title: Vasodilation and Exercise Capacity in Patients with End-Stage Renal Disease: A Prospective Proof-of-Concept Study.
abstract: BACKGROUND
  Previous data have pointed to the fact that vascular function is significantly impaired in patients with end-stage renal disease (ESRD). We aimed to better characterise vasodilation and exercise capacity in both ESRD and chronic heart failure (CHF) patients.
  
  
  METHODS
  A total of 30 ESRD patients (23 male; mean age 45.7 ± 9.9 years) were included in a prospective proof-of-concept study at a tertiary care academic centre. The patients underwent forearm venous plethysmography with post-ischaemic peak blood flow (PF) and flow-dependent flow (FDF) testing as well as cardiopulmonary exercise testing during the morning of the day following the last haemodialysis. After matching for age, gender, and body mass index, the data were compared to 30 patients with CHF and 20 age-matched healthy controls.
  
  
  RESULTS
  PF in ESRD patients was reduced when compared to that in CHF patients (12.5 ± 4.2 vs. 15.6 ± 6.9 ml/100 ml/min; p = 0.048) and healthy controls (26.4 ± 9.3 ml/100 ml/min; p < 0.001). When compared to controls, FDF was significantly reduced in ESRD patients (7.6 ± 3.1 vs. 6.0 ± 2.5 ml/100 ml/min; p = 0.03), but not in CHF patients, whereas resting blood flow did not differ between the ESRD, CHF, and healthy control groups. In contrast to indices of vasodilative capacity, maximum exercise capacity (peakVO2) was higher in ESRD when compared to CHF patients (23.8 ± 7.3 vs. 18.8 ± 5.2 ml/min/kg), but significantly impaired when compared to controls (32.8 ± 6.7 ml/min/kg; p < 0.001).
  
  
  CONCLUSIONS
  In this proof-of-concept study, exercise capacity was relatively preserved, while vasodilative capacity was substantially impaired in ESRD patients. Additional studies are warranted to examine the underlying mechanisms and potential clinical implications of our findings.
authors.affiliation: Medizinische Klinik Kardiologie, DRK-Kliniken Berlin-Köpenick, Berlin, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Habedank
authors.affiliation: Department of Nephrology and Intensive Care Medicine, Berlin, Germany; Department of Intensive Care Medicine, Inselspital, Bern University Hospital, Bern, Switzerland.
authors.forename: Joerg C
authors.initials: JC
authors.lastname: Schefold
authors.affiliation: Department of Cardiology, Applied Cachexia Research, Berlin, Germany.
authors.forename: Carolin
authors.initials: C
authors.lastname: Bernhardt
authors.affiliation: Department of Cardiology, Applied Cachexia Research, Berlin, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Karhausen
authors.affiliation: Department of Cardiology, Applied Cachexia Research, Berlin, Germany; Stroke Research Centre, Charité Campus Virchow-Klinikum, Berlin, Germany.
authors.forename: Wolfram
authors.initials: W
authors.lastname: Doehner
authors.affiliation: Department of Cardiology, Applied Cachexia Research, Berlin, Germany; Department of Cardiology and Pneumology, Innovative Clinical Trials, University of Göttingen, Göttingen, Germany.
authors.forename: Stefan D
authors.initials: SD
authors.lastname: Anker
authors.affiliation: Department of Nephrology and Intensive Care Medicine, Berlin, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Reinke
keywords: Chronic heart failure; Chronic kidney disease; Exercise; Inflammation; Sepsis; Vasodilation