Explanation:
DQT dispersion, defined as the difference in duration between the longest and shortest QT interval on an electrocardiogram, is a method of approximating repolarization abnormalities. QT dispersion has been shown to independently predict cardiovascular mortality in incident dialysis patients. Intradialytic QT dispersion has been demonstrated to be inversely related to dialysate calcium composition-prolongation of QTc may be also dependent on highbicarbonate concentration in dialysate;
Dialysate contain–ing low concentrations of K and Ca may induce prolonga–tion of QTc. Excessive lowering of serum Ca during the HD session by a low dialysate Ca concentration may be associated with more frequent episodes of hypotension and cardiac rhythm disturbances in association with concomitant hypokalemia seen towards end of dialysis when using a low K bath -prolongation of QTc may be also dependent on high bicarbonate concentration in dialysate; prolonged QTc was still present long after the end of dialysis, indicating that forceful correction of uremic acidosis may be harmful.In fact the influence of alkalosis to reduce ionized Ca has been well known for a long time . Therefore, the ef–fects on ionized Ca of using a high bicarbonate dialysis bath, are more intense when Ca in the bath of dialysis is lower. there is no unanimously accepted cutoff for risk regarding QTc interval duration; the value of 440 milliseconds is usu–ally accepted as the limit.Drugs like amiodarone, zofran, levofloxacin, and lexapro increase QT prologation
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