Stress-ECG vs. CT coronary angiography for the diagnosis of coronary artery disease: a "real-world" experience.
OBJECTIVE
This study aimed to evaluate the diagnostic accuracy of stress electrocardiogram (ECG) and computed tomography coronary angiography (CTCA) for the detection of significant coronary artery stenosis (> or =50%) in the real world using conventional CA as the reference standard.


METHODS
A total of 236 consecutive patients (159 men, 77 women; mean age 62.8+/-10.2 years) at moderate risk and with suspected coronary artery disease (CAD) were enrolled in the study and underwent stress ECG, CTCA and CA. The CTCA scan was performed after i.v. administration of a 100-ml bolus of iodinated contrast material. The stress ECG and CTCA reports were used to evaluate diagnostic accuracy compared with CA in the detection of significant stenosis > or =50%.


RESULTS
We excluded 16 patients from the analysis because of the nondiagnostic quality of stress ECG and/or CTCA. The prevalence of disease demonstrated at CA was 62% (n=220), 51% in the population with comparable stress ECG and CTCA (n=147) and 84% in the population with equivocal stress ECG (n=73). Stress ECG was classified as equivocal in 73 cases (33.2%), positive in 69 (31.4%) and negative in 78 (35.5%). In the per-patient analysis, the diagnostic accuracy of stress ECG was sensitivity 47%, specificity 53%, positive predictive value (PPV) 51% and negative predictive value (NPV) 49%. On stress ECG, 40 (27.2%) patients were misclassified as negative, and 34 (23.1%) patients with nonsignificant stenosis were overestimated as positive. The diagnostic accuracy of CTCA was sensitivity 96%, specificity 65%, PPV 74% and NPV 94%. CTCA incorrectly classified three (2%) as negative and 25 (17%) as positive. The difference in diagnostic accuracy between stress ECG and CTCA was significant (p<0.01).


CONCLUSIONS
CTCA in the real world has significantly higher diagnostic accuracy compared with stress ECG and could be used as a first-line study in patients at moderate risk.
Maffei
E
E
Dipartimento di Radiologia e Cardiologia, Azienda Ospedaliero-Universitaria di Parma, Parma, Italy.
Palumbo
A
A
Martini
C
C
Cuttone
A
A
Ugo
F
F
Emiliano
E
E
Menozzi
A
A
Vignali
L
L
Brambilla
V
V
Coruzzi
P
P
Weustink
A
A
Mollet
N
N
Ardissino
D
D
Reverberi
C
C
Crisi
G
G
Cademartiri
F
F
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D003937:Diagnosis, Differential; D004562:Electrocardiography / Q000379:methods*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
D003287:Contrast Media