Patients underwent a median (midpoint) of 15 procedures involving radiation exposure, of which 4 were high-dose procedures, defined as an effective dose of at least 3 mSv (millisievert; a measure of radiation dose), the equivalent of 1 year's natural background radiation. A total of 200 patients (18.2 percent) had at least 3 MPIs and 4.9 percent had at least 5 MPI examinations.
The researchers found that the median cumulative estimated effective dose from MPI alone was 28.9 mSv, and for all medical testing, was 64.0 mSv. A total of 71 patients (6.5 percent) received cumulative doses of more than 100 mSv due to MPI alone, and 31.4 percent of patients received more than 100 mSv from all medical sources, including 120 patients (10.9 percent) who received cumulative dose of more than 200 mSv.
The primary reason for testing was chest pain, breathing difficulty, or both in 66.8 percent of examinations. More than 80 percent of initial and 90 percent of repeat MPI examinations were performed in patients with known cardiac disease or symptoms consistent with it. Of 1,097 patients undergoing index MPI, 38.6 percent underwent additional MPI studies. For this group of patients undergoing multiple MPIs, the median cumulative estimated effective dose was 121 mSv.
Patients undergoing multiple MPI examinations were significantly more likely to be older and male. Men and white patients had higher cumulative estimated effective doses.
"Our study reveals very high cumulative estimated effective doses to many patients undergoing MPI, and especially to patients undergoing repeat MPI testing. More than 30 percent of patients received a cumulative estimated effective dose of more than 100 mSv, a level at which there is little controversy over the potential for increased cancer risks," the authors write. "Efforts are n
|Contact: Alex Lyda|
JAMA and Archives Journals