Effects of thrice weekly nocturnal hemodialysis on arterial stiffness.

OBJECTIVE: In this study, we compared the changes in arterial stiffness in chronic hemodialysis patients treated with 8-h vs. 4-h thrice weekly in-center hemodialysis. METHODS: Sixty prevalent chronic hemodialysis patients assigned to 8-h nocturnal in-center thrice weekly HD (NHD) and 60 control cases assigned to 4-h thrice weekly conventional HD (CHD) were followed for one year. Radial-carotid pulse wave velocity, augmentation index and echocardiography were performed at baseline and 12th month. RESULTS: Mean age of the patients was 49±11 years, 30.8% were female, 27.5% had diabetes mellitus and mean dialysis vintage was 57±47 months. Baseline demographical, clinical and laboratory parameters were similar between groups. During a mean follow-up of 15.0±0.1 months, blood pressure remained similar in both groups while the number of mean daily anti-hypertensive substances decreased in the NHD group. In the NHD group, time-averaged serum phosphorus and calcium-phosphorus product were lower than the CHD group. Pulse wave velocity and augmentation index decreased in the NHD group (from 11.02±2.51 m/s to 9.61±2.39 m/s and from 28.8±10.3% to 26.2±12.1%; p=0.008 and p=0.04, respectively). While augmentation index increased in the CHD group (28.0±9.4 to 31.0±10.7%, p=0.02), pulse wave velocity did not change. Subendocardial viability ratio and ejection duration improved in the NHD group (from 135±28 to 143±25%, p=0.01 and from 294±34 ms to 281±34 ms, p=0.003, respectively), accompanied by regression of left ventricular mass index. In multiple stepwise linear regression analyses, NHD was associated with improvements in augmentation index, ejection duration and subendocardial viability ratio. CONCLUSIONS: These data indicate that arterial stiffness is ameliorated by implementation of longer hemodialysis sessions.

Factors related to pulse wave velocity and augmentation index in chronic hemodialysis patients.

BACKGROUND: Augmentation index (AIx) and pulse wave velocity (PWV) are early markers of atherosclerotic vascular changes and also have been shown to be predictive of cardiovascular disease and total mortality. The aim of our study was to evaluate the relationship between PWV and AIx-HR75, which is the corrected form of AIx according to a heart rate of 75 beats/min, echocardiographic parameters and biochemical parameters in chronic hemodialysis (HD) patients. SUBJECTS AND METHODS: AIx-HR75 and PWV were measured in 556 HD patients by applanation tonometry using the SphygmoCor device. RESULTS: The mean PWV and AIx-HR75 values of the study group were 10.2 ± 2.4 and 28.4 ± 10.2 m/s. A positive correlation was found between PWV and AIx-HR75 (r = 0.214, p = 0.000). AIx-HR75 correlated with age (r = 0.093, p = 0.028), body surface area (BSA) (r = -0.194, p = 0.000), mean arterial pressure (MAP) (r = 0.335, p = 0.000), pulse pressure (PP) (r = 0.212, p = 0.000), cardiothoracic index (r = 0.155, p = 0.016), and presence of left ventricular hypertrophy (r = 0.152, p = 0.001). PWV correlated with MAP (r = 0.208, p = 0.000), PP (r = 0.098, r = 0.021), left ventricular mass (r = 0.105, p = 0.023), and predialysis sodium level (r = -0.105, p = 0.023). In the multivariate analyses, PWV was associated with MAP (t = 3.78, p = 0.000), presence of diabetes (t = 3.20, p = 0.001), and predialysis sodium level (t = -2.06, p = 0.040), and AIx-HR75 was associated with age (t = 2.48, p = 0.014), female sex (t = 3.98, p = 0.000), BSA (t = -2.15, p = 0.033), and MAP (t = 7.02, p = 0.000). CONCLUSION: There is a strong association between MAP and arterial stiffness parameters in HD patients. We feel that efficient control of blood pressure could lead to reduced arterial stiffness in HD patients.

Comparison of 4- and 8-h dialysis sessions in thrice-weekly in-centre haemodialysis: a prospective, case-controlled study.

BACKGROUND: Longer dialysis sessions may improve outcome in haemodialysis (HD) patients. We compared the clinical and laboratory outcomes of 8- and 4-h thrice-weekly HD. METHODS: Two-hundred and forty-seven HD patients who agreed to participate in a thrice-weekly 8-h in-centre nocturnal HD (NHD) treatment and 247 age-, sex-, diabetes status- and HD duration-matched control cases to 4-h conventional HD (CHD) were enrolled in this prospective controlled study. Echocardiography and psychometric measurements were performed at baseline and at the 12th month. The primary outcome was 1-year overall mortality. RESULTS: Overall mortality rates were 1.77 (NHD) and 6.23 (CHD) per 100 patient-years (P = 0.01) during a mean 11.3 ± 4.7 months of follow-up. NHD treatment was associated with a 72% risk reduction for overall mortality compared to the CHD treatment (hazard ratio = 0.28, 95% confidence interval 0.09-0.85, P = 0.02). Hospitalization rate was lower in the NHD arm. Post-HD body weight and serum albumin levels increased in the NHD group. Use of antihypertensive medications and erythropoietin declined in the NHD group. In the NHD group, left atrium and left ventricular end-diastolic diameters decreased and left ventricular mass index regressed. Both use of phosphate binders and serum phosphate level decreased in the NHD group. Cognitive functions improved in the NHD group, and quality of life scores deteriorated in the CHD group. CONCLUSIONS: Eight-hour thrice-weekly in-centre NHD provides morbidity and possibly mortality benefits compared to conventional 4-h HD.

