혈액투석 전후의 QT 간격과 전해질 변화에 대한 분석

Changes in the QT Interval and QT Dispersion Before and After Hemodialysis: Role of Peridialytic Electrolyte Changes

Background: End-stage renal failure patients are reported to have an increased risk of sudden cardiac death that may occur in the immediate postdialysis period. Clinical and experimental data have shown that increased QT dispersion is associated with severe ventricular arrhythmias and sudden cardiac death. Therefore, the purpose of this study was to assess the effect of hemodialysis on QT and corrected QT(QTc) interval and QT dispersion in chronic hemodialyzed patients compared to noram 1 subjects and to evaluate the effect of electrolyte changes between the predialysis and postdialysis phases on these parameters. Methods: Thirty-one patients with end-stage renal failure on long-term HD (19 men, 12 women, >3 months) were included in this study. Thirty control subjects with a similar age and normal renal function enrolled from this hospital. Serum concentrations of Na+，K+, Cl , Mg2+, Ca2+, P , BUN, creatinine, ESR, CRP, ferritin, and homocysteine were monitored and QT, QTc intervals and dispersion were measured from 12-lead ECG in predialysis and postdialysis phases. Result: The hemodialyzed patients had an increased predialysis QT, QTd and QTcd compared to normal subjects. Also, QT, QTd and QTcd were increased significantly during the postdialysis period. The serum K+ was significantly decreased, whereas the Ca + concentration was significantly increased after HD compared to predialysis values. There was correlation between the QT dispersion and serum electrolyte change(K+，Ca2+)(p<0.05). Conclusions: QT interval and QT dispersion are easily obtainable, noninvasive, simple, inexpensive, and widely available methods of risk of arrhythmias and sudden death in uremic patients receiving chronic dialysis. The association between serum electrolyte changes and QT measurements might provide new insights into the evaluation of the ionic bases involed in inhomogeneous ventricular repolarization.