title: Randomized Controlled Trial of Individualized Dialysate Cooling for Cardiac Protection in Hemodialysis Patients.
abstract: OBJECTIVE
  Cardiovascular disease is the most common cause of death in patients on hemodialysis (HD). HD-associated cardiomyopathy is appreciated to be driven by exposure to recurrent and cumulative ischemic insults resulting from hemodynamic instability of conventionally performed intermittent HD treatment itself. Cooled dialysate reduces HD-induced recurrent ischemic injury, but whether this confers long-term protection of the heart in terms of cardiac structure and function is not known.
  
  
  METHODS
  Between September 2009 and January 2013, 73 incident HD patients were randomly assigned to a dialysate temperature of 37°C (control) or individualized cooling at 0.5°C below body temperature (intervention) for 12 months. Cardiac structure, function, and aortic distensibility were assessed by cardiac magnetic resonance imaging. Mean between-group difference in delivered dialysate temperature was 1.2°C±0.3°C. Treatment effects were determined by the interaction of treatment group with time in linear mixed models.
  
  
  RESULTS
  There was no between-group difference in the primary outcome of left ventricular ejection fraction (1.5%; 95% confidence interval, -4.3% to 7.3%). However, left ventricular function assessed by peak systolic strain was preserved by the intervention (-3.3%; 95% confidence interval, -6.5% to -0.2%) as was diastolic function (measured as peak diastolic strain rate, 0.18 s(-1); 95% confidence interval, 0.02 to 0.34 s(-1)). Reduction of left ventricular dilation was demonstrated by significant reduction in left ventricular end-diastolic volume (-23.8 ml; 95% confidence interval, -44.7 to -2.9 ml). The intervention was associated with reduced left ventricular mass (-15.6 g; 95% confidence interval, -29.4 to -1.9 g). Aortic distensibility was preserved in the intervention group (1.8 mmHg(-1)×10(-3); 95% confidence interval, 0.1 to 3.6 mmHg(-1)×10(-3)). There were no intervention-related withdrawals or adverse events.
  
  
  CONCLUSIONS
  In patients new to HD, individualized cooled dialysate did not alter the primary outcome but was well tolerated and slowed the progression of HD-associated cardiomyopathy. Because cooler dialysate is universally applicable at no cost, the intervention warrants wider adoption or confirmation of these findings in a larger trial.
authors.affiliation: Institute of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom; Division of Medical Sciences, University of Nottingham, Nottingham, United Kingdom; Department of Renal Medicine, Royal Derby Hospital, Derby, United Kingdom;
authors.forename: Aghogho
authors.initials: A
authors.lastname: Odudu
authors.affiliation: Division of Medical Sciences, University of Nottingham, Nottingham, United Kingdom; Department of Renal Medicine, Royal Derby Hospital, Derby, United Kingdom;
authors.forename: Mohamed Tarek
authors.initials: MT
authors.lastname: Eldehni
authors.affiliation: Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom; National Institute for Health Research Leicester Cardiovascular Biomedical Research Unit, Leicester, United Kingdom; and.
authors.forename: Gerry P
authors.initials: GP
authors.lastname: McCann
authors.affiliation: Division of Nephrology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Canada cmcint48@uwo.ca.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: McIntyre
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001011:Aorta / Q000503:physiopathology; D009202:Cardiomyopathies / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D003080:Cold Temperature; D004739:England; D005260:Female; D015312:Hemodialysis Solutions / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects / Q000379:methods*; D012307:Risk Factors; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D059289:Vascular Stiffness; D016277:Ventricular Function, Left
chemical_list: D015312:Hemodialysis Solutions
keywords: clinical trial; heart disease; hemodialysis