Randomized Controlled Trial of Individualized Dialysate Cooling for Cardiac Protection in Hemodialysis Patients

Abstract

Background and objectives 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.Design, setting, participants, & measurements 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°C60.3°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 21 ; 95% confidence interval, 0.02 to 0.34 s 21 ). 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 21 310 23 ; 95% confidence interval, 0.1 to 3.6 mmHg 21 310 23 ). There were no intervention-related withdrawals or adverse events.

Cognitive Function Declines Significantly during Haemodialysis in a Majority of Patients: A Call for Further Research

“…With loss of cerebral arterial autoregulation in these patients, it is possible that the haemodynamic stress is transmitted to the cerebral circulation with each haemodialysis session causing recurrent cerebral injury [27]. This effect on coronary circulation is now well established with intradialytic echocardiographic studies demonstrating myocardial stunning [28, 29]. The reduction in cardiac contraction further reduces cerebral micro-perfusion [30].…”

Cooling dialysate during in-center hemodialysis: Beneficial and deleterious effects

“…Since that time, it has become apparent that dialysis itself is a hemodynamic stressor [24] which triggers circulatory stress and consequently damages vasculature in the heart, mesentery, and brain [25][26][27] amongst other organs. Two recent trials demonstrated that cooled dialysate imparts a protective effect in these organs.…”

“…Odudu et al [24] used the same patient population and study design as Eldehni et al [25] to evaluate whether cooled dialysate would have cardioprotective effects dialysis), ultrafiltration (one hour of isolated ultrafiltration in which 50% of the target weight loss was removed followed by three hours of isovolemic dialysis), and cool temperature dialysis in which dialysate was cooled to 35 ℃ (sodium concentration was 140 mEq/L in this group). The results revealed indistinguishable weight losses with each protocol suggesting that the volume of ultrafiltration was consistent across each protocol.…”

Dying to Feel Better

“…Dialysis-induced myocardial ischemia may also act as a trigger for arrhythmias (11). Reduction in hemodynamic instability with a simple dialysis-based intervention can protect against loss of systolic function, diastolic function, and left ventricular hypertrophy (12).…”