QT interval in CKD and haemodialysis patients

Cardiovascular (CV) disease is the leading cause of morbidity and mortality in chronic kidney disease (CKD) patients. Although about half of the deaths are due to CV causes, only a minority are directly linked to myocardial infarction and it is estimated that cardiac arrest or cardiac arrhythmias account for about a quarter of all deaths registered in dialysis patients. Thus, simple non-invasive tools such as electrocardiogram (ECG) may detect those patients at increased risk for arrhythmias. The QT interval on the standard 12-lead ECG is the time from ventricular depolarization (Q wave onset) to cardiac repolarization completion (end of the T wave) and represents a marker of cardiac repolarization defects. Numerous studies suggest a direct association between QT abnormalities and poor prognosis in the general population, CKD patients and dialysis patients. Of note, multivariable adjustments for different traditional and CKD-specific risk factors for CV events attenuate but do not cancel these associations. We herein review the clinical significance of simple non-invasive tools such as the QT tract on ECG for detecting those patients at increased risk of CV event and possibly for treatment individualization.