TY - JOUR T1 - Cancer risk related to low-dose ionizing radiation from cardiac imaging in patients after acute myocardial infarction JF - Canadian Medical Association Journal JO - CMAJ SP - 430 LP - 436 DO - 10.1503/cmaj.100463 VL - 183 IS - 4 AU - Mark J. Eisenberg AU - Jonathan Afilalo AU - Patrick R. Lawler AU - Michal Abrahamowicz AU - Hugues Richard AU - Louise Pilote Y1 - 2011/03/08 UR - http://www.cmaj.ca/content/183/4/430.abstract N2 - Background Patients exposed to low-dose ionizing radiation from cardiac imaging and therapeutic procedures after acute myocardial infarction may be at increased risk of cancer. Methods Using an administrative database, we selected a cohort of patients who had an acute myocardial infarction between April 1996 and March 2006 and no history of cancer. We documented all cardiac imaging and therapeutic procedures involving low-dose ionizing radiation. The primary outcome was risk of cancer. Statistical analyses were performed using a time-dependent Cox model adjusted for age, sex and exposure to low-dose ionizing radiation from noncardiac imaging to account for work-up of cancer. Results Of the 82 861 patients included in the cohort, 77% underwent at least one cardiac imaging or therapeutic procedure involving low-dose ionizing radiation in the first year after acute myocardial infarction. The cumulative exposure to radiation from cardiac procedures was 5.3 milliSieverts (mSv) per patient-year, of which 84% occurred during the first year after acute myocardial infarction. A total of 12 020 incident cancers were diagnosed during the follow-up period. There was a dose-dependent relation between exposure to radiation from cardiac procedures and subsequent risk of cancer. For every 10 mSv of low-dose ionizing radiation, there was a 3% increase in the risk of age- and sex-adjusted cancer over a mean follow-up period of five years (hazard ratio 1.003 per milliSievert, 95% confidence interval 1.002–1.004). Interpretation Exposure to low-dose ionizing radiation from cardiac imaging and therapeutic procedures after acute myocardial infarction is associated with an increased risk of cancer. ER -