Diurnal Corrected QT Interval and QT Dispersion Variation in Non-alcoholic Cirrhotic Patients and Healthy Control: A Case-Control Study, Iran

Background: Cirrhosis could lead to a long corrected QT (QTc) interval in a subgroup of patients, but there are spare data on its diurnal variation. Objectives: The present study aimed to determine the diurnal variation of QTc interval and its relationship to heart rate and blood pressure variation during 24-hour Holter-monitoring in non-alcoholic cirrhosis in comparison with the healthy controls. Methods: The study population comprised 15 patients with non-alcoholic cirrhosis and 15 healthy subjects, undergoing 24-hour electrocardiogram (ECG), heart rate, and blood pressure monitoring. The mean QT interval, mean QTc, maximum and minimum QT, QT dispersion (QT disp), heart rate, and mean arterial blood pressure were measured for each person for 24 hours. Liver stiffness measurement (LSM) was performed by FibroScan® 502 machine (EchoSense, Paris, France, 5 MHz). The results were demonstrated as percentages and mean ± SD. P value ≤ 0.05 was considered significant. Results: Mean QTc was significantly higher in cirrhosis (438 ms) than healthy controls (401.7 ms) (P = 0.03). The mean heart rate was significantly different in cirrhotic patients (79.6 ± 2.9/bpm) compared to healthy controls (72.47 ± 2.0/bpm) (P = 0.05). Conclusions: In this study, QTc was prolonged and increased with the severity of cirrhosis, and its diurnal variation in cirrhosis was different from healthy subjects.