Significance of Wedensky Modulation testing in the evaluation of non-invasive risk stratification for ventricular tachyarrhythmia in patients with coronary artery disease and implantable cardioverter-defibrillator.
OBJECTIVE
Evaluation of the significance of the Wedensky Modulation (WM) examination for ventricular tachyarrhythmias (VT) in patients with coronary artery disease and implantable cardioverter-defibrillator therapy (ICD).


METHODS
Prospective, single-centre study conducted from 2004 to 2006.


METHODS
University of Bonn, Department of Medicine - Cardiology, Bonn, Germany.


METHODS
37 consecutive patients with coronary artery disease receiving an ICD for primary or secondary prevention.


METHODS
Correlation of a positive WM-Index (WMI) with established non-invasive Holter parameter, the occurrence of VT after ICD implantation with regard to primary or secondary prevention, and inducibility of VT during electrophysiological (EP) studies.


RESULTS
The WMI was positive in 15 patients (67 (SD 8) years, 31% (SD 12%) EF) and showed significant correlation with heart rate variability (standard deviation of normal to normal intervals (SDNN): 143 (SD 80) ms vs 102 (SD 29) ms, p = 0.04, r = 0.45; total power (TP). 11 885 (SD 19 674) ms(2) vs 2229 (SD 1779) ms(2), p = 0.03, r = 0.384; very low frequency component (VLF): 2777 (SD 3039) ms(2) vs 1184 (SD 565) ms(2), p = 0.03; low frequency component (LF): 2955 (SD 5734) ms(2) vs 468 (SD 725) ms(2), p = 0.05, r = 0.375; high frequency component (HF): 4885 (SD 9939) ms(2) vs 382 (SD 609) ms(2), p = 0.05, r = 0.315) and turbulence (turbulence onset (TO): -0.002 (SD 0.008) vs +0.005 (SD 0.01), p = 0.05, r = 0.301; turbulence slope (TS): 3.4 (SD 3.1) vs 1.7 (SD 1.5), p = 0.04, r = 0.419). The positive predictive value of the WMI considering the inducibility of VT during EP testing was 100%. Those patients who received an ICD for primary prevention showed a higher WMI (p = 0.049) than the secondary prevention group. With respect to the occurrence of adequate VT episodes, a negative WM test result demonstrated a negative predictive value of 95%.


CONCLUSIONS
The data presented show that the WM-Index predicts VT inducibility during EP testing and indicates a high negative predictive value regarding the occurrence of VT.
Elgarhi
N
N
Department of Medicine - Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany.
Kreuz
J
J
Balta
O
O
Nickenig
G
G
Hoium
H
H
Lewalter
T
T
Schwab
J Otto
JO
D000368:Aged; D003324:Coronary Artery Disease / Q000150:complications*; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control; D017147:Defibrillators, Implantable; D004558:Electric Stimulation / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy