Diagnostic accuracy of 64-slice multi-detector CT in assessment of coronary artery stenosis.

Objective: To investigate the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of noninvasive coronary artery assessment. Methods: A total of 559 patients with suspected coronary artery disease had undergone noninvasive coronary CT angiography. The 78 patients (55 men and 23 women) had consecutively received a 64-slice multi-detector row CT (MDCT) examination, as well as invasive coronary angiography, within the three months period of the study. The coronary CT angiography was retrospectively reviewed by two radiologists. The degree of coronary stenosis was compared with invasive conventional angiography. Results: The coronary CT angiography of 1,032 segments in 78 patients were evaluated. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of coronary CT angiography for the detection of coronary artery stenosis were 71.1%, 98.4%, 89.4%, 94.7%, and 94.0% respectively. Conclusion: Coronary CT angiography using a 64-slice MDCT implies the reliable detection of coronary artery stenoses with high diagnostic accuracy.

Assessment of coronary artery stenosis with 16 slices multidetector CT.

Objective: To investigate the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of noninvasive coronary computer tomography (CT) for assessment of coronary arteries. Methods: The total of 330 patients who were suspected to have coronary artery disease underwent noninvasive coronary CT angiography. The 26 patients (male 14: female 12) had consecutively undergone a 16 slices multi-detector row CT, as well as invasive coronary angiography, within a 3 months period. The coronary CT angiography was retrospectively reviewed by two radiologists. The degree of coronary stenosis was compared with invasive conventional angiography. Results: The coronary CT angiography of 306 segments in 26 patients was evaluated. The 306 segments were divided into proximal 155 branches and distal 151 branches. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of coronary CT angiography for coronary artery stenosis were 76.9%, 91.7%, 65.6%, 95.1%, and 89.2% respectively. The sensitivity and specificity of proximal coronary artery stenosis 155 segments were 85.7%, and 90.8%, respectively. The sensitivity and specificity for 151 distal branches were 58.8% and 92.5%, respectively. Conclusion: Coronary CT angiography using 16 slices multi-detector row CT allows for the reliable detection of coronary artery stenoses with a high diagnostic accuracy.

Influence of heart rate on image quality to identify the best cardiac phase in 16-slice coronary CT angiography.

OBJECTIVE: To identify the best cardiac phase in different patient's heart rate on 16-slice coronary CT angiography. MATERIAL AND METHOD: The patients who had undergone coronary CT angiography with 16 multi-detector rows CT at Siriraj Hospital between September 2003 and August 2004. For each patient, the image reconstruction based on relative timing was performed placed at center of 35% to 85% of the R-R interval with step increments 10%. The authors created six data sets (35%, 45%, 55%, 65%, 75%, and 85% of R-R interval) throughout the cardiac cycle. The coronary arteries were reviewed based on cross-sectional images and reformat images. The authors inspected all data sets and selected the cardiac phase that contained the best image quality for each coronary artery. RESULTS: Five hundred sixty four vessels were evaluated in the 141 patients (83 men, 58 women). The mean patient age was 63.3 +/- 16.7 years (range 4-89 years). Mean patient heart rate was 65.7 +/- 16.5 beats per minute (bpm), range 46-104 bpm. The most coronary arteries were well demonstrated at center of 75% of R-R interval (66.8%). Ninety-eight patients (69.5%) required one phase that provided best overall image quality and motion free delineation for four coronary arteries. Forty-three patients (30.5%) required combination of data from each phase to achieve motion free images. CONCLUSION: The best cardiac phase of evaluate coronary artery in 16 slices coronary CT angiography in the patient's heart rate below 70 bpm is 75% of cardiac cycle (mid to late diastole). In patients with a heart rate 71-80 bpm, the authors required a combination of images from 45% and 75% of cardiac cycle to completely evaluate all coronary arteries. In patients with a heart rate above 80 bpm, 45% of cardiac cycle (end-systole) is the best phase.

Comparison of image quality of coronary CT angiography between 16 and 64 slices MDCT.

OBJECTIVE: To compare the image quality and visibility of coronary arteries that were performed by 16 slices and 64 slices multidetector row CT (MDCT). STUDY DESIGN: Descriptive analysis. MATERIAL AND METHOD: Twenty-eight patients suspected of hearing coronary artery disease had noninvasive coronary CT angiography performed by 16 slices MDCT and 64 slices MDCT Data were retrospectively analyzed and reviewed by two radiologists. Image quality was assessed by using a grading scale from excellent (4) to non-assessable (0) and the rate of displayed coronary branches was calculated. RESULTS: Four hundred twenty coronary CT angiography segments in 28 patients were evaluated. CONCLUSION: Coronary CT angiography using 64 slices multi-detector row CT provides a significantly higher image quality of coronary arteries and their branches compared with 16 slices multi-detector row CT.