Sudden cardiac death after coronary artery bypass grafting is not predicted by signal-averaged ECG.
BACKGROUND
Sudden cardiac death (SCD) is a major cause of death despite successful revascularization in patients with coronary artery disease. The signal-averaged ECG (SAECG) is a sensitive predictor of SCD and could be used in the screening strategy to select patients for prophylactic cardioverter implantation.


METHODS
The SAECG was recorded in 561 patients (mean age: 60 +/- 8.8 years) within 10 days of coronary artery bypass grafting. Signal-averaged ECG was performed with a bandpass filtering of 40 to 250 Hz for more than 250 beats until a noise level of 0.6 microV was achieved. All patients were followed for 5.5 +/- 1.2 years after the procedure.


RESULTS
Preoperative angiographic ejection fraction was at least 60% in 393 patients (72%), 40% to 60% in 126 patients (23%), and 40% or less in 28 patients (5%). There were 34 deaths, 10 of which were SCD. Late potentials were found in a total of 150 patients (27%) and were equally frequent preoperatively and postoperatively and among patients with (30%) and without (27%) SCD. The only predictors for overall mortality were age and a reduced ejection fraction.


CONCLUSIONS
Signal-averaged ECG did not predict prognosis in low-risk patients undergoing coronary artery bypass grafting.
Scharf
C
C
Division of Cardiology, University Hospital, Zurich, Switzerland. christoph.scharf@dim.usz.ch
Redecker
H
H
Duru
F
F
Candinas
R
R
Brunner-La Rocca
H P
HP
Gerber
A
A
Bertel
O
O
Turina
M I
MI
Kiowski
W
W
D001026:Coronary Artery Bypass / Q000009:adverse effects*; D016757:Death, Sudden, Cardiac / Q000453:epidemiology / Q000209:etiology*; D004562:Electrocardiography / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care; D011237:Predictive Value of Tests; D011300:Preoperative Care; D012680:Sensitivity and Specificity; D013997:Time Factors