The researchers said that CT-based estimates of fractional flow reserve ‘could impart considerable discriminatory power to identify and exclude ischemia in patients with suspected CAD’.
Dr Min and his team found that adding estimates of fractional flow reserve improved the accuracy with which CT scans could be used to assess stenosis non-invasively.
Previous studies have suggested that using CT scans alone to study CAD may lead to unnecessary invasive procedures.
This is because CT scans results cannot determine how blood flow is affected by possible vessel blockages.
Dr Min and his team studied 252 patients with suspected or known CAD. They made blinded assessments of haemodynamically significant coronary stenosis using results of CT scans alone, invasive coronary angiography and CT-based estimates of fractional flow reserve.
The researchers found that CT-based estimates of fractional flow reserve identified 90% of cases and were better than estimates using CT alone.
But these estimates also misidentified some patients as having obstructive CAD when they did not.
Dr Min and his team said that, at present, a CT-based estimate of fractional flow reserve may be helpful in excluding ischaemia in patients with CAD.