The most recent significant development on the FFR front was Dr. Gregg W. Stone’s presentation of the pooled results of the VERDICT and FIRST trials at the Transcatheter Cardiovascular Therapeutics conference in Miami last October. VERDICT and FIRST included 516 patients with 544 intermediate coronary stenoses evaluated by both FFR and IVUS at 24 centers in nine countries. The bottom line was that IVUS-determined minimum luminal cross-sectional area was only modestly correlated with FFR, according to Dr. Stone, professor of medicine and director of cardiovascular research and education at Columbia University Medical Center/New York Presbyterian Hospital.
"I think this clearly showed – and probably conclusively showed – that, while IVUS is useful in many, many settings, it’s probably not the best tool when FFR is available for deciding which lesion is significant and which is not," Dr. Tuzcu said.
"IVUS is a pretty good tool, sometimes, for morphologic assessment. I like it when there’s an issue with the left main coronary artery. I can size the artery, I can understand an ostial lesion, and I can certainly understand better a bifurcation or trifurcation of the left main coronary artery," he added.
The current American College of Cardiology/American Heart Association guidelines give IVUS a class IIa rating as "reasonable" to assess angiographically intermediate stenoses of the left main coronary artery. FFR gets the same relatively tepid IIa rating for assessment of intermediate stenoses in any coronary arteries. In contrast, the latest European Society of Cardiology guidelines on coronary revascularization have bumped up FFR to a class Ia rating, making it the standard for this assessment.
Dr. Tuzcu reported having no financial conflicts.
*CORRECTION, 3/1/2013: In an earlier version of this story, the name of Dr. E. Murat Tuzcu was spelled incorrectly. This version has been updated.