Defining The Role Of Dialysate Magnesium In Arrhythmogenicity On Dialysis

Heart disease is a major cause of illness and death among patients on dialysis. Changes in the heart's rhythm and sudden cardiac death are also important problems in this group. Abnormal rhythm can occur during hemodialysis. During dialysis, the blood comes in contact with a solution called dialysate. This solution contains minerals like calcium, potassium and magnesium. Some studies have indirectly suggested that lower magnesium in dialysis patients protects them from having rhythm problems. Factors that increase the chance for the development of abnormal rhythms can be indirectly assessed by evaluating the electrocardiogram (EKG). This is done by measuring the distance between the wave forms on the EKG. One of these is called the QT interval. QT dispersion is a value derived from the QT interval. A long QT interval is thought to make an individual more prone to having abnormal heart rhythms. Therefore it is planned to study the effect of low levels of magnesium in the dialysate on QT interval and dispersion and the tendency for rhythm change. QT interval changes will be compared during dialysis with low magnesium with QT interval changes during dialysis with normal magnesium. This will be a cross over trial including 24 adult male and female patients on chronic hemodialysis. Subjects will be studied during two of their regular dialysis sessions, the only difference being the amount of magnesium in the dialysate. QT interval and QT dispersion will be calculated from the EKG recordings before and after each dialysis session. The results of this study will lead to a better understanding of cardiovascular risks in patients undergoing chronic dialysis and may offer a potentially novel strategy to reduce the risk of abnormal heart rhythms risk during dialysis.