Diagnostic accuracy of noninvasive coronary angiography in patients after bypass surgery using 64-slice spiral...

Area of Science:

• Cardiovascular Imaging
• Radiology
• Medical Diagnostics

Background:

• Multidetector computed tomographic angiography (MDCT) is recognized for detecting coronary artery bypass graft (CABG) occlusions and stenoses.
• However, its validation for assessing native coronary arteries alongside CABG has been limited.

Purpose of the Study:

• To validate the use of 64-slice MDCT for assessing both coronary artery bypass grafts (CABG) and native coronary arteries.
• To determine the sensitivity and specificity of MDCT in detecting significant stenoses in these vessels.

Main Methods:

• Fifty patients with 138 CABG were investigated using 64-slice MDCT (0.6-mm collimation, 32 detector rows).
• MDCT assessment of CABG and native coronary arteries (>1.5 mm diameter) for stenoses (> or = 50% diameter reduction) was compared with quantitative coronary angiography.
• Graft patency and stenosis presence were evaluated.

Main Results:

• MDCT successfully evaluated all CABG, correctly classifying them as occluded (n=38) or patent (n=100).
• Sensitivity for stenosis detection in patent grafts was 100% with 94% specificity.
• For native coronary arteries, per-segment sensitivity was 86% and specificity 76%; for nongrafted arteries, sensitivity was 86% and specificity 90%.

Conclusions:

• Sixty-four-slice MDCT enables comprehensive evaluation of bypass grafts.
• MDCT is effective in assessing native coronary arteries for the presence of stenosis.
• The technique offers high diagnostic performance for both CABG and native coronary artery assessment.