Data Indicates Superiority of CT for CABG Assessment
A new study published in Radiology indicates that 16- and 64-slice CT has the highest rate of accuracy in the detection of CABG obstruction. The team determined that these two modalities have high rates of both specificity and sensitivity compared to traditional CTA, though 64-slice performs notably better.
Previously published studies which utilized 4- and 8-slice (first generation) CTs noted limitations in the ability to access a significant number of grafts. This was a result of surgical clips or wires impeding the view, heavy calcification, and motion artifact.
Researchers from France completed a meta-analysis of the peer-reviewed published literature available through 2007. Only those studies which included data in the form of absolute numbers, such as true and false positives and true and false negatives were included. As well, studies that assessed significant obstruction, at least 50 percent lumen reduction, were incorporated.
Studies that were considered included those that incorporated 16- and 64-slice CT. It was speculated that the next generation of CT scanners would reduce the number of grafts that could not be examined. The final cohort assessed included more than 720 patients, the mean age of those was 65 years. The collective patients had more than 2,000 grafts.
The sensitivity of CT in detecting the presence of occlusion or substantial stenosis was 97.6 percent and specificity was marked at 96.7 percent. The positive predictive value was 92.7 percent and the negative predictive value was 98.5 percent.
Benefits of using CT angiography, is that the technique is less expensive. It is additionally less invasive than traditional coronary angiography. The traditional approach requires more contrast, takes longer to complete, and has a higher rate of complications.
June 9, 2008 Related topics: Imaging, Diagnostic, Radiology, Cardiology