Clinically significant noncardiac findings arise in a tenth of patients undergoing coronary CT angiography (CCTA), according to a substudy of the Scottish CT of the heart (SCOT-HEART) trial published online on 2 January in European Radiology.
Researchers led by Dr. Michelle Williams from the University of Edinburgh in the U.K., identified noncardiac findings in 677 out of the 1,778 patients who underwent CCTA exams for this trial. They classified 173 of these abnormal findings as clinically significant, i.e., causing symptoms or requiring further investigation.
Recommendations for lung nodule follow-up based on the 2005 Fleischner Society guidelines resulted in follow-up imaging for 7.6% of all patients. Application of either of the updated lung nodule guidelines -- the 2015 British Thoracic Society (BTS) or the 2017 Fleischner Society guidelines -- would have decreased the percentage of patients recommended follow-up CT scanning to 2%, Williams and colleagues noted.
Using these newer guidelines would have additionally reduced the cost per patient undergoing CCTA scanning by 50% compared with the 2015 BTS guidelines and 57% with the 2017 Fleischner Society guidelines, without the risk of missing malignancy identified during screening, they said.
"Significant noncardiac findings occur in 10% of patients undergoing CCTA for suspected angina due to coronary heart disease ... usually they represent important incidental findings that require surveillance," the authors wrote.
