Peritoneal dialysis in patients with heart failure.

Both in dialysis patients and non-uremic patients heart failure is associated with an adverse prognosis. In a state of abrupt worsening of cardiac function, acute cardiogenic shock or decompensated congestive heart failure, acute kidney injury may occur, whereas in a more chronic worsening of cardiac function chronic kidney injury may occur. Recently, the term cardiorenal syndrome was adopted and defined as "a pathophysiological disorder of the heart and kidneys whereby acute or chronic dysfunction in one organ may induce acute or chronic dysfunction in the other organ". Despite better treatment techniques and the continuous development of new medications volume overload in patients with cardiorenal syndrome is difficult to treat. Especially treatment of cardiorenal syndrome type I and II is notoriously difficult. Peritoneal dialysis might be, because of the gradual fluid removal, a therapeutic option in these patients. However, data on the effect of peritoneal dialysis in patients with heart failure with fluid overload and/or renal impairment are scarce. In this review, the role of peritoneal dialysis in the treatment cardiorenal syndrome type I, II and IV will be discussed.

Peritoneal dialysis in patients with primary cardiac failure complicated by renal failure.

BACKGROUND/AIMS: Clinical outcome in cardiorenal syndrome type II and treated with peritoneal dialysis (PD). METHODS: Retrospective analysis over a period of 10 years. RESULTS: Twenty-four patients with mean age at start of dialysis of 67 ± 10 years had mean survival on dialysis of 1.03 ± 0.84 years (median survival 1.0 year). The number of hospitalizations for cardiovascular causes were reduced (13.7 ± 26.5 predialysis vs. 3.5 ± 8.8 days/patient/month postdialysis, p = 0.001). Patients who survived longer than the median survival time (n = 12) also had a reduced number of hospitalizations for all causes (3.7 ± 3.8 predialysis vs. 1.4 ± 2.1 days/patient/month postdialysis, p = 0.041), a lower age (62 ± 10 vs. 71 ± 8 years, p = 0.013) and fewer had diabetes (2 vs. 7 patients, p = 0.039), but left ventricular ejection fraction was not different. CONCLUSION: After starting PD for cardiorenal syndrome, hospitalizations for cardiovascular causes were reduced for all patients. Survival after starting PD is highly variable. Age and diabetes seem to be significant prognostic factors, but not left ventricular ejection fraction.

Measurement of hemodialysis vascular access flow using extracorporeal temperature gradients.

A reduction in vascular access flow poses a risk for thrombosis. We present a new technique to measure vascular access flow during dialysis based on extracorporeal temperature gradients, and their changes, on reversing the extracorporeal bloodlines without having to inject an indicator. Fistula temperatures were measured by the blood temperature monitor with normal line position and after manual switching of the bloodlines using the same extracorporeal blood flow. The access flow by our temperature gradient method (TGM) was compared to access flow derived by saline dilution with measurements in the same patients repeated in subsequent weeks. In 70 pairs of TGM and saline dilution measurements in 35 patients, the repeatability of the TGM measurements was not significantly different from that of saline dilution. There was a highly significant correlation between the two techniques with an acceptable confidence level for limits of agreement for the difference between them. It took about 9 min to complete the TGM method and about 5 min for saline dilution. Our studies show that the novel TGM method showed excellent agreement and reproducibility with the saline dilution method without the need for indicator dilution.

Association of serum fetuin-A levels with mortality in dialysis patients.

Calcifying atherosclerosis is an active process, which is controlled by calcification inhibitors and inducers. Fetuin-A, an acute phase glycoprotein, is one of the more powerful circulating inhibitors of hydroxyapatite formation. A prospective multicenter cohort study was initiated to include both hemodialysis (HD) and peritoneal dialysis (PD) patients in an evaluation of the association of serum fetuin-A levels with both cardiovascular (CV) and non-CV mortality. An increase in the serum fetuin-A concentration of 0.1 g/l was associated with a significant reduction in all-cause mortality of 13%. There was a significant 17% reduction in non-CV mortality and a near significant reduction in CV mortality. This association of fetuin-A and mortality rates was comparable in both HD and PD patients even when corrected for factors, including but not limited to age, gender, primary kidney disease, C-reactive protein levels, and nutritional status. We conclude that serum fetuin-A concentrations may be a general predictor of mortality in dialysis patients.

Wall shear stress assessment in the common carotid artery of end-stage renal failure patients.

Under physiological circumstances in the common carotid artery (CCA), mean wall shear stress (WSS), defined as mean wall shear rate (WSR) times local whole blood viscosity (WBV), is maintained at approximately 1.5 Pa. In patients with end-stage renal failure (ESRF) whole blood viscosity is low and it is not unlikely that mean WSS is lower in these patients than in control subjects. Moreover, hemodialysis causes an acute increase in blood viscosity with possible effects on WSS. In this study WSS in the CCA was determined with the Shear Rate Estimating System, an apparatus based on ultrasound, in ESRF patients (n = 13) and in presumed healthy age- and sex-matched control subjects (n = 13). Prior to hemodialysis, mean WSS (0.67 +/- 0.23 Pa) was significantly lower (p < 0.05) in patients with ESRF, due to both a lower WBV (2.80 +/- 0.52 mPa.s) and mean WSR (271 +/- 109 s(-1)), than in the control subjects (mean WSS: 1.24 +/- 0.20 Pa; WBV: 3.20 +/- 0.29 mPa.s; WSR: 387 +/- 51 s(-1)). Hemodialysis induced an increase in WBV (up to 3.71 +/- 1.54 mPa.s, p < 0.01), but mean WSS did not change significantly due to a reciprocal decrease in mean wall shear rate. These findings demonstrate that WSS is lower in hemodialysis patients than in control subjects, and that mean WSS is maintained at this low level despite an acute change in blood viscosity.