Although noncardiac incidental findings are common on cardiac CT (CCT) scans, clinically significant or indeterminate incidental findings are less prevalent; however, investigation of incidental findings is not without cost or risk, according to study results published in the Oct. 13 issue of the Journal of the American College of Cardiology.
Jimmy MacHaalany, MD, from the department of medicine at the University of Ottawa Heart Institute in Ottawa, Ontario, and colleagues sought to determine the incidence, clinical significance and potential financial impact of noncardiac incidental findings identified with CCT.
The researchers evaluated consecutive patients undergoing CCT and their noncardiac structures after full field-of-view (32 to 50 cm) reconstruction. Incidental findings were categorized as clinically significant (CS), indeterminate or clinically insignificant.
Of 966 patients (58 years of age, 55.4 percent men, more than 98 percent outpatients), 41.5 percent of patients had noncardiac incidental findings, the investigators reported. A total of 1.2 percent of patients had CS findings, and 7 percent of the patients had indeterminate findings. At follow-up (18.4 months), none of the indeterminate findings became clinically significant.
Although three patients with indeterminate findings were diagnosed with malignant lesions, they were unrelated to the incidental findings. After adjusting for age, incidental findings were not an independent predictor of noncardiac death, according to the authors. Noncardiac death and cancer death in patients with and without incidental findings were not statistically different. They also reported that one patient suffered a major complication related to the investigation of an incidental finding.
The total direct cost associated with investigating incidental findings was CAD $57,596 ($55,250 U.S.). The authors also determined that the total direct cost of these investigations performed in the United States was $83,035 (U.S.)--taking into account procedure reimbursement differences between the countries.
The researchers wrote that this total did not cover the total economic impact such as the cost of physician follow-up, cost of treatment after diagnosis (e.g., surgery or chemotherapy), societal costs (e.g., lost wages) and patient quality of life.
Overall, the authors concluded that the rates of death were similar in patients with and without incidental findings, and incidental findings were not an independent predictor of noncardiac death.
However, the researchers noted that larger studies are required to assess the potential mortality benefit of identifying incidental findings.