The Wedensky test predicts malignant ventricular arrhythmias after myocardial infarction.
OBJECTIVE
Better tools are needed for detection of future malignant ventricular arrhythmias post myocardial infarct (MI). Wedensky Modulation (WM) is a new semi-invasive method: A short low-amplitude electrical impulse is applied synchronized to the QRS between a precordial and dorsal thoracic patch, and changes in the following QRS-T are registered.


METHODS
A total of 357 (MI) ICD patients underwent WM testing. QRS-T wavelet analysis provided WM Indexes for the QRS complex (WMI-R) and T wave (WMI-T). Outcome was the time to first occurrence of appropriate device therapy for ventricular arrhythmia. Patients were followed at 6-month intervals for 2 years.


RESULTS
No arrhythmia was induced by the testing. Two-year appropriate arrhythmia treatment occurred in 35% (WMI-R positive) versus 25% (WMI-R negative, p = 0.014), and. 45% versus 26% (p = 0.001) for WMI-T positive versus negative. Two-year event rates of WMI-R or WMI-T positive versus WMI-R and WMI-T negative were 36% versus 22% (p = 0.004). In Cox proportional hazard model, the combination of WMI-R and WMI-T was the only statistically significant event predictor (p = 0.003).


CONCLUSIONS
Potentially life-threatening ventricular arrhythmic events could be predicted by the WM test. In combination with other risk factors WMI may be useful in these patients.
Oslo University Hospital , Rikshospitalet , Norway.
Jan Peder
JP
Amlie
Harold
H
Hoium
Per
P
Mathisen
Marek
M
Malik
Peter A
PA
Brady
D000368:Aged; D001145:Arrhythmias, Cardiac; D017147:Defibrillators, Implantable; D005260:Female; D006334:Heart Function Tests; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology; D018579:Patient Selection; D011237:Predictive Value of Tests; D011446:Prospective Studies; D018570:Risk Assessment; D013318:Stroke Volume; D016277:Ventricular Function, Left