TY - JOUR
T1 - QT variability index changes with severity of cardiovascular autonomic neuropathy
AU - Khandoker, Ahsan H.
AU - Imam, Mohammad Hasan
AU - Couderc, Jean Philippe
AU - Palaniswami, Marimuthu
AU - Jelinek, Herbert F.
PY - 2012
Y1 - 2012
N2 - Cardiovascular autonomic neuropathy (CAN) has been frequently postulated to increase susceptibility to ventricular arrhythmias and sudden cardiac death in diabetic patients. The relation between the progression of CAN in diabetes and ventricular repolarization remains to be fully described. Therefore, this study examined QT interval variability and heart rate interbeat variability to identify any alterations of cardiac repolarization in diabetic patients in relation to severity of CAN. Seventy control participants without (CAN-) and 74 patients with CAN (CAN+) were enrolled in this study. Among 74 CAN+ patients, 62 are early CAN+ (eCAN+), and 12 are definite CAN+ (dCAN+) according to autonomic nervous system function tests as described by Ewing. The results showed that the QT variability index (QTVI) was significantly (p < 0.05) higher and positive in the dCAN+ (0.51±1.32) group than in the eCAN+ (-0.39±0.91) and CAN - (-0.54±0.72) groups. The QT variability to heart-rate variability ratio provides a measure of the balance between QT and heart interbeat variability. QTVI was more sensitive in identifying disease progression at all stages. Our study supports the hypothesis that QTVI could be used as a clinical test to identify early CAN and as a marker of CAN progression in diabetic patients and may help physicians in determining the best therapeutic strategy for these patients.
AB - Cardiovascular autonomic neuropathy (CAN) has been frequently postulated to increase susceptibility to ventricular arrhythmias and sudden cardiac death in diabetic patients. The relation between the progression of CAN in diabetes and ventricular repolarization remains to be fully described. Therefore, this study examined QT interval variability and heart rate interbeat variability to identify any alterations of cardiac repolarization in diabetic patients in relation to severity of CAN. Seventy control participants without (CAN-) and 74 patients with CAN (CAN+) were enrolled in this study. Among 74 CAN+ patients, 62 are early CAN+ (eCAN+), and 12 are definite CAN+ (dCAN+) according to autonomic nervous system function tests as described by Ewing. The results showed that the QT variability index (QTVI) was significantly (p < 0.05) higher and positive in the dCAN+ (0.51±1.32) group than in the eCAN+ (-0.39±0.91) and CAN - (-0.54±0.72) groups. The QT variability to heart-rate variability ratio provides a measure of the balance between QT and heart interbeat variability. QTVI was more sensitive in identifying disease progression at all stages. Our study supports the hypothesis that QTVI could be used as a clinical test to identify early CAN and as a marker of CAN progression in diabetic patients and may help physicians in determining the best therapeutic strategy for these patients.
KW - Cardiac autonomic neuropathy (CAN)
KW - cardiac repolarization
KW - heart-rate variability (HRV)
KW - QT liability
KW - repolarization instability
UR - http://www.scopus.com/inward/record.url?scp=84866626883&partnerID=8YFLogxK
U2 - 10.1109/TITB.2012.2205010
DO - 10.1109/TITB.2012.2205010
M3 - Article
C2 - 22929462
AN - SCOPUS:84866626883
SN - 1089-7771
VL - 16
SP - 900
EP - 906
JO - IEEE Transactions on Information Technology in Biomedicine
JF - IEEE Transactions on Information Technology in Biomedicine
IS - 5
M1 - 6287022
ER -