Reduce Cardiovascular Calcifications to Reduce QT Interval in Dialysis

The risk of developing cardiovascular diseases in patients on hemodialysis is higher than in general population. Higher levels of serum phosphate are associated with adverse cardiovascular outcomes, especially in the setting of overt hyperphosphatemia. Given the biological importance of serum phosphorus, it is conceivable that also within the normal range values the higher serum phosphate levels may be associated with the worst outcome. Several paper have shown that vascular calcifications in dialysis patients are associated with increased relative risk of death; it has also been demonstrated in uremic patients that vascular calcifications decrease arterial elasticity. We previously observed that vascular calcification directly correlate with QT interval (QTc) as well as QT dispersion (QTd) in dialysis. Also, QT correction (obtained by the correction of phosphoremia and dyslipidemia) can ameliorate the development of arrhythmia and sudden death. Aim of this study is to evaluate the relationship between vascular calcifications and both QTd increase and mortality in incident hemodialysis patients, and to investigate the efficacy of sevelamer to reduce vascular calcifications and QTd.

Inclusion criteria

• incident patients on haemodialysis (CKD stage 5);
• an informed consent will be provided at the study entry.

Exclusion criteria

• congenital prolongation of QT segment syndrome;
• QTc >440 ms; increased QTd;
• bradycardia <50 bpm;
• sintomatic arrhythmia or any other significant heart problems;
• electrolyte unbalances (especially hypokalemia, hypomagnesemia, hypocalcemia);
• abnormal liver function tests;
• hypothyroidism.