four. Twenty-eight patients (70%) were operated on during the active phase of IE. Streptococcus, Staphyrococcus and Enterococcus species were predominant in the bacterial examination. RESULTS: Active vegetation was observed in 26 (65%) patients. Perforation of valve leaflets was observed in 11 (28%) cases. Changes of native MV leaflet were mild in 8 (40%) out of 20, which seemed to be reparable, while, changes of the native aortic valve leaflet were moderate to severe in 13 (87%) out of 15 patients. Valvular annuls were involved in the infection in 17 (43%) patients. Of the 33 NVE patients, prosthetic valve replacement was performed in 29 patients incduding 19 mitral and 15 aortic valves. MV plasty was performed in 4 patients. In seven PVE patients, prosthetic MV replacement was performed twice. In the aortic group, three patients underwent aortic root translocation, The Ross procedure and standard root replacement were performed respectively. Four patients died after surgery including one NVE case and three PVE cases. Three PVE patients who underwent aortic root translocation or the Ross procedure survived. The hospital mortality of NVE and PVE surgery was 3% and 43% (P<0.01), respectively. By univariant anlysis, there were no significant correlations between operative results and preoperative factors such as bacteria, infective phase, cardiac failure, renal failure, sepsis or brain morbidity. The only significant factor on hospital mortality was PVE. Three patients died of non-cardiac diseases during the follow-up period. CONCLUSION: Operative results of NVE were good after complete resection of infective sites including valve annulus. Both valve replacement and plasty were available for NVE patients. In PVE, new strategies are indispensable and aortic root translocation or the Ross procedure should be a treatment of choice.     

Vascular access use in Europe and the United States: results from the DOPPS.

BACKGROUND: A direct broad-based comparison of vascular access use and survival in Europe (EUR) and the United States (US) has not been performed previously. Case series reports suggest that vascular access practices differ substantially in the US and EUR. We report on a representative study (DOPPS) which has used the same data collection protocol for> 6400 hemodialysis (HD) patients to compare vascular access use at 145 US dialysis units and 101 units in five EUR countries (France, Germany, Italy, Spain, and the United Kingdom). METHODS: Logistic analysis evaluated factors associated with native arteriovenous fistula (AVF) versus graft use or permanent access versus catheter use for prevalent and incident HD patients. Times to failure for AVF and graft were analyzed using Cox proportional hazards regression. RESULTS: AVF was used by 80% of EUR and 24% of US prevalent patients, and was significantly associated with younger age, male gender, lower body mass index, non-diabetic status, lack of peripheral vascular disease, and no angina. After adjusting for these factors, AVF versus graft use was still much higher in EUR than US (AOR=21, P < 0.0001). AVF use within facilities varied from 0 to 87% (median 21%) in the US, and 39 to 100% (median 83%) in EUR. For patients who were new to HD, access use was: 66% AVF in EUR versus 15% in US (AOR=39, P < 0.0001), 31% catheters in EUR vs. 60% in US, and 2% grafts in EUR vs. 24% in US. In addition, 25% of EUR and 46% of US incident patients did not have a permanent access placed prior to starting HD. In EUR, 84% of new HD patients had seen a nephrologist for> 30 days prior to ESRD compared with 74% in the US (P < 0.0001); pre-ESRD care was associated with increased odds of AVF versus graft use (AOR=1.9, P=0.01). New HD patients had a 1.8-fold greater odds (P=0.002) of starting HD with a permanent access if a facility's typical time from referral to access placement was < or =2 weeks. AVF use when compared to grafts was substantially lower (AOR=0.61, P=0.04) when surgery trainees assisted or performed access placements. When used as a patient's first access, AVF survival was superior to grafts regarding time to first failure (RR=0.53, P=0.0002), and AVF survival was longer in EUR compared with the US (RR=0.49, P=0.0005). AVF and grafts each displayed better survival if used when initiating HD compared with being used after patients began dialysis with a catheter. CONCLUSION: Large differences in vascular access use exist between EUR and the US, even after adjustment for patient characteristics. The results strongly suggest that a facility's preferences and approaches to vascular access practice are major determinants of vascular access use.     

