Quantitative relation of electrocardiographic and angiocardiographic measures of risk in patients with coronary atherosclerosis. Simvastatin/Enalapril Coronary Atherosclerosis Trial (SCAT) Investigators.
OBJECTIVE
To correlate angiocardiographic and electrocardiographic (ECG) measures of risk in coronary artery disease (CAD) patients.


METHODS
Baseline substudy of the Simvastatin/Enalapril Coronary Atherosclerosis Trial (SCAT), a 2 x 2 factorial, randomized, controlled trial of CAD regression.


METHODS
One hundred and twenty-three CAD patients, 113 males and 10 females; average age, 59 years.


METHODS
Bivariate correlations of multiple quantitative measures of epicardial coronary angiographic luminal narrowing (quantitative coronary angiography [QCA]) and body surface ECG maps of the sum of the decrease in the potential time integral of the ST segment (SST decrease) between rest and symptom-limited exercise and between rest and 1 and 5 mins postexercise recovery.


RESULTS
The average number of epicardial coronary segments analyzed per patient was 12. The mean diameter averaged 2.78 mm; the minimal diameter, 2.01 mm. The mean percentage coronary stenosis averaged 29.6% and the most severe averaged 62.9%. sigma ST decrease averaged -5323 microV.s between rest and peak exercise and recovered slowly, averaging -5117 microV.s at 1 min postexercise and -4562 microV.s at 5 mins. No QCA measure correlated with any ECG variable (range of r, 0.002 to -0.179; not significant).


CONCLUSIONS
Among CAD patients there are no close, or causal, relations between angiographic measures of anatomic epicardial coronary atherosclerosis and ECG functional measures of exercise-induced myocardial ischemia. These data suggest that demonstrated values of stress ECG and coronary angiography for the prediction of clinical risk in CAD patients are largely independent of each other.
Teo
K K
KK
Department of Medicine, University of Alberta, Edmonton. kkt@tachy.uah.ualberta.ca
Burton
J R
JR
DeAlmeida
J
J
Dolezsar
S
S
Montague
P A
PA
Dzavik
V
V
Tymchak
W J
WJ
Taylor
D A
DA
Montague
T J
TJ
D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D004562:Electrocardiography; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic; D012306:Risk