Effect of Haemodialysis on QTc in Newly Diagnosed Chronic Kidney Disease Patients OC15-OC17
Medical College Road, MCC B Block, Davangere-577004, Karnataka, India.
Introduction: Cardiovascular disease and mortality is twice as common in patients with Chronic Kidney Disease (CKD) compared to the general population. The QT interval which depicts ventricular repolarisation, is a crude non-invasive marker of susceptibility to ventricular arrhythmias. Effects of haemodialysis on corrected QT (QTc) interval in newly diagnosed CKD patients is undocumented till date.
Aim: To assess the effect of haemodialysis on QTc in patients with newly diagnosed CKD.
Materials and Methods: This was a prospective cohort study of 50 newly diagnosed CKD patients admitted for their first session of haemodialysis in the Departments of General Medicine and Nephrology, at Bapuji Hospital between October and November 2019. ECGs were recorded before the first and after the third session of haemodialysis. Serum electrolytes (sodium, potassium, chloride, phosphorous and calcium), blood sugar and haemoglobin levels before haemodialysis were recorded. QT interval was calculated and corrected using Bazettâ€™s and Framinghamâ€™s methods. Descriptive statistics, simple and multiple linear regression were used for analysis using Microsoft® Excel.
Results: The mean predialysis QTc was 0.434 seconds and postdialysis QTc was 0.477 seconds. QTc prolongation was observed in 44 (88%) patients (mean=0.042 seconds). The QTc prolongation correlated positively with postdialysis QTc (p=0.00001, Framingham; p=0.0009, Bazett) (RBazett=0.61 and RFramingham=0.74).
Conclusion: Substantial QTc prolongation after three sessions of haemodialysis screens a population that has a greater risk of adverse cardiovascular events. This warrants vigilant cardiac monitoring in patients on haemodialysis.