Longitudinal comparison of dialysis access methods: Risk factors for failure

Purpose: To compare dialysis access patency rates and identify risk factors for failure. Methods: All access procedures at our institution from 1987 to 1996 were reviewed. Primary procedures were surgically implanted dual-lumen central venous hemodialysis catheters (SIHCs), peritoneal dialysis catheters (PDCs), arteriovenous fistulas (AVFs), and prosthetic shunts (PTFEs). Results: Five hundred eighty-five primary procedures (236 PTFEs, 87 AVFs, 112 SIHCs, and 150 PDCs) and 259 secondary procedures (215 PTFEs, 14 AVFs, 0 SIHCs, and 30 PDCs) were performed on 350 patients. By life table analysis, SIHCs exhibited the lowest primary patency rate (9% at 1 year; p < 0.0001), whereas PDCs had the highest primary patency rate (57% at 1 year; p < 0.02). The primary patency rates of AVFs and PTFEs was similar, with 43% and 41% 1-year patency rates, respectively (p = 0.70). Less-stringent reporting methods would have increased apparent 1-year patency rates by 9% to 41%. With regard to secondary patency, there was no significant difference between PTFEs and PDCs, with 1-year patency rates of 59% and 70%, respectively (p = 0.62), but PTFEs were more frequently revised. In addition, there was no significant difference between AVF and PTFE secondary patency rates, with 1-year patency rates of 46% and 59%, respectively. Early differences in patency rates for AVFs, PTFEs, and PDCs diminished over time, and at 4 years AVFs had the best secondary patency rate (p = 0.6). The most common reasons for access failure were: PTFEs, thrombosis; AVFs, thrombosis and failure to mature; SIHCs, inadequate dialysis; PDCs, infection and inadequate exchange. By regression analysis, a history of a previous unsalvageable PTFE was the only significant risk factor for failure of a subsequent PTFE (p < 0.01), and the risk of graft failure increased exponentially with the number of previous PTFE shunts. Diabetes was the only significant risk factor for failure of PDCs (p < 0.02; odds ratio, 2.0). Conclusions: The patency rate for PTFEs is similar to that for AVFs, but AVFs require fewer revisions. When replacing a failed access graft, the risk of PTFE failure increases with the number of prior unsalvageable PTFE shunts. PDCs have excellent patency rates, but failure rates are doubled in patients with diabetes. Because of poor patency rates and inadequate dialysis flow rates, SIHCs should be avoided when possible. Reporting methods dramatically affect apparent patency rates, and reporting standards are needed to allow meaningful comparisons in the dialysis access literature. (J Vasc Surg 1997;26:1009-19.)     

Infective endocarditis in chronic haemodialysis: two treatment strategies.

BACKGROUND: Infective endocarditis (IE) is more frequent in patients on chronic haemodialysis (CHD) than in the general population and vascular access is the more frequent identified port of its entry. According to experimental and clinical studies the vascular access may also interfere with the treatment of IE. To improve the treatment of IE in CHD, patients were temporarily switched to peritoneal dialysis (PD) after the removal of the vascular access. In this preliminary report the outcome of IE in those CHD patients switched to PD is compared with the outcome in IE patients who remained on CHD. METHODS: All cases of IE that occurred during a 5 year period were retrospectively analysed. The Duke criteria for IE were used for diagnosis. All patients underwent transoesophageal echocardiography. All patients were treated with the same schedule of antibiotic treatment. The vascular access of a patient was removed when it was judged to be the source of infection. RESULTS: Twenty-one patients were studied. Twelve patients had been temporarily switched to PD after the diagnosis of IE and nine patients had remained on CHD treatment. There were not statistically significant differences between the two groups with respect to demographic data, comorbid diseases and the frequency of Staphylococcus aureus as the causative germ. In-hospital mortality was 8.3% in patients switched to PD and 55.5% in patients maintained on HD (P: 0.03). CONCLUSIONS: The data presented here suggest that the high mortality of IE in CHD patients may also be associated with the vascular access necessary for HD. If these results are confirmed by prospective studies with higher numbers of patients, PD could turn out to have a place in the treatment of IE in CHD patients.     

Effects of smoking and blood eosinophil count on the development of arteriovenous fistulae thrombosis in hemodialysis patients

Arteriovenous fistulae (AVF) failure is the most common cause of morbidity and hospitalization in hemodialysis (HD) patients. The purpose of this study was to determine the effects of smoking and blood eosinophil count on the development of AVF thrombosis in HD patients. This cross-sectional study included 141 patients (M/F 80/61; age 43.4 +/- 11.6 years, HD duration 7.7 +/- 4.4 years). The following were analyzed as possible risk factors for AVF failure for all patients: demographic features, dialysis time, smoking, medications, body mass index, comorbid diseases, and various laboratory parameters (whole blood count and serum levels of albumin, calcium, phosphorus, uric acid, C-reactive protein, ferritin, and parathyroid hormone). AVF thrombosis was detected in 60 patients; in contrast, 81 patients had no thrombosis. Distributions of age, gender, and HD duration were similar between both groups. Univariate analysis showed that snuffbox AVF location (P < .0001), higher blood eosinophil count (P < .0001), smoking (P < .01), and higher hematocrit level (P < .05) were all associated with AVF thrombosis. According to multivariate analysis by logistic regression models, eosinophil count (RR = 1.005, P < .05) and snuffbox location (RR = 5.970, P < .05) were predictors of AVF thrombosis. When AVF location was excluded from the analysis, smoking (RR = 4.140, P < .01) and high blood eosinophil count (RR = 1.006, P < .005) were independent risk factors for thrombosis. Our study indicates that smoking and high blood eosinophil count may contribute to the development of AVF thrombosis.     

