STS: CT Angiography Promising but Not Ready to Supplant Catheter Cousin

January 31, 2007

SAN DIEGO -- Although computed tomography angiography showed striking results in a small study reported here among patients with known heart disease, the decision to proceed with a coronary bypass still seems to need a visit by a catheter.

SAN DIEGO, Jan. 31 -- Although computed tomography angiography showed striking results in a small study reported here among patients with known heart disease, the decision to proceed with a coronary bypass still seems to need a visit by a catheter.

Among 25 patients with coronary disease previously diagnosed by traditional angiography, 64-slice CT angiography had a nearly 100% sensitivity and specificity, said Harinder S. Bedi, M.D., of Ludhiana Mediciti in Ludhiana, India, and colleagues. Their findings were presented at the Society of Thoracic Surgeons' meeting here.

But Joseph F. Sabik, III, M.D., of the Cleveland Clinic, who was a discussant in the session, protested that CT angiography is far from becoming a sole basis for bypass surgery.

"These findings and conclusions are in contrast with recent cardiology reports which have reported only 81% sensitivity," he said. "That is not good enough in my mind, and I know in the mind of many, to go ahead and base (decisions on) elective coronary artery bypass surgery."

Verification bias inherent in the study design yielded "extremely and artificially high" sensitivity that does not reflect how the test would perform in patients without known disease, Dr. Sabik said.