Objectives: Although fluoroscopically guided interventional procedures (FGIP) have provided major advances in the treatment of various common diseases, radiation exposures associated with these procedures may cause adverse health effects in workers. We assess risk of circulatory disease incidence and mortality in medical radiation workers performing FGIP. Methods: A US nationwide prospective cohort study of 90 957 radiologic technologists who completed a cohort survey during 1994-1998 was followed until completion of a subsequent survey during 2003-2005 for circulatory disease incidence, or until 31 December 2008 for mortality. Incidence analyses were restricted to the 63 482 technologists who completed both the second survey (1994-1998) and the third survey (2003-2005). Cox proportional hazards models were used to assess adjusted HR and 95% CIs for mortality from all causes, all circulatory diseases, all heart diseases, ischaemic heart disease, stroke, acute myocardial infarction and hypertension in participants who reported ever performing FGIP compared to technologists who never performed FGIP procedures. Adjusted HRs were calculated for self-reported hypertension, stroke and myocardial infarction. Results: We observed a 34% increase in stroke incidence (HR=1.34, 95% CI 1.10 to 1.64) in technologists who performed FGIP compared to those who never performed these procedures. Mortality from stroke was also modestly elevated, although not statistically significant (HR=1.22, 95% CI 0.85 to 1.73). We observed no statistically significant excess risks of incidence or mortality from any other outcome evaluated. Conclusions: Our finding of elevated risk of stroke in workers performing FGIP needs to be confirmed in studies with individual radiation dose data, but nonetheless underlines the need to keep radiation exposure as low as reasonably achievable without compromising key diagnostic information.