Inappropriate ICD shocks do not induce pro-arrhythmic electrocardiographic changes in men.
OBJECTIVE
Longer-term electrocardiographic effects of multiple inappropriate ICD shocks were investigated to study their hypothesized pro-arrhythmic potential.


METHODS
Thirteen male patients with ischemic cardiomyopathy who received ≥2 inappropriate shocks within 24 h and for whom 12-lead ECGs were available both before and within 72h after the inappropriate shocks were analyzed. Exclusion criteria included continuous ventricular pacing, underlying AF, events within 6 weeks after lead implantation and concomitant acute medical problems.


RESULTS
A total of 149 inappropriate shocks (mean 11 ± 19) were received. There were no significant differences in any of the measured intervals or morphological indices, nor was there a correlation between the "before-after" differences and the number of shocks received. Non-significant changes showed Percentage of Loop Area increase and relative T-wave Residuum decrease while the opposite changes have previously been associated with arrhythmic risk.


CONCLUSIONS
No potentially pro-arrhythmic electrocardiographic changes were found 19 h after multiple inappropriate shocks.
a Department of Cardiovascular Sciences , University of Leuven , Leuven , Belgium.|b Department of Clinical Cardiology , University Hospitals Leuven , Leuven , Belgium.
Bert
B
Vandenberk
c National Heart and Lung Institute, Imperial College , London , England.
Katerina
K
Hnatkova
d Department of Electrical Engineering (ESAT), STADIUS Center for Dynamical Systems, Signal Processing and Data Analytics , University of Leuven , Leuven , Belgium.|e iMinds, Medical IT , Leuven , Belgium.
Griet
G
Goovaerts
a Department of Cardiovascular Sciences , University of Leuven , Leuven , Belgium.|b Department of Clinical Cardiology , University Hospitals Leuven , Leuven , Belgium.
Christophe
C
Garweg
a Department of Cardiovascular Sciences , University of Leuven , Leuven , Belgium.|b Department of Clinical Cardiology , University Hospitals Leuven , Leuven , Belgium.
Joris
J
Ector
d Department of Electrical Engineering (ESAT), STADIUS Center for Dynamical Systems, Signal Processing and Data Analytics , University of Leuven , Leuven , Belgium.|e iMinds, Medical IT , Leuven , Belgium.
Sabine
S
Van Huffel
c National Heart and Lung Institute, Imperial College , London , England.
Marek
M
Malik
a Department of Cardiovascular Sciences , University of Leuven , Leuven , Belgium.|b Department of Clinical Cardiology , University Hospitals Leuven , Leuven , Belgium.
Rik
R
Willems
D000200:Action Potentials; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D009202:Cardiomyopathies / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004554:Electric Countershock / Q000009:adverse effects* / Q000295:instrumentation*; D004562:Electrocardiography; D004597:Electroshock; D004867:Equipment Design; D004868:Equipment Failure; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
Electrocardiography; implantable cardioverter-defibrillator; inappropriate shocks