Is there evidence that coronary CTA is a cost-effective gatekeeper for unnecessary SPECT or catheter angiography?
Berman: Proposed randomized trials comparing SPECT to CT in the diagnostic patient population are currently being evaluated by the National Institutes of Health for potential funding. We hypothesized that there will be cost savings using CT in intermediate-risk patients. But we don’t have the evidence yet and our experience is like Dr. Heller’s. We have an excellent CT service, but it’s underutilized. Ruddy: We have a program that handles about 2000 CTAs annually. We found that our normalcy rate in the cath lab has decreased, which indicates more appropriate use of the cath lab. Clinicians use CTA because its high negative predictive value can effectively rule out the low-probability patients. About one-third of these patients, however, go on to SPECT because CTA reveals a significant stenosis. In terms of numbers, CTA has not adversely affected our SPECT volume, which has increased about 5 percent for each of the past three years.
