Prognostic value of coronary computed tomographic angiography for prediction of cardiac events in patients with suspected coronary artery disease.
OBJECTIVE
We assessed the rate of cardiac events after detection or exclusion of obstructive coronary artery disease (CAD) by coronary computed tomography angiography (CCTA).


BACKGROUND
Several studies have demonstrated a high diagnostic accuracy of CCTA for detection of obstructive CAD compared with invasive angiography, but data regarding the clinical prognostic value of CCTA are limited.


METHODS
In all, 1,256 consecutive patients with suspected CAD undergoing 64-slice CCTA in our institution between October 2004 and September 2006 were observed prospectively for the occurrence of severe cardiac events (cardiac death, myocardial infarction, or unstable angina requiring hospitalization: primary study end point) and all cardiac events (additionally including revascularization >90 days after CCTA). The observed rate of all cardiac events was compared with the event rate predicted by the Framingham risk score. Obstructive CAD was defined as > or = 50% diameter stenosis in any coronary artery.


RESULTS
During a median follow-up of 18 months (interquartile range 14 to 25 months), the overall rates of severe and all cardiac events were 0.6% and 1.8%, respectively. In 802 patients without obstructive CAD, there were 4 cardiac events, of which 1 was severe, whereas in 348 patients with obstructive CAD, there were 17 cardiac events, of which 5 were severe. The difference between the 2 groups was highly significant both for severe events (odds ratio: 17.3, 95% confidence interval: 3.6 to 82.5) and for all cardiac events (odds ratio: 16.1, 95% confidence interval: 7.2 to 36.0; both p < 0.001). The rate of all cardiac events in patients without obstructive CAD was significantly lower than predicted by the Framingham risk score (p = 0.01).


CONCLUSIONS
In patients with suspected CAD, CCTA has a significant prognostic impact on the prediction of cardiac events for the subsequent 18 months. The exclusion of obstructive CAD by CCTA identifies a patient population with an event risk lower than predicted by conventional risk factors.
Hadamitzky
Martin
M
Klinik für Herz-und Kreislauferkrankungen, Deutsches Herzzentrum München, Technische Universität München, Munich, Germany. mhy@dhm.mhn.de
Freissmuth
Barbara
B
Meyer
Tanja
T
Hein
Franziska
F
Kastrati
Adnan
A
Martinoff
Stefan
S
Schömig
Albert
A
Hausleiter
Jörg
J
D000368:Aged; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000150:complications / Q000000981:diagnostic imaging* / Q000401:mortality / Q000628:therapy; D005260:Female; D006331:Heart Diseases / Q000000981:diagnostic imaging / Q000209:etiology* / Q000401:mortality; D006760:Hospitalization; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009204:Myocardial Revascularization; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome