For the first time in patients presenting with MI symptoms, CT imaging of the coronary arteries has been found to be equally predictive of the necessity to proceed with invasive interventions (either bypass surgery or angioplasty) as coronary angiography.
The study’s initial findings were presented last November at the American Heart Association’s Scientific Sessions, but updated data was released this week in the online edition of the NEJM in advance of the study’s expected completion in 2009.
From the study abstract:
Background The accuracy of multidetector computed tomographic (CT) angiography involving 64 detectors has not been well established.
Methods We conducted a multicenter study to examine the accuracy of 64-row, 0.5-mm multidetector CT angiography as compared with conventional coronary angiography in patients with suspected coronary artery disease. Nine centers enrolled patients who underwent calcium scoring and multidetector CT angiography before conventional coronary angiography. In 291 patients with calcium scores of 600 or less, segments 1.5 mm or more in diameter were analyzed by means of CT and conventional angiography at independent core laboratories. Stenoses of 50% or more were considered obstructive. The area under the receiver-operating-characteristic curve (AUC) was used to evaluate diagnostic accuracy relative to that of conventional angiography and subsequent revascularization status, whereas disease severity was assessed with the use of the modified Duke Coronary Artery Disease Index.
Results A total of 56% of patients had obstructive coronary artery disease. The patient-based diagnostic accuracy of quantitative CT angiography for detecting or ruling out stenoses of 50% or more according to conventional angiography revealed an AUC of 0.93 (95% confidence interval [CI], 0.90 to 0.96), with a sensitivity of 85% (95% CI, 79 to 90), a specificity of 90% (95% CI, 83 to 94), a positive predictive value of 91% (95% CI, 86 to 95), and a negative predictive value of 83% (95% CI, 75 to 89). CT angiography was similar to conventional angiography in its ability to identify patients who subsequently underwent revascularization: the AUC was 0.84 (95% CI, 0.79 to 0.88) for multidetector CT angiography and 0.82 (95% CI, 0.77 to 0.86) for conventional angiography. A per-vessel analysis of 866 vessels yielded an AUC of 0.91 (95% CI, 0.88 to 0.93). Disease severity ascertained by CT and conventional angiography was well correlated (r=0.81; 95% CI, 0.76 to 0.84). Two patients had important reactions to contrast medium after CT angiography.
Conclusions Multidetector CT angiography accurately identifies the presence and severity of obstructive coronary artery disease and subsequent revascularization in symptomatic patients. The negative and positive predictive values indicate that multidetector CT angiography cannot replace conventional coronary angiography at present. (ClinicalTrials.gov number, NCT00738218
More from Healthimaging.com: NEJM: CorE 64 study affirms 64-slice CT as cardiac cath alternative
Abstract: Diagnostic Performance of Coronary Angiography by 64-Row CT NEJM Volume 359:2324-2336
Flashbacks: Aquilion 64 ; Sensation Cardiac 64; Sensation 64 CT scanner; Aquilion beta 256; AquilionONE CT from Toshiba Cleared by FDA; Brilliance 64-slice CT Scanner by Philips; The Precedence 64-slice SPECT/CT; Biograph 64 PET/CT System
Image credit: Wellcome images: Illustration depicting the concept of ‘heart pain’ in angina pectoris….