The benefit of salt restriction in the treatment of end-stage renal disease by haemodialysis.

BACKGROUND: Most haemodialysis (HD) centres use anti-hypertensive drugs for the management of hypertension, whereas some centres apply dietary salt restriction strategy. In this retrospective cross-sectional study, we assessed the effectiveness and cardiac consequences of these two strategies. METHODS: We enrolled all patients from two dialysis centres, who had been on a standard HD programme at the same centre for at least 1 year. All patients underwent echocardiographic evaluation. Clinical data were obtained from patients' charts. Centre A (n = 190) practiced 'salt restriction' strategy and Centre B (n = 204) practiced anti-hypertensive-based strategy. Salt restriction was defined as managing high blood pressure (BP) via lowering dry weight by strict salt restriction and insistent ultrafiltration without using anti-hypertensive drugs. RESULTS: There was no difference regarding age, gender, diabetes, history of cardiovascular disease and efficiency of dialysis between centres. Antihypertensive drugs were used in 7% of the patients in Centre A and 42% in Centre B (P < 0.01); interdialytic weight gain was significantly lower in Centre A (2.29 +/- 0.83 kgversus 3.31 +/- 1.12 kg, P < 0.001). Mean systolic and diastolic blood pressures were similar in the two centres. However, Centre A had lower left ventricular (LV) mass (indexed for height(2.7): 59 +/- 16 versus 74 +/- 27 g/m(2.7), P < 0.0001). The frequency of LV hypertrophy was lower in Centre A (74% versus 88%, P < 0.001). Diastolic and systolic functions were better preserved in Centre A. Intradialytic hypotension (hypotensive episodes/100 patient sessions) was more frequent in Centre B (11 versus 27, P <0.01). CONCLUSIONS: This cross-sectional study suggests that salt restriction and reduced prescription of antihypertensive drugs may limit LV hypertrophy, better preserve LV functions and reduce intradialytic hypotension in HD patients.

[Evaluation of early alterations in transmitral diastolic flow and tissue Doppler findings of the Basal segments of both ventricles in early period after coronary angioplasty]. / Koroner anjiyoplasti sonrasi erken dönemde mitral diyastolik akim ve her iki ventrikül bazal bölge doku Doppler bulgularindaki degisikliklerin degerlendirilmesi.

OBJECTIVE: Diastolic dysfunction of the left ventricle (LV) appears to be the earliest manifestation of myocardial ischemia. Experimental and clinical studies have shown that both early and late improvements of diastolic function occur after percutaneous transluminal coronary angioplasty (PTCA). Because of the limited utility of transmitral flow profile in the evaluation of the LV diastolic function, recently, assessment of myocardial velocities by Doppler tissue imaging is gaining importance. The aim of this study was to determine the utility of pulsed wave tissue Doppler (PWTD) pattern from the mitral and tricuspid annulus motion in the evaluation of early alterations of the LV diastolic function after revascularization with PTCA in patients with coronary artery disease. METHODS: Pulsed wave tissue Doppler in combination with conventional pulsed-Doppler indices were used to evaluate LV diastolic function before and 24 hours after PTCA. Examinations were performed on 31 patients with chronic ischemic heart disease underwent elective first PTCA. As conventional Doppler indices, early diastolic mitral velocity (e), and its deceleration time (Edt), isovolumic relaxation time (IVRT), late diastolic mitral velocity (a) were measured. Using 2-dimensional echocardiography four chamber apical window, mitral annulus septal and lateral site and tricuspid annulus lateral site were viewed, and PWTD velocity profile were used to calculate; early diastolic maximum velocity and time, late diastolic maximum velocity and time, systolic maximum velocity and time, IVRT and isovolumic contraction time (IVCT) from each site. RESULTS: After PTCA only 2 transmitral conventional pulsed-Doppler indices were changed significantly (IVRT; from 139.7+/-22.2 msec to 120.0+/-15.9 msec, p=0.0001; Edt; from 279+/-11 msec to 248+/-36 msec, p=0.005). However, PWTD (mitral annulus lateral site) analyses showed significant improvement in most of the diastolic parameters: e/a ratio - from 0.80+/-0.26 to 0.89+/-0.22, p=0.012; s wave - from 11.6+/-3.1 cm/sec to 13.2+/-3.6 cm/sec, p=0.03; IVRT - from 130+/-37 msec to 108+/-29 msec, p=0,0001; IVCT - from 84.1+/-19.2 msec to 75.6+/-12.2 msec, p=0.02. Similar significant changes were also observed in the PWTD diastolic parameters of both the mitral annulus septal and tricuspid annulus sites. Peak systolic velocities that reflect the LV systolic functions, of three annular sites significantly improved early after PTCA, however ejection fraction was not changed as much as tissue Doppler parameters (s maximum velocity before PTCA: 11.7+/-3.1 cm/sec versus 13.2+/-3.6 cm/sec after PTCA, p=0.03). CONCLUSION: Tissue Doppler indices of the mitral annulus reflecting both the diastolic and systolic functions, improve early after successful PTCA in patients with coronary artery disease.