OBJECTIVES: 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 milli Sieverts (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).
CONCLUSIONS: Exposure to low-dose ionizing radiation from cardiac imaging and therapeutic procedures after acute myocardial infarction is associated with an increased risk of cancer.
Cardiopulmonary Imaging, Section Head
Cleveland Clinic Florida
Latest posts by Jacobo Kirsch (see all)
- CMR-Based Characterization of Cardiac Amyloidosis - October 15, 2014
- CMR in the Assessment of Cardiac Masses: Primary Malignant Tumors - October 15, 2014
- Infarct Tissue Heterogeneity By Contrast-Enhanced Magnetic Resonance Imaging Is A Novel Predictor of Mortality in Patients With Chronic Coronary Artery Disease and Left Ventricular Dysfunction - October 7, 2014