Influence of hemodialysis duration per week on parameters of dialysis adequacy and cardiovascular morbidity.

INTRODUCTION: The optimal length of dialysis is still under debate and current regimen of 12 hours a week is medically acceptable. The aim of this observational study was to confirm the relationship between different length of dialysis per week and the parameters of dialysis adequacy and cardiovascular morbidity. MATERIAL AND METHODS: The study included 206 patients (128 man and 78 females) who were on maintenance hemodialysis for more than 6 months. They were classified into three groups according to the length of dialysis per week: group I (12 hours), group II (15 hours) and group III (≥17.5 hours). RESULTS: Index of dyalysis adequacy values did not differ among the groups (group I, II, III = 1.32 vs. 1.51 vs. 1.42; p>0.05); however, the patients from group III had the best bicarbonate level (group I, II and III = 22.7; 21.4; 17.6 mmol/L; p<0.001). In comparison with group I (12 hours), longer dialysis duration was associated with significantly higher hemoglobin values (12.2 vs. 11.4 vs. 10.5 g/dL), less frequent use of erythropoietin stimulating agents (26.9% vs. 65% vs. 86.3%), lower stimulating agents weekly dose (median in group I, II, III = 2000 vs. 5000 vs. 4000 I.J.), lower stimulating agents resistance index (4.9 vs. 7.8 vs. 8.8), significantly higher level of serum albumin (42.3 vs. 40.7 vs. 38.2 g/dL), total cholesterol (5.1 vs. 4.7 vs. 4.5 mmol/L) and serum calcium level (2.38 vs. 2.42 vs. 2.28 mmol/L), less frequent use of phosphate binders (53.8% vs. 85% vs. 84.4%) and calcitriol (19.2% vs. 65% vs. 50.6%) and lower intact parathyroid hormone level (336 vs. 363 vs. 446 pg/ml). In addition, longer dialysis duration was associated with lower cardiovascular morbidity score (0.52 vs. 1.05 vs. 1.26). CONCLUSION: Duration of dialysis per week above the current standard positively correlates with parameters of hemodialysis adequacy.

Polymorphism of angiotensin converting enzyme in hemodialysis patients--association with cardiovascular morbidity.

INTRODUCTION: Cardiovascular morbidity and mortality are the major concern in dialysis patients and many risk factors are thought to be involved in its pathogenesis. Apart from traditional and non-traditional risk factors, the genetic susceptibility may be of importance, including renin-angiotensin system gene polymorphism. The aim of this study was to analyse renin-angiotensin system polymorphism in our group of hemodialysis patients and to correlate the findings with cardiovascular morbidity. MATERIAL AND METHODS: The study included 196 patients on regular hemodialysis on polysulphone membrane three times per week for more than six months. Genetic analysis was performed by using polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: Out of 196 patients, 55% had I/D genotype, 35% had D/D and 10% had I/I, including angiotensin-converting enzyme polymorphism. It was shown that the patients with D allele genotype developed a significantly higher incidence of left ventricular hypertrophy and peripheral vascular disease. The angiotensin-converting enzyme polymorphism showed a significant association with the incidence of cerebrovascular accident and hyperlipoproteinemia in our group of hemodialysis patients. CONCLUSION: The angiotensin-converting enzyme gene polymorphism is associated with the development of cerebrovascular accidents and hyperlipoproteinemia. Allele D of this gene increases the risk for the development of left ventricular hypertrophy and peripheral vascular disease significantly in hemodialysis patients. A longer follow-up is needed to make the definitive conclusion about the influence of angiotensin-converting enzyme polymorphism on cardiovascular morbidity and its importance in everyday clinical practice.

[Infections as the cause of death in hemodialysis patients--nine-year retrospective analysis].

INTRODUCTION: Patients on maintenance hemodialysis (HD) are at risk for infections. They represent one of the leading causes of death in this patient population which should be considered at high risk for lethal sepsis development. MATERIAL AND METHODS: Fatalities caused by infections in the period from 1997 to 2005 were analyzed retrospectively in order to investigate their frequency and relation to other causes of death. The role of vascular access (VA) and non-access related infections were also investigated Demographic characteristics, primary renal disease, length of time on HD, seasonal variation in deaths, the presence of diabetes, age over 65 and previous treatment with peritoneal dialysis (PD) were observed. RESULTS: Infections were the third leading cause of death (after cardiovascular and cerebrovascular causes) accounting for 10.1% of fatalities. Females were significantly more prevalent in this group in comparison to all other causes of death (63% vs. 41%, chi2=4.807; p<0.05). The difference was insignificant when all the other parameters were analyzed (age and age over 65, diabetes, HD duration, previous PD). Fatalities most frequently occurred in summer, as opposed to spring (insignificant difference). Infections related to VA were predominant, and the most important ones not related to VA were urinary tract infections and lower extremities gangrene. DISCUSSION AND CONCLUSIONS: Our results proved infections to be the important risk factor for mortality in HD patients. It is of great importance to recognize them in their early course and treat vigorously in order to reduce mortality in this population.

[Rare cardiomyopathy in haemodialysis patients: noncompaction of the ventricular myocardium].

INTRODUCTION: Isolated noncompaction of the ventricular myocardium is a rare, unclassified cardiomyopathy characterized by the presence of numerous prominent trabeculations and deep intratrabecular recesses which communicate with the left ventricular cavity. CASE REPORT: We describe a case of noncompaction of the ventricular myocardium in a 67 years old, asymptomatic patient on regular hemodialysis. The male patient, on haemodilaysis for three and a half yrs (mesangioproliferative glomerulonephritis was a cause of end-stage renal disease), with no previous signs or symptoms of congestive heart failure or ventricular tachycardia or systemic embolisation, had a routine echocardiography assessment. We found enlarged left (60 mm) and right ventricle (32 mm) with small ejection fraction (EF 48%), but the left ventricle wall was thickened (septum 13 mm and posterior wall 13 mm) with many small lacunes and chanells with blood flow in it. Spongious muscle made more than two thirds of the ventricle wall of both chambers. No thrombus was seen. Diastolic dysfunction was also present (EA). DISCUSSION: The most frequent symptoms in these patients are: heart failure, ventricular tachycardia, sudden cardiac death, cardioembolic events and syncopa. Because of that, all patients need oral anticoagulant therapy, and regular Holter ECG--to identify patients with ventricular tachycardia for whom implantabile cardioverter--defbrilator is indicated. CONCLUSION: Although non-compaction left ventricle is a very type of cardiomyopathy, it is important to be aware of its presence and criteria for diagnosis (left ventricle wall thickened with many trabeculations and deep intertrabecular recessess with blood flow in it), and the need for adequate therapy and follow-up.