CT vs conventional angiography in unselected patients with suspected coronary heart disease

BACKGROUND: To provide confirmatory evidence that the accuracy of MSCT coronary angiography is comparable to that of conventional coronary angiography. METHOD: 19 patients who had both MSCT and conventional coronary angiography were included in our study. The mean age of our patients was 62.3 (SD 7.7) and 42% of our patients were female. The coronary vascular tree was subdivided into 13 segments (modified from the 16-segment AHA classification). The grade of disease was classified into 1 of 6 categories; (1)0-50% stenosis; (2) 50-75% stenosis; (3) 75-99% stenosis; (4) Occluded; (5) aneurysmal; (6) fistula. The results of the imaging studies were analysed by two radiologists, who were blinded to the clinical data. RESULTS: A total of 172 coronary artery segments were visualised on both CT and conventional angiography. There is excellent statistical correlation between the appearance of the coronary arteries on MSCT and conventional angiography, as determined by Spearmans test (r=0.727, P<0.0001). MSCT coronary angiography had a sensitivity of 80.0%, specificity of 95.9%, NPV of 97.9% and PPV of 66.7%. CONCLUSION: The specificity and NPV from our study are similar to those obtained by previous researchers. This study confirms that a negative CT coronary angiogram is useful to rule out the presence of significant coronary heart disease.