Prolongation of the QT interval in children with liver failure.

BACKGROUND

Alcoholic liver disease has been associated with QT prolongation and sudden cardiac death.

HYPOTHESIS: We evaluated children with hepatic failure to determine whether they have abnormalities of ventricular repolarization.

METHODS

Between October 1990 and January 1996, 38 pediatric patients (mean age 6.5 +/- 7.2 years) underwent evaluation for liver transplantation, including a 12-lead electrocardiogram and an echocardiogram. All patients had normal serum electrolytes, calcium, and magnesium at the time of cardiac evaluation and were not on any medications known to prolong repolarization. Follow-up electrocardiograms were performed on all survivors with QT prolongation following liver transplantation.

RESULTS

Among those evaluated, seven (18%) were noted to have a prolonged QT interval corrected for rate (QTc > 450 ms; range 460-560 ms). All had a structurally normal heart, except one with an atrial and ventricular septal defect. When compared with patients with a normal QT interval, there was no significant difference in serum indices of liver function or indication for liver transplantation. None of the patients developed a ventricular arrhythmia. Two patients with a prolonged QTc died prior to transplant and another died immediately after surgery. All four survivors had normalization of the QTc following liver transplantation.

CONCLUSION

QTc prolongation can be seen in a significant number of children with hepatic failure. While the mechanism is not known, it appears to be reversible following liver transplantation.