Surgical management for active infective endocarditis: A single hospital 10 years experience

Objective  Surgical treatment of active infective endocarditis (IE) requires not only homodynamic repair, but also, special emphasis on the eradiation of the infection to prevent recurrence. This study was undertaken to examine the outcome of surgery for active infective endocarditis. Methods  One hundred sixty-four consecutive patients (pts) underwent valve surgery for active IE in Madani Heart Centre (Tabriz, Iran) from 1996 to 2006. Patients presenting with IE diagnosis (according to Duke Criteriaset) were eligible for study. Results  The mean age of patients was 36.3±16 years overall: 34.6±17.5 years for native valve endocarditis and 38.6±15.2 years for prosthetic valve endocarditis (p=0.169). Ninety one (55.5%) of patients were men. The infected valve was native in 112 (68.3%) of patients and prosthetic in 52 (31.7%). In 61 (37%) patients, no predisposing heart disease was found. The aortic valve was infected in 78 (47.6%), the mitral valve in 69 (42.1%), and multiple valves in 17 (10.3%) of patients. Active culture-positive endocarditis was present in 81 (49.4%) whereas 83 (50.6%) patients had culture-negative endocarditis. Staphylococcus aureus was the most common isolated microorganism. Ninety patients (54.8%) were in NYHA classe III and IV. Mechanical valves were implanted in 69 patients (42.1%) and bioprostheses in 95 (57.9%), including homograft in 19 (11.5%). There were 16 (9%) operative deaths, but there was only 1 death in patients that underwent aortic homograft replacement. Reoperation was required in 18 (10.9%) of cases. On multivariate logistic regression analysis, Staphylococcus aureus infection (p=0.008), prosthetic valve endocarditis (p=0.01), paravalvular abscess (p=0.001) and left ventricular ejection fraction less than 40% (p=0.04) were independent predictors of inhospital mortality. Conclusions  Surgery for infective endocarditis continues to be challenging and associated with high operative mortality and morbidity. Prosthetic valve endocarditis, impaired ventricular function, paravalvular abscess and Staphylococcus aureus infection adversely affect in-hospital mortality. Also we found that aortic valve replacement with an aortic homograft can be performed with acceptable in hospital mortality and provides satisfactory results.     

Rarity of invasiveness in right-sided infective endocarditis

Objective

The rarity of invasiveness of right-sided infective endocarditis (IE) compared with left-sided has not been well recognized and evaluated. Thus, we compared invasiveness of right- versus left-sided IE in surgically treated patients.

Evaluation of the practice of routine culturing of native valves during valve replacement surgery

BACKGROUND: We routinely cultured native heart valves removed during valve replacement surgery even when infected carditis (IE) was not suspected. Several probable contaminated cultures prompted us to evaluate this practice. METHODS: The medical records of all patients who had positive valve cultures from 1995 to 1997 were reviewed for admission diagnoses, operative surgery, pathology and microbiology report, postoperative infections, and antibiotic use. Cases were excluded only for incomplete medical records or preoperative suspicion of IE. Long-term outcome for the cases was obtained from review of outpatient records and phone contact with the patient or physician. RESULTS: Thirty-two of 222 (14.4%) evaluable patients had positive valve cultures. Coagulase-negative Staphylococcus was the most common isolate. IE was not suggested in any of these cases based upon the surgical or the pathology report. Only 1 of 32 (3%) developed postoperative prosthetic valve endocarditis (PVE). Three patients died of unrelated causes, and the 28 surviving patients showed no sign of PVE, with a mean follow-up of 23 months. CONCLUSIONS: The incidence of false-positive native valve cultures is high. Positive cultures did not predict the occurrence of PVE sufficiently to justify obtaining them. Treating patients who had positive native valve cultures would have been unwarranted and poses an unnecessary risk.     

Surgery for infective endocarditis—analysis of factors affecting outcome

PurposeDespite advances in medical care, infective endocarditis (IE) has high mortality. Surgery for IE though recommended for complications of the disease is still not commonly offered due to conflicting reports in the literature. We reviewed our results of surgery for IE from the last 5 years to assess their outcome.MethodsA retrospective review from a single center of consecutive patients who underwent surgery for infective endocarditis from September 2014 to December 2019 was done. Data was collected from hospital records and follow-up done up to May 2020. Outcomes evaluated were mortality, follow-up survival, and postoperative complications. Factors affecting mortality and survival were analyzed.ResultsNinety-seven patients underwent surgery for IE during this period. Seventy-nine had native valve endocarditis (NVE) and 18 had prosthetic valve endocarditis (PVE). The overall postoperative mortality was 13%, with mortality for native valve endocarditis being 11% and that for prosthetic valve endocarditis being 22%, which was not statistically significant. Three-year survival for the overall group was 88.7% with 88.1% for NVE and 91.7% for PVE. Multivariate predictors of operative mortality were a high EuroSCORE II, diabetes mellitus, and the presence of Staphylococcus organism.ConclusionSurgery for infective endocarditis has a very acceptable early outcome and intermediate-term survival.