Alteration of the QT variability index in end-stage liver disease.
10.4097/kjae.2014.66.3.199
- Author:
In Young HUH
1
;
Eun Sun PARK
;
Kang Il KIM
;
A Ran LEE
;
Gyu Sam HWANG
Author Information
1. Department of Anesthesiology and Pain Medicine, Ulsan University Hospital, Ulsan, Korea. inyoung_huh@uuh.ulsan.kr
- Publication Type:Original Article
- Keywords:
End-stage liver disease;
Head-up tilt;
QT interval;
QT variability index
- MeSH:
Arrhythmias, Cardiac;
Child;
Death, Sudden, Cardiac;
Electrocardiography;
Heart Diseases;
Humans;
Liver Diseases*;
Liver*;
Supine Position
- From:Korean Journal of Anesthesiology
2014;66(3):199-203
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND: A prolonged QT interval can lead to malignant ventricular arrhythmias and sudden cardiac death, and has frequently been found in end-stage liver disease (ESLD). However, myocardial repolarization lability has not yet been fully investigated. We evaluated the QT variability index (QTVI), a marker of temporal inhomogeneity in ventricular repolarization and an abnormality associated with re-entrant malignant ventricular arrhythmias. We determined whether QTVI is affected by the head-up tilt test in ESLD. METHODS: We assessed 36 ESLD patients and 12 control subjects without overt heart disease before and after the 70-degree head-up tilt test. The electrocardiography signal (lead II) was recorded on a computer with an analog-to-digital converter. The RR interval (RRI) and QT interval were measured after recording 5 min of the digitized electrocardiography. Then, the QT intervals were corrected with Bazett's formula (QTc). QTVI was calculated through the following formula: QTVI = log10 [(QTv/QTm2)/(RRIv/RRIm2)], QTv/RRIv: variance of QTI/RRI, QTm/RRIm: mean of QT interval/RRI. RESULTS: Cirrhotic patients exhibited an elevated QTVI. In particular, Child class C patients had a significantly increased QTVI compared to Child class A patients and the control subjects in the supine position. However, the head-up tilt test did not cause a significant difference in QTVI in relation to the severity of ESLD. CONCLUSIONS: Myocardial repolarization lability was significantly altered in end-stage liver disease. Our data suggest that the severity of ESLD is associated with the degree of the alteration in the QT variability index.
