Cardiac Repolarization Abnormalities Among Patients With Various Stages of Chronic Kidney Disease

Abstract

Background Patients with chronic kidney disease (CKD) are at increased risk of life‐threatening cardiovascular arrhythmias. Although these arrhythmias are usually secondary to structural heart diseases that are commonly associated with CKD, a significant proportion of cases with sudden cardiac death have no obvious structural heart disease. This study aims to explore the relationship of cardiac repolarization in patients with CKD and worsening kidney function. Hypothesis There is cardiac repolarization abnormalities among patients with chronic kidney disease. Methods This was a retrospective, chart‐review study of admissions or clinic visits to a university hospital between 2005 and 2010 by patients with a diagnosis of CKD. Inclusion criteria selected patients who had 12‐lead surface electrocardiography (ECG), renal function tests within 24 hours, and transthoracic echocardiography within 6 months. Cases with a documented etiology for the corrected Qt (Qtc) interval prolongation including structural heart disease, QT prolonging drugs, or relevant disease conditions, were excluded. Results Our sample size was 154 ECGs. Two‐thirds of patients with CKD had QTc interval prolongation, and about 20% had a QTc interval >500 ms. QTc interval was significantly different and increased with each successive stage of CKD using the Bazett (P < 0.006) or Fridericia (P = 0.03) formula. QTc interval correlated significantly with serum creatinine (P = 0.01). These finding were independent of age, gender, potassium, and calcium concentrations. Conclusions The progression of CKD resulted in a significant delay of cardiac repolarization, independent of other risk factors. This effect may potentially increase the risk of sudden cardiac death, and may also increase the susceptibility of drug‐induced arrhythmia.

Prevalence and risk factors of acquired long QT syndrome in hospitalized patients with chronic kidney disease

“…The QTc interval increased by an average of 2.9 ms for each milligram increase in serum creatinine 9. Our findings are consistent with previous ones.…”

“…Cardiac repolarization abnormalities are paralleled with the dysfunction of kidney. The QTc interval increases by 2.9 ms with each increased milligram of serum creatinine 9. The extended QTc interval is a hallmark of ventricular arrhythmias, SCD and all-cause mortality 10.…”

Implantable loop recorders in patients with unexplained syncope: Clinical predictors of pacemaker implantation

“…Chronic kidney disease has been shown to be a risk factor of sudden cardiac death caused by cardiomyopathy, myocardial inflammation, myocardial fibrosis, arrhythmias and conduction abnormalities [17,18]. Sudden cardiac death in patients with chronic renal failure is associated with increased levels of inflammatory markers such as high-sensitivity C-reactive protein and interleukin 6 which are both linked to fibrotic changes of the myocardium and the electrical conduction system itself [19].…”

Electronegative LDL-mediated cardiac electrical remodeling in a rat model of chronic kidney disease

“…The progression of CKD has been associated with a significant delay of cardiac repolarization manifested by QTc prolongation, independent of other risk factors or structural heart diseases in humans18. The prolongation of QTc can occur even in patients with early-stage CKD (stage 2)19.…”